see aptera owners club video on saftey, heavy cars make it less safe for lighter cars but heavier doesnt totally mean safer, and join the disc ord server in the description box under the video, my name there is animate mental terrorism
You can increase bore and not raise displacement by reducing stroke. Proof of Honda doing this in reverse is the difference in The SC 57 Vs SC 59 CBR 1000rr.
me too. just like when google first emerge, they do things differently. they made a lot of freebies for internet user. they were trying to experiment with a lot of internet things. i remember we talk a while back saying, eventually you see big companies go to space once they have the capital to do so. i remember saying, honda is one of them as they are a very stable company and they do a lot of research and development of new tech just like asimo. now you have blue orgin and space X. elon musk, is experimenting with a lot of things like solar panel, underground tunnel and space. Honda need to step up their research and development for space. they have the precision to manufacture things reliable. honda pefected Vtec. they didnt invent it they brought it and make it work. they were the first to make luxury car in north america but it fail. toyota knew how to make a real luxury interior and it was a success. honda tried to keep cost down when it comes to interior thats the reason why their luxury brand didnt win. most of their line up all shared components. look at the new NSX. it wasnt really exclusive to nsx. the entertainment is the same like others. although, nsx made other car model appealing but it will just make nsx not win in profit. that goes for luxury model.
Don't say its boring, I have watched so many of your videos since I found your channel and they are some of the best on you tube. Respect to the amount of work, knowledge and research that goes into them because you are definitely one of the best teachers on the web.
I graduated this year. There were 4 of us in project group. As our last year project we decided to fabricate a self-balancing mono-wheeler which tries to balance itself with help of a heavy mechanical gyroscope. For the reason of low budget we fabricated the whole chassis out of scrap and the gyroscope by stacking up heavy metal flanges to one single metal plate. Manufactured whichever part is required on Lathe machine. Despite there being advanced electronically self balanced mono-wheelers available in market already, we tried to reinvent the wheel like Honda did back then, just because we thought we would get to explore more about Physics. Neither of us had any experience of building an automobile whatsoever. Dealt with various difficulties like mitigating tremendous vibrations generated by flywheel at high RPM, improper alignments of parts because of not having access to precise machining and equipments, etc. After facing a lot of problems we fabricated it successfully but by doing so we left with very low time for it's testing. We ran out of time and the project got failed. We implemented free precession of gyroscope for this to accomplish and I do have an intuition that if forced precession method is used then perhaps this might become successful. Anyways, even though this wasn't a success I learnt very intricate topics of Mechanical engineering, learnt how to come up with tactical solutions under time trouble which I think will definitely help me out in the future. And most importantly I learnt your saying that "Failure is not opposite of success, if we learn from our mistakes" because I believe that maniacal things like these give birth to creativity.
@@ElSe1904 low emissions, way better fuel economy, and way more horsepower. Snowmobiles uses them all the time and with only a 850cc inline twin they can make 165 horsepower naturally aspirated, some manufacturers are now using turbos and upping it to 180, but that number stays that high all the way up to 8000 feet (used for mountain riding.) Where it takes a 900+cc four stroke inline 3 with a turbo to make even competitive horsepower at 180. And weighs even more for only 15 more horsepower than the NA two stroke, plus ends up burning more fuel than the two stroke anyway.
@@ElSe1904 becouse di 2 stroke baisically makes scavenging and exhaust pressure calculation redundant i'd imagine therefore opening up new potential for said firing cycle.
@@MaxHohenstaufen the area of a cilinder is basicly like a flat surface where you only heave one constraint on flatness, with the other 3 dimensional figures you basicly stack multiple flat surface together wich when machined might not have the exact dimensions per surface. single measurement of prescision beats mutliple measurements of precision
Love the video! One other thing the NR500 had was a needle bearing crankshaft to help lower power loss at high rpm. The NR750 had plain bearings as they’re much cheaper, more reliable and there was less of a need for needle bearings due to the lower redline of ‘only’ 14,000 rpm haha. If you ever go to Japan you can see both crankshafts for each engine on display in Honda’s museum.
