Interesting! When I was in high school (1977), I rode a 1973 Suzuki GT250 two-stroke street bike. People now would laugh at a 250 motorcycle, but it was a lot of fun to ride. It had a "Ram Air" air scoop above the cylinder head, and it had a separate tank that I poured oil into. It had a glass sight window to let me know when to add more oil. The oil was automatically mixed with the gasoline in the right proportion. I miss that bike. I miss the girl who used to sit behind me. Her helmet would bump against mine each time I shifted gears.
People today don't know about the days when a bike 250-350cc was considered a touring bike. It was 1969 before Honda even produced a 750. Before that, people were touring the country on 350's and later the 450's. I had a 1965 CB150 with a two-cylinder, four-stroke "Bentley touring engine."
A slow bike ridden fast is where the fun is lol Honestly, spending time in the middle east where there are thousands of little 125's and 250's made me fall in love with the little bikes. My ride when I'm home is a 53 Harley Hummer with a lil two stroke 165cc. Got it from an old salt down the road for an absolute steal. He knew what he had but wanted it to go where it would be ridden.
Two Strokes 4 EVER! My first machine was a 73 Yamaha 80. I Was HOOKED! Ahhh that Smell! That Sound! Gerritsen Beach Bklyn! Scrambling in the morning! All day Long & that seawater smell mixed with those Engines! Intoxicating! The the Elsinore! BEST Decade of my life! On Any Sunday! Those Husqvarna 400 Cross! Unreal! Best Times Ever! Fond Memories Sorely MISSED! God Bless...😊😊
And the rd350 will remain my favorite 2 wheeled vehicle of all time, can't wait to find a new one in good condition near where I live so I can blow a check on it lol
As a dirt bike AND snowmobile guy. I feel it’s important to point out that the winter guys have been doing crankcase and transfer port EFI since the early 2000’s. And more recently direct injection two strokes for more than a decade. Both BRP and Polaris have recently introduced turbocharged EFI 2 strokes making around 200hp per litre. There is a lot of potential in two stroke fuel injection. Hopefully other manufacturers catch on to the demand.
@@victorvannatter312 It's very expensive, complex & heavy, complete opposites to why manufacturers love 2 strokes for (cheap, simple & light very important on motorcycles), and it involves a lot of engineering by each manufacturer to make sure they don't get slapped with patent lawsuits, plus even 4 strokes are now having trouble passing modern emission norms & EVs taking over, it's extremely difficult for a 2 stroke engine that burns oil, to pass.
My 01 cr250 Honda is the fastest machine on the planet beat NASA and all them people with it 1000s of hp way more American and reliable than Harley garbage and 4jokes if it don't smoke it's a joke
A great video covering my motorcycle youth. Two strokes were a blast. I wisely kept my last two stroke, a Yamaha RZ350. I still have it, still ride it frequently. I will never sell it. Having too much fun every time I ride it.
The main problem with owning a two stroke is that they are not very fault tolerant. If something's wrong then they tend not to run at all where a four stroke will run rough - which tends to be easier to trouble-shoot. When I was at college, a friend and I tuned up an MZ 150. In stock form it did 60 mph and 60 mpg (UK gallons). When we finished with it, it did 80 mph and 80 mpg (with a very sharp power band). Happy days.😄
Bart, you have some of the very best videos. I grew up in the golden age of two strokes, My rides included Kawasaki, Suzuki, Yamaha, Bultaco and Ossa. I now ride a four stroke under protest.
@@waynez1025 I rode a Bultaco with a bored out cylinder. I think it was originally a 350 but it was as you say a monster. Incredible acceleration up to a speed I never attained. I was scared of getting busted
Ossa had this sublimely beautiful 500cc twin that i`ve only seen pictures of in the `70s! Apparently it was never really fully developed but she was a JawDropper! If Only !
My grandfather was back in the day one of germanys best Trialriders, once on a raceday a friend of him crashed with his DKW (he was a factory rider) and unfortunately damaged his exhaust, because it was a little sport and money was rare he had no other exhaust to change. But he got extremly lucky because the dent helped the engine to gain 2hp more, so he won the race. Stund by this happening DKW tried to replicate the dent for all there Motorcycles, but it never worked out on a cheap basis because the dent was far to complex to machine for the time
I love 2-stroke street bikes! I have owned several. The last one was a 1984 Yamaha RZ350. This was the last street-legal 2-stroke road bike sold in the USA. It even had catalytic converters as a last-ditch attempt to pass EPA regulations. I promptly ditched the catalytic converters and replaced them with Toomey expansion chambers. It cut 30 pounds and added about 30% more power. Sadly, I sold it about 20 years ago. I would love to have a modern high-power 2-stroke street bike.
I bought a RZ350 in 84 after growing up riding RD350's and a RD400, it was the best two-stroke street bike ever made. Now I live in Cedartown, GA. where KTM has a bike park called Highland Park/KTM World. You can rent a bike for the day and they have the motocross track and a bunch of cool trails, you can still get your two-stroke fix if you want.
@@MrCrispyNips04 Yes, the US had the equivalent of somewhere around EURO 3 emission regulations by the mid 1980's. As far as I know, all the 2-strokes now available are off-road only. Some States, like California, have even stricter air emission regs for offroad-only motorcycles on public land. For a long time the US had stricter motor vehicle emission standards than the EU, but that changed with Euro 4 and 5.
I've got a 2001 Honda Elite SR. I'm not sure if you'd consider that a street bike, but it was still legally sold in the US for on road use and it is a two stroke. Yamaha also sold the two stroke Vino until the early 2000s
@@middlesiderrider A lot of Ststes exempted 2-strokes under a certain displacement. Often, 50cc was the limit. Some mopeds and scooters were exempted as well. In NC anything under 50cc did not require a license, as well. I recall a friend who had his license suspended buying a 50cc moped and installing a 100cc "big bore kit", hoping that no police would notice. They didn't.
Veteran 2-stroke maniac here. I started at 15 years old, with a Puch Grand Prix, which used to do 65 mph. Then progressed to a Suzuki X5 200. I also owned a BSA Bantam 175, then my all time favourite a 1974 Suzuki GT 750, which I bought in 1982 and sold in 2003. I had a knack for finding that extra 5 or 10 mph out of a 2-stroke, all my mates used to bring their bikes to me for a tune and tinker, to get every ounce of power from the bikes potential, playing with the jetting, exhaust ports, different spark plugs, different exhaust pipes, etc. Happy days!
@@bartmotorcycle The Rotax ETEC direct injection voice coil two stroke engine is alive and well in the snowmobile world. Skidoo has been using this engine to power their snowmobiles for more than a decade. There's even a turbo-charged version for high altitudes. Welcome to the 21st Century!
@@bartmotorcycleBart, I appreciate you at least mentioned MZ but how can you skip, even in passing, the legendary Jawa and CZ? Especially CZ as a dirt bike.... Sad.... BTW, I have a 1970 Jawa with a Velorex sidecar
@@bartmotorcycle People Must get Educated, that the Global Warming Is Absolutely Not connected with the Global Pollution !!! ! !!! These Are Two Entirely Separated Processes !!! ! !!! Just as the Global weather catastrophes Are Absolutely Not connected with the Global Warming. Peace with you.
I ride 2 and 4 stroke machines, but I have to say the 2 strokes are more fun. I love the violent power delivery--nothing beats a 2 strokes when you're on the pipe. I also love the smell and the sound. They can be more challenging to ride fast because the narrower powerband, but that's also part of the fun.
to bad you dont know any thing at all of how or why a two stoke operates and you dont have a clue of what you are trying to explain what it is being on the pipe or in the power band
I had a 1976 Suzuki 750 CC "Water Buffalo". Great bike, was trouble free. I got teased a lot by friends who rode big Kawasaki or Honda 4 cylinder bikes, but held my own with any of them.
They were very good. I worked as a mechanic/service manager for a dealer upstate from NYC and we sold a few of them. They were prone to puddle lubricating oils in the mufflers and I had one actually catch fire in the mufflers on an extended road test where I could run the bike hard for a few minutes. I think the smoking and associated inconveniences went a long way to causing them to lose appeal. The new GS four strokes were more civilized in most ways and customers responded to that as a positive against the two-strokes.
@@danielklopp7007 I put expansion chambers on mine as well, but did not rejet it, so I had to watch it, or I'd run it too lean racing. It would pull huge wheelies with those tuned pipes.
From the Mount Rushmore of Rocket League, to becoming a top tier motorcycle historian. Proud of you, my guy. Your passion for bikes oozes through these vids.
3:15 Expansion chambers don't force "exhaust back into the cylinder". The port timing is such that fuel/air mixture is allowed to pass through the cylinder & into the exhaust tract. Then the inlet port closes & the resonance in the expansion chamber pushes the fuel/air mixture back into the cylinder. The exhaust port then gets closed off. It's a kind of supercharger with no moving parts.
@@peterbradburn9115 I suspect that a lot of the knowledge gained from Germany's WWII pulse jets is indeed what led to the expansion chamber. They used pulse jets on the V1 "buzz bombs" and were trying to use them for manned aircraft as well.
@@retiredbore378 The development of the exhaust "power valve" allowed the dimension of the exhaust port to change, improving efficiency and reducing emissions somewhat.
I always understood the function of the expansion chambers as being able to "pull", by means of resonance and exhaust gas flow, more fresh fuel/air mixture into the cylinders. Kind of how the condenser of a steam turbine creates a vacuum.
@spaceflight1019 My understanding is that when the engine is "on the pipe" as we used to say, the exhaust pulse is reflected back up the pipe to both block the fuel-air mixture from exiting the cylinder and providing a suction like effect when the exhaust port is opened to help scavenge the burned gasses. Needless to say timing is critical and that is why the rpm power band is narrow or limited. A 2 stroke capable of revving to 10K rpms my only produce high power over 2K of rpms.
Brilliant brilliant video. You covered the issues so well. As the owner of an RG500 street bike it was music to my ears. I've always preferred 2 strokes to four. Probably because I've not typically had bikes to just go from point a to point b but rather for the fun only a 2 stroke can give. Btw the RC211V was a V5
Well Mr. Bart I have been riding and racing “them there “motorcycles I would guess 2 times longer than you have been alive. I am here to say you do a wonderful job making your videos . Thank you.
This video brought back so many memories! All of my early bikes were Suzuki 2 strokes - started off at 16 years old on a metallic red 1977 AP50, then went on to a GT125 twin, GT 350 Rebel, and GT380. Virtually all my peers also rode either Suzukis Yamahas or Kawasaki 2 strokes Still remember the evocative sound and smell of a multi cylinder 2 stroke on fast choke idle first thing on a chilly morning... Good times
Nothing will ever beat the sound of a two stroke triple running on his expansion pipes. And a 3-1 pipe, with a huge middle channel, might not be the best for power, but the sound.....
My first vehicle was a 79 Yamaha DT250. Loved that thing. Rode it all over the Black Hills trails and back and forth to school. Not exactly a speedster. Top speed of 55 if I remember. Obnoxiously loud. And hella fun. Good memories.
My first vehicle at age 15 was a '79 DT125 with 20k miles when I got it. It topped at about 55mph...until I cleaned out the carbon in the baffle and a few other things like new rings....then it almost could do 80!
jf he is a motorcycle historian he is telling a tale that apparently he has invented on his own that never happened in order to gain subscribers that equals money for telling you anything he wants weather it happened the way he said or not ! the thing is i am older than dirt and have lived through all of his spoken history so i can tell instantly if what is said today happened or not simply because i was there and most all of you were not
I owned a 500 H1. I'm sorry I ever sold it. Out of all the bikes I've owned, it was my favorite. Handled like crap, but fast in a straight line. Great bike.
RD350 that’s all ya gotta say. Thanks for sharing about the Resonance effect. That was the height of the development. A neighbor had one around 1980 and never forget the start up, plus it was light and maneuverable! I started with a Yamaha 80 in the SoCal deserts. My cousins raced 250s.
Interesting video! One thing you didn't mention was the Suzuki GT (380,550 &750) series which were effectively grand tourer 2 stroke triples. They were tamer than Kawasaki triples but the GT750 is one of the most sophisticated 2 stroke bikes for its time and potentially ever made which is why it is officially one of the 240 Landmark of Japanese Automotive Engineering.
I had a couple of the 380s and a 550 back in the 1980's. My friend had the 250, which was a twin instead of a triple. I never did get to try the 750 model.
I had the GT380. A most civilised and long-legged machine. A police car totalled it, and nearly me as well but the payout bought me my first Goldwing. Now I wish I had the GT back...ah well.
@@chrispomphrett4283 I was a dirt bike kid so I was surprised that a two stroke was built to be a touring machine. My father GAVE AWAY my last 380 when I joined the Army in 91. He apologized later by giving me the money for a HD chopper though.
Know the feeling! I had an S2 350. Getting it started on 2 cylinders first...and then blipping the throttle so the centre one would kick in. Becoming expert on setting the points with a cigarette paper and transistor radio interference. Would match an R5 but not an RD. Kwackers still looked the best though..
My first bike was/is (I still have it, several bikes later) a barn-find 85 Suzuki AX 100R. It has no battery, makes a pittance for power, and is about the fourth most fun bike I've ever ridden. It's a riot - loud, smoky, accelerates like a stabbed rat and has a ridiculous powerband where nothing happens for most of the rev range, before ALL the torque and power kicks in. It weighs 78kg, and even though its got a slow top speed, it's great fun. I'll never get rid of it.
This is an extremely good story. I myself have been a 50cc racer for 10 years in the 70's and early 80's. I've enjoyed it. You also brought in Kaaden very thoughtfully because he was the man.
Couldn't agree more.. :) My younger brother had several Kawasaki 500's , widow makers. I had several Suzuki T500's. The Kawasaki was mental, the Suzuki not as much but handling was light years ahead.
Having started out on 70s Suzuki GTs, I've always been sad about their disappearance - this was a good essay, thanks! How about a deep dive into some of the specific technologies that drove 2T engines forward as innovations? Eg - power valves, reed valve inlets, resonant exhausts (expansion boxes), water cooling - that would be *very* interesting for an old greybeard like me 🙂
The 70's four-stroke GT's motors had a unique clattering sound. You could always tell it was a Suzuki coming without looking. I asked a mechanic/builder friend (whose work was in the magazines of the day) what was up with that sound. He told me that Suzuki used "extremely thin piston rings."
I love the fact that when you showed the top muscle bikes from the magazines at the 5:20 segment, I owned 2 of those motorcycle's, almost, In 1977, I had a Kawasaki KZ1000 but when the Suzuki GS1000 E came out the next year, I traded in the Kawi for the GS, just so I could say I'm driving the fastest motorcycle in the world for 2 years in a row. I worked a lot of shifts pumping gas for 2 years so that I could buy that Kawi at the age of 18.
One of my biggest regrets it selling my RZ 350 with a Toomey set up. Awesome video, the attack with handicaps blows, didn't realize it killed both gp and dirt.
Bart made a good point when he stated that the race organizations and motorcycle manufacturers wanted the race bikes to be closer to what was being sold to consumers. Things may change if several manufacturers are able to develop 2-strokes that meet various emission regulations. Formula 1 in auto racing took another tack and their engines are supposedly the future of street technology (hybrids with energy recovery and reduced fuel consumption).
In the sixties, Bridgestone made motorcycles. One bike in particular was the Bridgestone 350 GTR. It was more expensive than the other Japanese offerings but it was a fantastic motorcycle. It used nickelsil in the cylinder liner and was overall very high quality. I suspect Bridgestone quit making motorcycles because they saw what was coming down the pike regarding emissions and rather than focusing R&D on development of a four stroke Powerplant, decided to just stick to producing tires.
I think the bore was chromed. Nikasil came to use later. I also remember reading that the other Japanese motorcycle manufacturers threatened to stop buying Bridgestone tires unless Bridgestone exited the motorcycle market.
My understanding was the big four declared: "If you want us to keep buying your tyres for our motorcycles, stop making the latter". Bridgestone made a lot more money from its tyre making than motorcycles so it made good fiscal sense.
My elder brother had a 1976 Jawa 250 two stroke motorcycle. He had painted it in red color by himself and used to tune it. I still remember the sound and look of it sometimes.
Your consistancy amazes me, all the stuff you've posted is high quality; BTW I love the old b&w archive pics and film. People may have been even more goofy back then than they are today. Makes me feel right at home.
My first bike was a used, 70-something Suzuki GT-250. Man, that bike was a blast to drive and it was bulletproof reliable. Great sound and fast revving. Wish I could have kept it.
Man, I’ve been advocating for 2T engines for my whole life, and I’ve been really pissed ever since they wiped them out because…well, hype. This video gives me HOPE, for I assume you’re a young guy who actually appreciates what’s behind riding and competition. I owned 2S in my youth and 4S in my not so youth and man, what I’d give to have that scream and oil smell from 2S back in the streets again. Thx for this. Keep it going!
Great video, thanks. I have been a biker for nearly 50 years. I loved my Triumph twin and I loved my Honda four. For lightweight fun, whether scratching twisty back roads or commuting, I still love my MZ 250 (the only bike I currently own, although I have the occasional use of a Yamaha 1300). Emissions regulations targeted the two stroke engine by focusing on unburnt hydrocarbons. Interestingly, the traditional two stroke does rather better than it's four stroke brethren on oxides of nitrogen...
I think it's sad that you never mention Kreidler when talking about 2-strokes. The Kreidler Florett bikes were fast, comfortable, extremely reliable and so insanely beautiful. Legend says that the reason they went bankrupt was a lack in sales of spare parts. Anyways good video as always.
I remember my older brother telling me about a friend of his who, after having exclusively British bikes bought a Honda CD175 (4-stroke twin) brand new. He complained that it was smoky and kept breaking down, and blamed this on 'low quality Jap crap'. Then I got to the truth - turned out he was told 'All Japanese bikes are 2-strokes.' Where he got this from who knows? So I realised he was putting oil in the tank with the fuel (all 2-strokes at the time were pre-mix). Which neatly explains the smoking and the unreliability...
Two stokes are awesome, I remember when they rev out as you run out of fuel, as you frantically try to switch to reserve, and of course the powerbands, nothing compares
bruh this just literally happened to me today. I have a Kawasaki HD3 125 cc two stroke motorcycle and I forgot that I've set the petcock to main instead of reserve. As I was cruising down the road, it immediately revved so high that I thought it would blow out. Just knew it through this comment that two stroke engine do that!
Nice video as Always! I would like to add a small correction at 10:55, the RC211V was a V5 engine not a V4, this V5 engine was an amazing piece of engeneering and was very dominant in MotoGP, with Vale the bike was unstoppable, but the Doctor managed to win against this beast in 2004 and 2005 when he was riding for Yamaha, then after Nicky Hayden became a MotoGp champion for Honda in 2006 the regulations changed and no 5 cyl engines were allowed.
Great video I was a bike mechanic back in the 70s built A lot of RD 400. And Had several Kawasaki triples. I still remember doing wheelie's past AZ1R. On my RD4 hundreds. In the quarter mile
Growing up me and my fellow degenerate teenage friends rode around town on our scooters, souping them up, crashing constantly, off-roading, and swapping parts when we bent the forks in or found a bigger front tire, etc. my buddy had the only one with a two-stroke and it was so mysterious and incomprehensible to me, foreign almost but kind of awesome
I owned a 50cc scooter and I gotta say that thing made me hate two strokes. Slightly clogged jets in the carb? Piston gets fried. Failing oil pump? Piston gets fried. Going top speed for a bit too long? Piston gets fried. And man how moody it was to start depending on the temperature was annoying
youre talking 50 yrs ago! get a Kawasaki 150cc proper modern 2 stroke single cylinder liquid cooled little rascal bike today and see the difference!...
@@fidelcatsro6948 i bet water cooling and fuel injection makes all the difference. The scooter wasnt even that old. It was from 2006. Theyre just poor build quality. Everytime I see that model standing around somewhere I always find the same puddle of oil I had under mine
My first motorcycle was a used Yamaha RD200. It was a nice little motorcycle, though the clutch died after one summer of hard driving in rush hour traffic. Never had a two-stroke after that, but it was a nifty little street bike.
It is important to keep the performance of 1960's and 1970's motorcycles into perspective. I liked the Yamaha RD350 and RD400 two-strokes. They were considered fairly high performance at the time. but if you look at the acceleration and quarter mile times, they were slower than the current Kawasaki Z400/Ninja 400.
@@darinhampel4149 Yes, some places outside the US got the next couple of generations of two-strokes with "power valves" and by all accounts, they were a lot of fun. Yamaha did not do a lot of exhaust tuning to their 2-strokes for the street. I suspect that it was to spread the torque over a wider area. I have read that the RD350's and RD400's were very different with tuned expansion chambers. They had a lot more power but most of that was in a narrow RPM band, making them difficult to use in traffic.
Oh, but that's not true. It's not the CO2 that is causing the smog, it's the uncombusted fuel that is ejected, the lubrication is being burned off, up to 170x more hydrocarbons, 10-20x more carbon monoxide, up to 8x more nitrogen oxide, and more particulate pollution. These things are what cause smog, and all those 2-strokes were a major contributor. Remember, you said it yourself - a restrictive exhaust on a 2 stroke, such as a catalytic converter which removes a lot of the pollutants, reduces the only reason anybody would ever run a 2 stroke, greater power for the displacement.
There have been direct injection two stroke outboard engines from both Mercury Marine's "Optimax" series and Yamaha's HPDI (high pressure direct injection) series, as well Evinrude's "ETEC" series, for over the last 20 years... Direct injection is not "impossible" with 2 strokes as you said, and is very common in 2 stroke outboard marine engines, and only now in the last few years have they been getting phased out due to CARB standards, though many still remain...
True. It did tend to clog up the exhausts on road bikes with separate 2 stroke lube tanks. Possibley due to its veggie origins rather than the mínealaíon for whoch they were designed. We took to daubing a little daily on the exhaust tip to keep some remanant of the smell. Then Esso (Exxon) a bit player in 2T lube came out with a mineral oil that smelled almost like the real R. .......
I always found Jawas fascinating due to being so different from popular Japanese bikes (USA). Every report I've seen on the 350 had about 21 horsepower and the speed/acceleration numbers reflected that. I would love to hear more about any version boosted to 34HP.
I just discovered your channel and have really been enjoying the content! There is a LOT of motorcycle-related stuff on RUclips as we all know, but not a lot of motorcycle history. I can pick any one of your videos and at least 90% of the information will be new to me. You're filling a niche and doing a great job of it-keep it up!
I remember my old RD-350 back in '73... lightweight and so much acceleration it would backflip you on takeoff if you weren't careful. Even the new monster Kawasaki Z1 knew not to bet against the RD when coming off the starting line. If I remember correctly the RD had 46hp; for comparison the popular Honda CB350 had 25hp. For a motorcycle the two-stroke RD got really crappy gas mileage even if ya babied it.
excellent video, i grew up in the 70s on two strokes and its such a shame that kids will never experience the feeling of a time when ALL dirt bikes were 2stroke, theres nothing like the sound of a 2 stroke hitting its powerband!
The simplicity of two strokes is so beautiful. Improving the emissions is such a major advancement, because they did it while simultaneously improving the torque curve and widening the power band. Simply amazing. I agree, there is a real future for two-strokes again. Even if they continue to only be used in enduro, maybe motocross again, and scooters, the improvement of pollution in asian cities (and thereby all air) by scooters being upgraded to modern EFI 2T would be significant. Also, the production carbon footprint of 2Ts should be drastically lower compared to the 4Ts, which require so many more parts and production steps/time. I even wonder if tiny two-strokes could be used as on-board generators to recharge a battery in an EV on the fly, for an insignificant emissions hit, to keep from having to stop for slow charges or swap batteries. Might be a worthwhile trade-off, allowing for a place for fossil fuels used very efficiently and reducing demand on coal-burning grids, while solving the range and recharge time problems.
I've had two stoke motorbikes in the 70 s' and there is nothing like them. For me a 1970s' Japanese two stoke motorcycle is unbeatable - bring them back!
I personally cant stomach 2-strokes, because I associate them with mopeds, just because of the sound and the smell. 4 stroke sounds so much more powerful and grown up, but yeah that is me that. Honda mt5, yamaha dt50, banzai :D
Take the suter 500 mmx 2 stroke inline 4 576cc engine. Makes more power and weighs lighter than the new kawasaki H2R and that's a 4 stroke 999cc inline 4 motor. Tell me who's more grown up now ignoramus degenerate?
You weren't riding the right machines then. When I hear and smell two stroke I think of power. I've ridden some absolutely rowdy two stroke motorcycles and snowmobiles. Nothing like a good two stroke!
@@Friscorockhead does not really matter if I have ridden the right machines or not, if I as an 15 year old teen rides mopeds then ofcourse I will associate 2-strokes with mopeds ie bikes for children. I have ridden 125 and 250 2 strokes "gp bikes" and still every time I put my legs over such a bike I still get reminded of 2 strokes being mopeds. Nothing to do with them having power or not. That is my nostalgia.
I grew up riding 2-strokes; dirt and road bikes that were absolute pocket monsters. In the late 80s, I had the privilege of owning a Husqvarna WR400, and a works Yamaha RD350LC. With their utterly vicious power band, I was completely gob smacked every time I rode these bikes. Once they hit the sweet spot on the pipes, it was like the old THX sound demo where the individual notes are jumbled and disorganized until they all come together to make the perfect power chord and all hell breaks loose. 4-strokes make ridiculous power these days, but 2-strokes are an addiction.
~9:50, on handicapping. I moved from the Midwest to NYState in the early '60s and ran into this peculiar thing: The racing class I was involved with there pitted 200cc four strokes against 250cc two strokes, just backwards from what's covered here. I rode a 200cc Parilla Wildcat against 250cc Greeves, CZs, which were the most common two-stroke competition scrambler bikes at the time and wasn't beaten by any two stroke bikes. Within a year, the classes were restructured and with that, I began to compete on a 250cc Bultaco. At that time, they separated the classes by engine type so I could still race the Parilla but only against other four-strokes up to 250cc (and it was still competitive). The two-stoke scrambles and motocross classes took off with rapid improvements in the machines.
Do you remember roughly when the 2-strokes began to improve dramatically? I don't recall when I started seeing expansion chambers on them and recall that even mid 1970's two-stroke street and "enduro" (dual sport) bikes tended not to have them. I suspect that it was to keep the wide torque band. The highly-tuned 2-strokes tended to be nearly unrideable since most of the power was in a narrow RPM band. The introduction of the "power valve" in the 1980's helped greatly.
@@jfess1911 I suppose it depended some on one's location. For me, in Kansas at the time, it was the arrival of Bultaco machines in 1961. They had full expansion chambers (Sherpa S models) and put out serious horsepower. Two friends of mine were trying to start a dealership but didn't have the resources to build it up to be a good competition shop. I took over the purchase of a 175cc model when the original buyer failed. It was competitive with most 250s but developed issues and I sold if off as I was relocating to the NYC area in a month or so. High performing two-strokes were rapidly gaining use in the West, that was '63. Within a year I was sponsored on the Parilla but the owner was planning on importing Husqvarna and had one of the early issues which was a very promising machine. Twin pipe CZs were showing up regularly as well as improved Maicos at about the same time on the East Coast and the power battles really began when the Bultaco Metisse 250s started showing up in '65. It took a good deal of experimenting to tune expansion chambers on street bikes and we never got involved with promoting it. We occasionally took in bikes that the owners had attempted their own tuning. We didn't have the facilities or number of personnel to take on ambitious projects. We dealt mostly with good service for new machines. It's worth mentioning what it took on those early machines to make them fit for their purpose. Bultacos had to be lubricated with Castrol R 40 which was mixed with acetone so it would blend with gasoline. Also, the stresses were popping up weaknesses and our one 200cc Sherpa S lost its wrist pin bushing starting the second season, they didn't yet use needle bearings in the con-rod top end. There was a break in process that included pulling the head, cylinder and piston, and sanding any shiny piston scuff spots to ward of seizures.
@@whalesong999 Thanks. I didn't start paying attention to motorcycles until the 1970's and was aware that various race machines had expansion chambers but many other 2-stroke motorcycles did not. I rode a Yamaha AG175 farm bike from the early 1980's and it still didn't have an expansion chamber, for goodness sake.
@@jfess1911 Utility bikes really did well with muffler systems that were developed concurrently with improvements in the engines themselves. I had a Bultaco Matador, and enduro bike, that had a rather simple muffler system but still had plenty of oomph to successfully compete with outright race machines if ridden well. Later on, I rode a 230cc OSSA Pioneer and it also had a very good muffler/expansion chamber. When I first took an interest in racing, some riders were simply removing the entire mufflers and just letting the header pipe exit with no restrictions. The performance actually worsened, only the removal of the weight had meant any advantage.
@@whalesong999 The Yamaha AG series was designed for agricultural use rather than the street. It pulled well at low revs and reportedly had only 13.7hp according to a Yamaha advertisement. My understanding is that it used the older CT3 engine and though a 1983 model, still had dual shocks. It was asssigned to me when I worked in Marrakech Morocco, so it was often used in 100+°F (38+°C). I never seized mine, but others did since they largely ran them full throttle to keep up with traffic.
Some random thoughts: Imagine an expansion chamber exhaust system on a Scott? If only... Stock exhaust system or expansion chamber system- none sounded good to the average person... Doesn't hurt anything? Only one commenter here mentioned (S.E. Asian countries) pollution. You have to experience the pollution in the major cities of Thailand, India, China, Philippines etc. where 2 stroke motorcycles are sold... Can anyone settle a 50+ year old bet about a Bridgestone motorcycle hand throttle? One said the twist throttle worked conventionally, the other said counter-conventionally... Great video young man!...
Mythbusters tackled the myth of motorcycles polluting less than cars in s09e13. The verdict was that motorcycles polluted more simply because there's less room to add components and units to eliminate the emissions on a bike than a car.
this reminds me of may dad's stories about hillclimb racing in his dune buggy. there were two racing classes: the kids who could afford "paddlewheel" tires, and the poorer kids who would weld two wheels together and spread one tire over two inner tubes to get a wider contact patch. there wa sone weekend he was the only one who showed up without paddlewheels, so they talked him into racing in the paddlewheel class, and he said he would never make that mistake again. similarly, requiring four stroke and two stroke to have matching displacement does give the two stroke a significant advantage. matching them by airflow or fuel flow would make for a closer race.
Back in the 80's I owned several of the Suzuki GT series two stroke street bikes. I had a couple 380 models (they kept blowing up the middle piston) and a 550. My friend had the 250 version which was a twin. The '76 model had a digital gear indicator which must have been fancy in the 70's. I took one of the 380's and put on drag bars, made rear-sets in shop class, and found a 3 into 1 exhaust at a junk yard. It was still pretty slow. Sounded like a popcorn popper at idle. Smoked like a chimney at high RPM but was fairly smooth at reasonable RPM. Then I got to ride a full race RZ350 a friend owned and man was that thing a blast. Basically a Banshee motor in a sport bike.
In the beginning of my riding I rode the old four stroke scramblers. When the two stroke motocrossers hit our shores I moved over. I basically rode nothing but two strokes from the 70’s-90’, But I was riding off road as a racer. When I changed to the street is when I moved to the big four cylinder four stroke machines. I love them both, just depends on the application your looking for. Some applications need more smooth torque, others more instantaneous hp.
i regretted the loss of 2-strokes, light and simple were powerful attraction. but they smoked. sigh. relax, people, the future is electrical. no smoke. great torque. you'll get used to the silence.
I started with a 72 Suzuki GT380 back in 1977. Previous owner had ripped it apart to fix a points problem and had a garage fire where several major parts were destroyed. Got for a song and rebuilt it. Started on the first kick (may have been the second kick) and as described by another, took off like a stabbed rat. Rumoured it could out drag a Porsche 911. Had to sell it when posted in Germany. Insert tear here. Current bike is 93 CBR600F2 (AKA GOOF2) and also moves but I still remember rides with buddies (one had a GT500). Thanks for the article. I'll look for others.
It is cool that you love your bikes. I have had riding buddies that also loved 2 strokes. I've ridden them and for whatever reason it was not my cup of tea. I did not find powerband helpful but I do see it is thrilling. I preferred the 4 strokes for the more predictable power delivery. Really cool video!
My Dad and I are trying to restore his '73 Yamaha AT3 to rideable condition. Because old-school 2-Stroke awesomeness. We call it "The Landlocked Jet-Ski" because of the noise of the power pipe. Been a lot of work already and finding a gas tank that wasn't rusted out or dented to pot was a royal PITA, but we're (slowly) getting there! Wish us luck
Great video. I had a 1971 Suzuki T-500 two stroke. It had a wide torque curve. It used transmission oil like a 4 stroke. I remember riding it through Riverside, CA (just east of Los Angeles). My eyes were burning and tearing up and it was hard to breath. California has already planned the end of all internal combustion engines. Well, everything has advantages and disadvantages.
Yeah, and we have rolling blackouts because the electrical grid isn't strong enough. How are they going to charge these damn things? Maybe hydrogen motorcycles?
You mentioned the one weakness of Suzuki twins, using transmission oil. Not all came to that but it began with the 250cc T20 "Hustler" and since they all were developed with that basic architecture, the weakness followed. It was a good idea, having transmission oil to lube the crankshaft main bearing on the drive end (the T20 had that feature for their center mains as well) but the quality of the seals is what caused the deterioration leading slurping up some of the transmission oil. IIRC, we had a time where Dexron automatic transmission oil was specified and that was a good solution because it helped the service life of the seals.
Interesting! When I was in high school (1977), I rode a 1973 Suzuki GT250 two-stroke street bike. People now would laugh at a 250 motorcycle, but it was a lot of fun to ride. It had a "Ram Air" air scoop above the cylinder head, and it had a separate tank that I poured oil into. It had a glass sight window to let me know when to add more oil. The oil was automatically mixed with the gasoline in the right proportion. I miss that bike. I miss the girl who used to sit behind me. Her helmet would bump against mine each time I shifted gears.
People today don't know about the days when a bike 250-350cc was considered a touring bike. It was 1969 before Honda even produced a 750. Before that, people were touring the country on 350's and later the 450's. I had a 1965 CB150 with a two-cylinder, four-stroke "Bentley touring engine."
I had one too. It was actually a Benly Touring, much different and less cool than the Hawk and Super Hawk models. Still, so much fun for kids like us…
A slow bike ridden fast is where the fun is lol
Honestly, spending time in the middle east where there are thousands of little 125's and 250's made me fall in love with the little bikes. My ride when I'm home is a 53 Harley Hummer with a lil two stroke 165cc. Got it from an old salt down the road for an absolute steal. He knew what he had but wanted it to go where it would be ridden.
I got a 77 Suzuki gt185 thing is a true blast on track… as a younger guy really wish they still made bikes like these
Two Strokes 4 EVER! My first machine was a 73 Yamaha 80. I Was HOOKED! Ahhh that Smell! That Sound! Gerritsen Beach Bklyn! Scrambling in the morning! All day Long & that seawater smell mixed with those Engines! Intoxicating! The the Elsinore! BEST Decade of my life! On Any Sunday! Those Husqvarna 400 Cross! Unreal! Best Times Ever! Fond Memories Sorely MISSED! God Bless...😊😊
"Different Strokes for Different Folks" · Yamaha 1971
I was there
Nice...
And the rd350 will remain my favorite 2 wheeled vehicle of all time, can't wait to find a new one in good condition near where I live so I can blow a check on it lol
tyee🎉Tyr tryyytyttytr type of you 🎉🎉Ty yuyy y🎉yay 😅
Damn they were woke even back in the day.
As a dirt bike AND snowmobile guy. I feel it’s important to point out that the winter guys have been doing crankcase and transfer port EFI since the early 2000’s. And more recently direct injection two strokes for more than a decade. Both BRP and Polaris have recently introduced turbocharged EFI 2 strokes making around 200hp per litre. There is a lot of potential in two stroke fuel injection. Hopefully other manufacturers catch on to the demand.
Yes sir came here just to say that E-TEC is absolutely a direct injected 2 stroke. That technology has existed under BRP for a long time now.
And why this technology can’t come to off road bikes, and even better street bikes I have never been able to understand
@@victorvannatter312 It's very expensive, complex & heavy, complete opposites to why manufacturers love 2 strokes for (cheap, simple & light very important on motorcycles), and it involves a lot of engineering by each manufacturer to make sure they don't get slapped with patent lawsuits, plus even 4 strokes are now having trouble passing modern emission norms & EVs taking over, it's extremely difficult for a 2 stroke engine that burns oil, to pass.
My 01 cr250 Honda is the fastest machine on the planet beat NASA and all them people with it 1000s of hp way more American and reliable than Harley garbage and 4jokes if it don't smoke it's a joke
@@BrattyBikeremissions don't matter when they can't keep up helicopters are no match
A great video covering my motorcycle youth. Two strokes were a blast. I wisely kept my last two stroke, a Yamaha RZ350. I still have it, still ride it frequently. I will never sell it. Having too much fun every time I ride it.
As someone who started off with a 78 RD400 there is something about that burst of power and cloud of smoke you leave behind that you never forget.
2 Strokes are the most simple motors to work on. As a young kid, you could swap pistons with a one socket wrench.
The main problem with owning a two stroke is that they are not very fault tolerant. If something's wrong then they tend not to run at all where a four stroke will run rough - which tends to be easier to trouble-shoot.
When I was at college, a friend and I tuned up an MZ 150. In stock form it did 60 mph and 60 mpg (UK gallons). When we finished with it, it did 80 mph and 80 mpg (with a very sharp power band). Happy days.😄
Bart, you have some of the very best videos. I grew up in the golden age of two strokes, My rides included Kawasaki, Suzuki, Yamaha, Bultaco and Ossa. I now ride a four stroke under protest.
Videos
You don't like head?
A buddy of mine had Baltaco, I never heard of before. It was a monster! I have never forgotten it!
@@waynez1025 I rode a Bultaco with a bored out cylinder. I think it was originally a 350 but it was as you say a monster. Incredible acceleration up to a speed I never attained. I was scared of getting busted
Ossa had this sublimely beautiful 500cc twin that i`ve only seen pictures of in the `70s! Apparently it was never really fully developed but she was a JawDropper! If Only !
My grandfather was back in the day one of germanys best Trialriders, once on a raceday a friend of him crashed with his DKW (he was a factory rider) and unfortunately damaged his exhaust, because it was a little sport and money was rare he had no other exhaust to change. But he got extremly lucky because the dent helped the engine to gain 2hp more, so he won the race.
Stund by this happening DKW tried to replicate the dent for all there Motorcycles, but it never worked out on a cheap basis because the dent was far to complex to machine for the time
I have a DKW car! 1965. The exhaust is part of the compression system of the engine.
@@facbl 3=6? or what car is it? I'd love to see and hear a DKW 4=8....
I love 2-stroke street bikes! I have owned several. The last one was a 1984 Yamaha RZ350. This was the last street-legal 2-stroke road bike sold in the USA. It even had catalytic converters as a last-ditch attempt to pass EPA regulations. I promptly ditched the catalytic converters and replaced them with Toomey expansion chambers. It cut 30 pounds and added about 30% more power. Sadly, I sold it about 20 years ago. I would love to have a modern high-power 2-stroke street bike.
I bought a RZ350 in 84 after growing up riding RD350's and a RD400, it was the best two-stroke street bike ever made. Now I live in Cedartown, GA. where KTM has a bike park called Highland Park/KTM World. You can rent a bike for the day and they have the motocross track and a bunch of cool trails, you can still get your two-stroke fix if you want.
I had no idea that two strokes were not street legal in the US anymore, that’s tragic
@@MrCrispyNips04 Yes, the US had the equivalent of somewhere around EURO 3 emission regulations by the mid 1980's. As far as I know, all the 2-strokes now available are off-road only. Some States, like California, have even stricter air emission regs for offroad-only motorcycles on public land. For a long time the US had stricter motor vehicle emission standards than the EU, but that changed with Euro 4 and 5.
I've got a 2001 Honda Elite SR. I'm not sure if you'd consider that a street bike, but it was still legally sold in the US for on road use and it is a two stroke. Yamaha also sold the two stroke Vino until the early 2000s
@@middlesiderrider A lot of Ststes exempted 2-strokes under a certain displacement. Often, 50cc was the limit. Some mopeds and scooters were exempted as well. In NC anything under 50cc did not require a license, as well. I recall a friend who had his license suspended buying a 50cc moped and installing a 100cc "big bore kit", hoping that no police would notice. They didn't.
Veteran 2-stroke maniac here. I started at 15 years old, with a Puch Grand Prix, which used to do 65 mph. Then progressed to a Suzuki X5 200. I also owned a BSA Bantam 175, then my all time favourite a 1974 Suzuki GT 750, which I bought in 1982 and sold in 2003. I had a knack for finding that extra 5 or 10 mph out of a 2-stroke, all my mates used to bring their bikes to me for a tune and tinker, to get every ounce of power from the bikes potential, playing with the jetting, exhaust ports, different spark plugs, different exhaust pipes, etc. Happy days!
I just want to say, as a fellow motorcycle lover, I absolutely love your videos. Keep up the great work!
Thanks!!
@@bartmotorcycle The Rotax ETEC direct injection voice coil two stroke engine is alive and well in the snowmobile world. Skidoo has been using this engine to power their snowmobiles for more than a decade. There's even a turbo-charged version for high altitudes. Welcome to the 21st Century!
@@bartmotorcycleBart, I appreciate you at least mentioned MZ but how can you skip, even in passing, the legendary Jawa and CZ? Especially CZ as a dirt bike.... Sad....
BTW, I have a 1970 Jawa with a Velorex sidecar
@@bartmotorcycle People Must get Educated, that the Global Warming Is Absolutely Not connected with the Global Pollution !!! ! !!! These Are Two Entirely Separated Processes !!! ! !!! Just as the Global weather catastrophes Are Absolutely Not connected with the Global Warming. Peace with you.
I ride 2 and 4 stroke machines, but I have to say the 2 strokes are more fun. I love the violent power delivery--nothing beats a 2 strokes when you're on the pipe. I also love the smell and the sound. They can be more challenging to ride fast because the narrower powerband, but that's also part of the fun.
to bad you dont know any thing at all of how or why a two stoke operates and you dont have a clue of what you are trying to explain what it is being on the pipe or in the power band
I had a 1976 Suzuki 750 CC "Water Buffalo". Great bike, was trouble free. I got teased a lot by friends who rode big Kawasaki or Honda 4 cylinder bikes, but held my own with any of them.
They were very good. I worked as a mechanic/service manager for a dealer upstate from NYC and we sold a few of them. They were prone to puddle lubricating oils in the mufflers and I had one actually catch fire in the mufflers on an extended road test where I could run the bike hard for a few minutes. I think the smoking and associated inconveniences went a long way to causing them to lose appeal. The new GS four strokes were more civilized in most ways and customers responded to that as a positive against the two-strokes.
@@danielklopp7007 I put expansion chambers on mine as well, but did not rejet it, so I had to watch it, or I'd run it too lean racing. It would pull huge wheelies with those tuned pipes.
"I had a 1976 Suzuki 750 CC "Water Buffalo"."
Know in the UK as "The kettle".
Having raced against them I can say they were faster than were given credit.
From the Mount Rushmore of Rocket League, to becoming a top tier motorcycle historian. Proud of you, my guy. Your passion for bikes oozes through these vids.
3:15 Expansion chambers don't force "exhaust back into the cylinder". The port timing is such that fuel/air mixture is allowed to pass through the cylinder & into the exhaust tract. Then the inlet port closes & the resonance in the expansion chamber pushes the fuel/air mixture back into the cylinder. The exhaust port then gets closed off. It's a kind of supercharger with no moving parts.
Never really thought about it before, but the design, and function, of the expansion chamber shares a lot with the way a pulse jet works
@@peterbradburn9115 I suspect that a lot of the knowledge gained from Germany's WWII pulse jets is indeed what led to the expansion chamber. They used pulse jets on the V1 "buzz bombs" and were trying to use them for manned aircraft as well.
@@retiredbore378 The development of the exhaust "power valve" allowed the dimension of the exhaust port to change, improving efficiency and reducing emissions somewhat.
I always understood the function of the expansion chambers as being able to "pull", by means of resonance and exhaust gas flow, more fresh fuel/air mixture into the cylinders. Kind of how the condenser of a steam turbine creates a vacuum.
@spaceflight1019 My understanding is that when the engine is "on the pipe" as we used to say, the exhaust pulse is reflected back up the pipe to both block the fuel-air mixture from exiting the cylinder and providing a suction like effect when the exhaust port is opened to help scavenge the burned gasses. Needless to say timing is critical and that is why the rpm power band is narrow or limited. A 2 stroke capable of revving to 10K rpms my only produce high power over 2K of rpms.
Brilliant brilliant video. You covered the issues so well. As the owner of an RG500 street bike it was music to my ears. I've always preferred 2 strokes to four. Probably because I've not typically had bikes to just go from point a to point b but rather for the fun only a 2 stroke can give. Btw the RC211V was a V5
Nice something about 2 stroke from a knowledgeable guy like yourself, I personally have a mz etz (125 but looking at upgrading for more power😃)
Well Mr. Bart I have been riding and racing “them there “motorcycles I would guess 2 times longer than you have been alive. I am here to say you do a wonderful job making your videos . Thank you.
This video brought back so many memories! All of my early bikes were Suzuki 2 strokes - started off at 16 years old on a metallic red 1977 AP50, then went on to a GT125 twin, GT 350 Rebel, and GT380. Virtually all my peers also rode either Suzukis Yamahas or Kawasaki 2 strokes
Still remember the evocative sound and smell of a multi cylinder 2 stroke on fast choke idle first thing on a chilly morning...
Good times
As a 2-stroke fan who owns a few of them, this was a great video.
Nothing will ever beat the sound of a two stroke triple running on his expansion pipes.
And a 3-1 pipe, with a huge middle channel, might not be the best for power, but the sound.....
My first vehicle was a 79 Yamaha DT250. Loved that thing. Rode it all over the Black Hills trails and back and forth to school. Not exactly a speedster. Top speed of 55 if I remember. Obnoxiously loud. And hella fun. Good memories.
My first vehicle at age 15 was a '79 DT125 with 20k miles when I got it. It topped at about 55mph...until I cleaned out the carbon in the baffle and a few other things like new rings....then it almost could do 80!
@@empireoflizardsYes. Yours 125 -80,his 250-55😂
I could go 65 MPH on an urban freeway on my 55cc 1975 Yamaha RD60 2 stroke.
@@empireoflizardsTV by FC
Seriously how good is this channel? Bart is THE Motorbike historian!
Just can’t take how he says yamahawwww
Except when he refers to the Kawasaki 500 triple as the "H2" (sic) instead of the H1.
jf he is a motorcycle historian he is telling a tale that apparently he has invented on his own that never happened in order to gain subscribers that equals money for telling you anything he wants weather it happened the way he said or not ! the thing is i am older than dirt and have lived through all of his spoken history so i can tell instantly if what is said today happened or not simply because i was there and most all of you were not
I owned a 500 H1. I'm sorry I ever sold it. Out of all the bikes I've owned, it was my favorite. Handled like crap, but fast in a straight line. Great bike.
regret that decision and be sorry!
RD350 that’s all ya gotta say.
Thanks for sharing about the Resonance effect.
That was the height of the development. A neighbor had one around 1980 and never forget the start up, plus it was light and maneuverable!
I started with a Yamaha 80 in the SoCal deserts. My cousins raced 250s.
Interesting video! One thing you didn't mention was the Suzuki GT (380,550 &750) series which were effectively grand tourer 2 stroke triples. They were tamer than Kawasaki triples but the GT750 is one of the most sophisticated 2 stroke bikes for its time and potentially ever made which is why it is officially one of the 240 Landmark of Japanese Automotive Engineering.
I had a couple of the 380s and a 550 back in the 1980's. My friend had the 250, which was a twin instead of a triple. I never did get to try the 750 model.
Had the GT750 in 74. Water Buffalo!! Screaming fast!
I had the GT380. A most civilised and long-legged machine. A police car totalled it, and nearly me as well but the payout bought me my first Goldwing. Now I wish I had the GT back...ah well.
@@chrispomphrett4283 I was a dirt bike kid so I was surprised that a two stroke was built to be a touring machine.
My father GAVE AWAY my last 380 when I joined the Army in 91. He apologized later by giving me the money for a HD chopper though.
My old Kaw S3 400 is still the most fun I've had with my cloths on! Wish I still had it.
Know the feeling! I had an S2 350. Getting it started on 2 cylinders first...and then blipping the throttle so the centre one would kick in. Becoming expert on setting the points with a cigarette paper and transistor radio interference. Would match an R5 but not an RD. Kwackers still looked the best though..
My first bike was/is (I still have it, several bikes later) a barn-find 85 Suzuki AX 100R. It has no battery, makes a pittance for power, and is about the fourth most fun bike I've ever ridden. It's a riot - loud, smoky, accelerates like a stabbed rat and has a ridiculous powerband where nothing happens for most of the rev range, before ALL the torque and power kicks in. It weighs 78kg, and even though its got a slow top speed, it's great fun. I'll never get rid of it.
This is an extremely good story. I myself have been a 50cc racer for 10 years in the 70's and early 80's. I've enjoyed it. You also brought in Kaaden very thoughtfully because he was the man.
Couldn't agree more.. :) My younger brother had several Kawasaki 500's , widow makers. I had several Suzuki T500's. The Kawasaki was mental, the Suzuki not as much but handling was light years ahead.
Kawasaki 500cc will do 130mph with a little guy laid flat,INSANE SPEED for the 70s H1 monster power 🔋
Having started out on 70s Suzuki GTs, I've always been sad about their disappearance - this was a good essay, thanks! How about a deep dive into some of the specific technologies that drove 2T engines forward as innovations? Eg - power valves, reed valve inlets, resonant exhausts (expansion boxes), water cooling - that would be *very* interesting for an old greybeard like me 🙂
The 70's four-stroke GT's motors had a unique clattering sound. You could always tell it was a Suzuki coming without looking. I asked a mechanic/builder friend (whose work was in the magazines of the day) what was up with that sound. He told me that Suzuki used "extremely thin piston rings."
TSS of Australia were producing an 1100cc two stroke triple a few years ago that made 250 wheel BHP. They fitted one in a Kawasaki ZX10R frame.
I love the fact that when you showed the top muscle bikes from the magazines at the 5:20 segment, I owned 2 of those motorcycle's, almost, In 1977, I had a Kawasaki KZ1000 but when the Suzuki GS1000 E came out the next year, I traded in the Kawi for the GS, just so I could say I'm driving the fastest motorcycle in the world for 2 years in a row. I worked a lot of shifts pumping gas for 2 years so that I could buy that Kawi at the age of 18.
One of my biggest regrets it selling my RZ 350 with a Toomey set up. Awesome video, the attack with handicaps blows, didn't realize it killed both gp and dirt.
Bart made a good point when he stated that the race organizations and motorcycle manufacturers wanted the race bikes to be closer to what was being sold to consumers. Things may change if several manufacturers are able to develop 2-strokes that meet various emission regulations.
Formula 1 in auto racing took another tack and their engines are supposedly the future of street technology (hybrids with energy recovery and reduced fuel consumption).
In the sixties, Bridgestone made motorcycles. One bike in particular was the Bridgestone 350 GTR. It was more expensive than the other Japanese offerings but it was a fantastic motorcycle. It used nickelsil in the cylinder liner and was overall very high quality. I suspect Bridgestone quit making motorcycles because they saw what was coming down the pike regarding emissions and rather than focusing R&D on development of a four stroke Powerplant, decided to just stick to producing tires.
It also had rotary valve induction like a Can-Am and some Kawasaki's.
I think the bore was chromed. Nikasil came to use later. I also remember reading that the other Japanese motorcycle manufacturers threatened to stop buying Bridgestone tires unless Bridgestone exited the motorcycle market.
Bridgestone quit making motorcycles because they were held accountable for stealing other manufacturer's patents.
@@kmoecub I've never heard that one before. What were the patents?
My understanding was the big four declared: "If you want us to keep buying your tyres for our motorcycles, stop making the latter". Bridgestone made a lot more money from its tyre making than motorcycles so it made good fiscal sense.
My elder brother had a 1976 Jawa 250 two stroke motorcycle.
He had painted it in red color by himself and used to tune it.
I still remember the sound and look of it sometimes.
Your consistancy amazes me, all the stuff you've posted is high quality; BTW I love the old b&w archive pics and film. People may have been even more goofy back then than they are today. Makes me feel right at home.
My first bike was a used, 70-something Suzuki GT-250. Man, that bike was a blast to drive and it was bulletproof reliable. Great sound and fast revving. Wish I could have kept it.
Man, I’ve been advocating for 2T engines for my whole life, and I’ve been really pissed ever since they wiped them out because…well, hype. This video gives me HOPE, for I assume you’re a young guy who actually appreciates what’s behind riding and competition. I owned 2S in my youth and 4S in my not so youth and man, what I’d give to have that scream and oil smell from 2S back in the streets again. Thx for this. Keep it going!
Bro! 👍
Great video, thanks.
I have been a biker for nearly 50 years. I loved my Triumph twin and I loved my Honda four. For lightweight fun, whether scratching twisty back roads or commuting, I still love my MZ 250 (the only bike I currently own, although I have the occasional use of a Yamaha 1300).
Emissions regulations targeted the two stroke engine by focusing on unburnt hydrocarbons. Interestingly, the traditional two stroke does rather better than it's four stroke brethren on oxides of nitrogen...
I think it's sad that you never mention Kreidler when talking about 2-strokes. The Kreidler Florett bikes were fast, comfortable, extremely reliable and so insanely beautiful. Legend says that the reason they went bankrupt was a lack in sales of spare parts. Anyways good video as always.
Seriously how good is this channel? Bart is THE Motorbike historian!. "Different Strokes for Different Folks" · Yamaha 1971.
I remember my older brother telling me about a friend of his who, after having exclusively British bikes bought a Honda CD175 (4-stroke twin) brand new. He complained that it was smoky and kept breaking down, and blamed this on 'low quality Jap crap'. Then I got to the truth - turned out he was told 'All Japanese bikes are 2-strokes.' Where he got this from who knows? So I realised he was putting oil in the tank with the fuel (all 2-strokes at the time were pre-mix). Which neatly explains the smoking and the unreliability...
Enjoying your videos. I’m from the 2 stroke race generation. I’d love to see them come back.
Two stokes are awesome, I remember when they rev out as you run out of fuel, as you frantically try to switch to reserve, and of course the powerbands, nothing compares
bruh this just literally happened to me today. I have a Kawasaki HD3 125 cc two stroke motorcycle and I forgot that I've set the petcock to main instead of reserve. As I was cruising down the road, it immediately revved so high that I thought it would blow out. Just knew it through this comment that two stroke engine do that!
I grew up riding two strokes, they were fast and fun. And I loved the power band. Couldn't beat the feeling
I still use a 2 stroke mainly cause I enjoy the powerband
As someone who drove a MZ250, I was surprised to hear about MZ's part in the rise of two strokes. Didn't know that. Thanks for the info. 😀
Nice video as Always! I would like to add a small correction at 10:55, the RC211V was a V5 engine not a V4, this V5 engine was an amazing piece of engeneering and was very dominant in MotoGP, with Vale the bike was unstoppable, but the Doctor managed to win against this beast in 2004 and 2005 when he was riding for Yamaha, then after Nicky Hayden became a MotoGp champion for Honda in 2006 the regulations changed and no 5 cyl engines were allowed.
Yea it was really fair competition having 5 cylinders against 4.
Great video I was a bike mechanic back in the 70s built A lot of RD 400.
And Had several Kawasaki triples. I still remember doing wheelie's past AZ1R.
On my RD4 hundreds. In the quarter mile
Growing up me and my fellow degenerate teenage friends rode around town on our scooters, souping them up, crashing constantly, off-roading, and swapping parts when we bent the forks in or found a bigger front tire, etc. my buddy had the only one with a two-stroke and it was so mysterious and incomprehensible to me, foreign almost but kind of awesome
and they'll run backwards! We never put it in gear, just wanted to prove a point. Degenerates unite!
I had a Yamaha Fs1e 49 cc 4 gear 2 stroke moped for 2 years & loved it. Great vid & sounds encouraging for a possible 2 stroke comeback.
I owned a 50cc scooter and I gotta say that thing made me hate two strokes. Slightly clogged jets in the carb? Piston gets fried. Failing oil pump? Piston gets fried. Going top speed for a bit too long? Piston gets fried. And man how moody it was to start depending on the temperature was annoying
youre talking 50 yrs ago! get a Kawasaki 150cc proper modern 2 stroke single cylinder liquid cooled little rascal bike today and see the difference!...
@@fidelcatsro6948 i bet water cooling and fuel injection makes all the difference. The scooter wasnt even that old. It was from 2006. Theyre just poor build quality. Everytime I see that model standing around somewhere I always find the same puddle of oil I had under mine
@@BlogVomMax Vespa?
@@fidelcatsro6948 not a vespa but a piaggio fly. Quiet the shitbox
@@BlogVomMax not suprised then!
My first motorcycle was a used Yamaha RD200. It was a nice little motorcycle, though the clutch died after one summer of hard driving in rush hour traffic. Never had a two-stroke after that, but it was a nifty little street bike.
nice video but the Kawi 500 was the H1 and the 750 was the H2
I learned to ride on a Yamaha RD 350..it was great fun..stil love this bike! Thanks Bart!
It is important to keep the performance of 1960's and 1970's motorcycles into perspective. I liked the Yamaha RD350 and RD400 two-strokes. They were considered fairly high performance at the time. but if you look at the acceleration and quarter mile times, they were slower than the current Kawasaki Z400/Ninja 400.
You are correct. But imagine what an RD400 with today's tech would be like, it's sounds like an inviting proposition.
@@darinhampel4149 Yes, some places outside the US got the next couple of generations of two-strokes with "power valves" and by all accounts, they were a lot of fun. Yamaha did not do a lot of exhaust tuning to their 2-strokes for the street. I suspect that it was to spread the torque over a wider area. I have read that the RD350's and RD400's were very different with tuned expansion chambers. They had a lot more power but most of that was in a narrow RPM band, making them difficult to use in traffic.
@@jfess1911 ugh.. traffic, it ruins everything! (Except Frogger)
Oh, but that's not true. It's not the CO2 that is causing the smog, it's the uncombusted fuel that is ejected, the lubrication is being burned off, up to 170x more hydrocarbons, 10-20x more carbon monoxide, up to 8x more nitrogen oxide, and more particulate pollution.
These things are what cause smog, and all those 2-strokes were a major contributor.
Remember, you said it yourself - a restrictive exhaust on a 2 stroke, such as a catalytic converter which removes a lot of the pollutants, reduces the only reason anybody would ever run a 2 stroke, greater power for the displacement.
There’s nothing like the smell of Castrol R two stroke.
Klotz smells pretty good
With Cam2👍
We used to own/ride a two stroke 1986 Suzuki A100, and loved it !
I still miss it sometimes.
I love the feeling of driving two stroke motorcycle.
It's the burning oil the real core of the emission
Your the ignorant one spreading misinformation. That's not true. Get a life.
@@theenzoferrari458 So.... what happens to the oil injected into the engine? Where does it go?
I agree 100% on 2 strokes & government intervention. Well done video!
the government focks up everything it touches!!
I still have my 1973 RD 350 bought it new in 1973 for 847.00 dollars out the door price.
make a video and show us amigo!
Owned the 3 banger Kaw corn-popper 50 years ago....and am lucky to be alive....loved the vid. Lottsa memories of the many 2 stk's I have owned
There have been direct injection two stroke outboard engines from both Mercury Marine's "Optimax" series and Yamaha's HPDI (high pressure direct injection) series, as well Evinrude's "ETEC" series, for over the last 20 years... Direct injection is not "impossible" with 2 strokes as you said, and is very common in 2 stroke outboard marine engines, and only now in the last few years have they been getting phased out due to CARB standards, though many still remain...
The smell of Castrol R will always bring memories flooding back of TZ'S for me.
True. It did tend to clog up the exhausts on road bikes with separate 2 stroke lube tanks. Possibley due to its veggie origins rather than the mínealaíon for whoch they were designed. We took to daubing a little daily on the exhaust tip to keep some remanant of the smell. Then Esso (Exxon) a bit player in 2T lube came out with a mineral oil that smelled almost like the real R. .......
I always found Jawas fascinating due to being so different from popular Japanese bikes (USA). Every report I've seen on the 350 had about 21 horsepower and the speed/acceleration numbers reflected that. I would love to hear more about any version boosted to 34HP.
You will not get it from the real Czech Jawa, that's for sure.
The Indian + Chinese stuff is great, though.
I just discovered your channel and have really been enjoying the content! There is a LOT of motorcycle-related stuff on RUclips as we all know, but not a lot of motorcycle history. I can pick any one of your videos and at least 90% of the information will be new to me. You're filling a niche and doing a great job of it-keep it up!
I remember my old RD-350 back in '73... lightweight and so much acceleration it would backflip you on takeoff if you weren't careful. Even the new monster Kawasaki Z1 knew not to bet against the RD when coming off the starting line. If I remember correctly the RD had 46hp; for comparison the popular Honda CB350 had 25hp. For a motorcycle the two-stroke RD got really crappy gas mileage even if ya babied it.
excellent video, i grew up in the 70s on two strokes and its such a shame that kids will never experience the feeling of a time when ALL dirt bikes were 2stroke, theres nothing like the sound of a 2 stroke hitting its powerband!
My daily ride is a 1977 CZ 350-472.1 Sport 2 stroke twin. My 33 year old son's daily ride to work is a 1974 CZ 250-471.0.005 Sport 2 stroke twin.
3:51 Small correction: he defected from EAST-Germany.
Bart; this has to be your finest video yet...Keep it up.
The simplicity of two strokes is so beautiful. Improving the emissions is such a major advancement, because they did it while simultaneously improving the torque curve and widening the power band. Simply amazing. I agree, there is a real future for two-strokes again. Even if they continue to only be used in enduro, maybe motocross again, and scooters, the improvement of pollution in asian cities (and thereby all air) by scooters being upgraded to modern EFI 2T would be significant. Also, the production carbon footprint of 2Ts should be drastically lower compared to the 4Ts, which require so many more parts and production steps/time. I even wonder if tiny two-strokes could be used as on-board generators to recharge a battery in an EV on the fly, for an insignificant emissions hit, to keep from having to stop for slow charges or swap batteries. Might be a worthwhile trade-off, allowing for a place for fossil fuels used very efficiently and reducing demand on coal-burning grids, while solving the range and recharge time problems.
I love your ideas for modern 2 Strokes. Mazda is doing something similar on EVs with a rotary. Things to think about for sure!
Would love it but as long as you're burning oil the emissions will never drop below a 4t
I've had two stoke motorbikes in the 70 s' and there is nothing like them. For me a 1970s' Japanese two stoke motorcycle is unbeatable - bring them back!
yes please, something about 2 strokes!!!!!!!
here you go amigo-> waaaang waaanng ting ting ting
I have a near mint Yamaha rz500 I purchased new in 1985. Still have it. I'm 66 and learned to drive on 2 strokes. Love them 2 strokes.
RC211 was a V5
I did have a Yamaha 250 cc 2 strokes bought barely used in '73 and I loved it. Light, fast and a great handler.
2 strokes forever!!!
I personally cant stomach 2-strokes, because I associate them with mopeds, just because of the sound and the smell. 4 stroke sounds so much more powerful and grown up, but yeah that is me that. Honda mt5, yamaha dt50, banzai :D
To my ageing ear, nothing beats the sound of a >250cc two-stroke twin in full cry.
Ever smell Castrol blends all ?? Ah, the days of my youth
Take the suter 500 mmx 2 stroke inline 4 576cc engine. Makes more power and weighs lighter than the new kawasaki H2R and that's a 4 stroke 999cc inline 4 motor. Tell me who's more grown up now ignoramus degenerate?
You weren't riding the right machines then. When I hear and smell two stroke I think of power. I've ridden some absolutely rowdy two stroke motorcycles and snowmobiles. Nothing like a good two stroke!
@@Friscorockhead does not really matter if I have ridden the right machines or not, if I as an 15 year old teen rides mopeds then ofcourse I will associate 2-strokes with mopeds ie bikes for children. I have ridden 125 and 250 2 strokes "gp bikes" and still every time I put my legs over such a bike I still get reminded of 2 strokes being mopeds. Nothing to do with them having power or not. That is my nostalgia.
I grew up riding 2-strokes; dirt and road bikes that were absolute pocket monsters. In the late 80s, I had the privilege of owning a Husqvarna WR400, and a works Yamaha RD350LC. With their utterly vicious power band, I was completely gob smacked every time I rode these bikes. Once they hit the sweet spot on the pipes, it was like the old THX sound demo where the individual notes are jumbled and disorganized until they all come together to make the perfect power chord and all hell breaks loose. 4-strokes make ridiculous power these days, but 2-strokes are an addiction.
~9:50, on handicapping. I moved from the Midwest to NYState in the early '60s and ran into this peculiar thing: The racing class I was involved with there pitted 200cc four strokes against 250cc two strokes, just backwards from what's covered here. I rode a 200cc Parilla Wildcat against 250cc Greeves, CZs, which were the most common two-stroke competition scrambler bikes at the time and wasn't beaten by any two stroke bikes. Within a year, the classes were restructured and with that, I began to compete on a 250cc Bultaco. At that time, they separated the classes by engine type so I could still race the Parilla but only against other four-strokes up to 250cc (and it was still competitive). The two-stoke scrambles and motocross classes took off with rapid improvements in the machines.
Do you remember roughly when the 2-strokes began to improve dramatically? I don't recall when I started seeing expansion chambers on them and recall that even mid 1970's two-stroke street and "enduro" (dual sport) bikes tended not to have them. I suspect that it was to keep the wide torque band. The highly-tuned 2-strokes tended to be nearly unrideable since most of the power was in a narrow RPM band. The introduction of the "power valve" in the 1980's helped greatly.
@@jfess1911 I suppose it depended some on one's location. For me, in Kansas at the time, it was the arrival of Bultaco machines in 1961. They had full expansion chambers (Sherpa S models) and put out serious horsepower. Two friends of mine were trying to start a dealership but didn't have the resources to build it up to be a good competition shop. I took over the purchase of a 175cc model when the original buyer failed. It was competitive with most 250s but developed issues and I sold if off as I was relocating to the NYC area in a month or so. High performing two-strokes were rapidly gaining use in the West, that was '63. Within a year I was sponsored on the Parilla but the owner was planning on importing Husqvarna and had one of the early issues which was a very promising machine. Twin pipe CZs were showing up regularly as well as improved Maicos at about the same time on the East Coast and the power battles really began when the Bultaco Metisse 250s started showing up in '65.
It took a good deal of experimenting to tune expansion chambers on street bikes and we never got involved with promoting it. We occasionally took in bikes that the owners had attempted their own tuning. We didn't have the facilities or number of personnel to take on ambitious projects. We dealt mostly with good service for new machines.
It's worth mentioning what it took on those early machines to make them fit for their purpose. Bultacos had to be lubricated with Castrol R 40 which was mixed with acetone so it would blend with gasoline. Also, the stresses were popping up weaknesses and our one 200cc Sherpa S lost its wrist pin bushing starting the second season, they didn't yet use needle bearings in the con-rod top end. There was a break in process that included pulling the head, cylinder and piston, and sanding any shiny piston scuff spots to ward of seizures.
@@whalesong999 Thanks. I didn't start paying attention to motorcycles until the 1970's and was aware that various race machines had expansion chambers but many other 2-stroke motorcycles did not. I rode a Yamaha AG175 farm bike from the early 1980's and it still didn't have an expansion chamber, for goodness sake.
@@jfess1911 Utility bikes really did well with muffler systems that were developed concurrently with improvements in the engines themselves. I had a Bultaco Matador, and enduro bike, that had a rather simple muffler system but still had plenty of oomph to successfully compete with outright race machines if ridden well. Later on, I rode a 230cc OSSA Pioneer and it also had a very good muffler/expansion chamber. When I first took an interest in racing, some riders were simply removing the entire mufflers and just letting the header pipe exit with no restrictions. The performance actually worsened, only the removal of the weight had meant any advantage.
@@whalesong999 The Yamaha AG series was designed for agricultural use rather than the street. It pulled well at low revs and reportedly had only 13.7hp according to a Yamaha advertisement. My understanding is that it used the older CT3 engine and though a 1983 model, still had dual shocks. It was asssigned to me when I worked in Marrakech Morocco, so it was often used in 100+°F (38+°C). I never seized mine, but others did since they largely ran them full throttle to keep up with traffic.
Some random thoughts:
Imagine an expansion chamber exhaust system on a Scott? If only...
Stock exhaust system or expansion chamber system- none sounded good to the average person...
Doesn't hurt anything? Only one commenter here mentioned (S.E. Asian countries) pollution. You have to experience the pollution in the major cities of Thailand, India, China, Philippines etc. where 2 stroke motorcycles are sold...
Can anyone settle a 50+ year old bet about a Bridgestone motorcycle hand throttle? One said the twist throttle worked conventionally, the other said counter-conventionally...
Great video young man!...
Mythbusters tackled the myth of motorcycles polluting less than cars in s09e13. The verdict was that motorcycles polluted more simply because there's less room to add components and units to eliminate the emissions on a bike than a car.
Ring-a-ding-ding! Great video as always. I really enjoy your focus on history and writing. Bring back the 2-strokes!
In the early 1970s, I rode 2-Stroke motorcycles exclusively. If I was to ride a 2-Stroke now, I would crash out!
this reminds me of may dad's stories about hillclimb racing in his dune buggy. there were two racing classes: the kids who could afford "paddlewheel" tires, and the poorer kids who would weld two wheels together and spread one tire over two inner tubes to get a wider contact patch. there wa sone weekend he was the only one who showed up without paddlewheels, so they talked him into racing in the paddlewheel class, and he said he would never make that mistake again.
similarly, requiring four stroke and two stroke to have matching displacement does give the two stroke a significant advantage. matching them by airflow or fuel flow would make for a closer race.
Back in the 80's I owned several of the Suzuki GT series two stroke street bikes. I had a couple 380 models (they kept blowing up the middle piston) and a 550. My friend had the 250 version which was a twin. The '76 model had a digital gear indicator which must have been fancy in the 70's. I took one of the 380's and put on drag bars, made rear-sets in shop class, and found a 3 into 1 exhaust at a junk yard. It was still pretty slow. Sounded like a popcorn popper at idle. Smoked like a chimney at high RPM but was fairly smooth at reasonable RPM.
Then I got to ride a full race RZ350 a friend owned and man was that thing a blast. Basically a Banshee motor in a sport bike.
Not exactly, the Banshee was an ATV with an RZ350 engine.😂
In the beginning of my riding I rode the old four stroke scramblers. When the two stroke motocrossers hit our shores I moved over. I basically rode nothing but two strokes from the 70’s-90’, But I was riding off road as a racer. When I changed to the street is when I moved to the big four cylinder four stroke machines. I love them both, just depends on the application your looking for. Some applications need more smooth torque, others more instantaneous hp.
Too powerful for man
we weren't ready
i regretted the loss of 2-strokes, light and simple were powerful attraction. but they smoked. sigh.
relax, people, the future is electrical. no smoke. great torque. you'll get used to the silence.
2 stroke outboards by both BRP and Mercury Marine have used this technology for over 10 years and can meet the latest emission requirements.
Absolutely. Love 2 strokes. Had Bultaco, Montesa, Ossa. Light, fun and fast!
I started with a 72 Suzuki GT380 back in 1977. Previous owner had ripped it apart to fix a points problem and had a garage fire where several major parts were destroyed. Got for a song and rebuilt it. Started on the first kick (may have been the second kick) and as described by another, took off like a stabbed rat. Rumoured it could out drag a Porsche 911. Had to sell it when posted in Germany. Insert tear here.
Current bike is 93 CBR600F2 (AKA GOOF2) and also moves but I still remember rides with buddies (one had a GT500). Thanks for the article. I'll look for others.
Excellent presentation. Your points are absolutely valid ones and I can't imagine anyone not agreeing with your logical opinions. Thank you.
Out of my all bikes the one with two strokes I love the most. Thanks for the great vid. I learnt a lot of useless trivia from it! :D
It is cool that you love your bikes. I have had riding buddies that also loved 2 strokes. I've ridden them and for whatever reason it was not my cup of tea. I did not find powerband helpful but I do see it is thrilling. I preferred the 4 strokes for the more predictable power delivery. Really cool video!
My Dad and I are trying to restore his '73 Yamaha AT3 to rideable condition. Because old-school 2-Stroke awesomeness. We call it "The Landlocked Jet-Ski" because of the noise of the power pipe. Been a lot of work already and finding a gas tank that wasn't rusted out or dented to pot was a royal PITA, but we're (slowly) getting there! Wish us luck
Thanks for brining back the memories.
Great video. I had a 1971 Suzuki T-500 two stroke. It had a wide torque curve. It used transmission oil like a 4 stroke. I remember riding it through Riverside, CA (just east of Los Angeles). My eyes were burning and tearing up and it was hard to breath. California has already planned the end of all internal combustion engines. Well, everything has advantages and disadvantages.
Yeah, and we have rolling blackouts because the electrical grid isn't strong enough. How are they going to charge these damn things? Maybe hydrogen motorcycles?
You mentioned the one weakness of Suzuki twins, using transmission oil. Not all came to that but it began with the 250cc T20 "Hustler" and since they all were developed with that basic architecture, the weakness followed. It was a good idea, having transmission oil to lube the crankshaft main bearing on the drive end (the T20 had that feature for their center mains as well) but the quality of the seals is what caused the deterioration leading slurping up some of the transmission oil. IIRC, we had a time where Dexron automatic transmission oil was specified and that was a good solution because it helped the service life of the seals.