I've wondered about plain vs needle. KTM switched from needle to plain bearings on their 4 stroke MX bikes sometime around 2012/2013. Their time between overhaul increased (per KTM spec), but in practice, both are exceptionally reliable. There must be other reasons for needle bearings other than high RPM? The KTM 500s for instance max at around 10k.
@@motominded5275 A roller bearing big end is generally lighter than a 2 piece bolted together split cap conrod and shells. The roller assembly also does not require a pressure fed pumped lube system
@@motominded5275 Absolutely. Kevin Cameron (CycleWorld)is very good on this. Roller bearings can survive on very little oil, whereas plain bearings will bind etc when air is supplied instead of oil; but the other side is that with well supplied oil, plain bearings last much longer under higher loads etc. And this is largely why you'll see motorbikes nowadays with plain bearings and deep sumps with a very deep collector going into them so that the engine still supplies lots of oil at persistently high lean angles.
@@villiamo3861 Thanks - so maybe the rollers are a hold-over "old world" tech when oiling systems were not what they are today. I've been curious about that. With KTM's switch ~10 years ago they upped the service intervals from sub 100 hrs to upwards of 150, I guess they are confident over the years of fine tuning the oil systems on the bikes....
Glad to see your videos back after a few months off. I really love your stuff. Very thoughtful. You explain things really well for me. Thanks for all your work to make these videos for the gear head community. 🙂
@@d4a A week without a d4a video is clearly like 3 months for lesser RUclipsrs. ;-) I can say that the channel on my Apple TV hasn't been updated for much more than a week. Likely some sort of setting on my side. Now I get to go find all the goodies I missed.
I'm purposely going to be quite vague, but I was with HONDA, during this time, ie late 70 thru 80z. The NR had many " aspects " working against the design, which I won't elaborate on. That being said, what I will discuss is the difficulty in the machining, and final precision Honing of the cylinders. The piston ring dilemma was solved reasonably well, but the cylinder finish, and sizing, not so much. Even with today's C.N.C. capabilities, it's simply not practical and border line, unachievable. The same " theory " can be said for the concept of oval valves. Benefits of the design, absolutely, yet not even remotely practical from a machining, and final outcome standpoint. Excellent job with the video. T.S. RACING
Actually struggling with the same issues in manufacturing in my job just different. One of the solutions is mass production of a product and then matching sizes based on tolerance variance fit. This only work in high volume though.
What amazed me was how they refused to even produce two stoke bikes to race while working on their oval engine. Maybe thinking that the racing group was there to support the production group. The Kawasaki two stroke street bikes were animals.
@Retired Bore it's why Honda got out of F1 racing is a waste of time and money for companies 9/10 times. It is purely just marketing. And more and more people are realizing that and marketing budgets are kind of just a waste in a lot of situations. Not to say these racing companies don't produce some spin off but it's rarely seen in production quickly these are usually technologies that don't get implemented till decades later.
As an engineer (I presume), you know that there are ways of doing things that are simply wrong. Putting a space between a quotation mark and the word or sentence being quoted, for example. Like "this" is right, and like " this " is wrong.
You missed the oval piston endurance racer of 88-89. It had a nearly flat torque curve from about 8000-15,000 rpm and was made over 150hp in 750cc endurance trim. It only raced in a couple of races at the end of the season, and still needed development work to win, but it was so much faster than the existing 750 4 strokes that the FIM banned it for the following season. The 500 was a "failure" but Honda figured out how to make it work. The did a ton of development work between 83 and 88 on a 250cc turbo charged oval piston test engine, that led to the 750cc endurance racer engine.
Yes - this racing 750 is really why the NR750 road bike could come out in the 90s (I actually thought it was 91 that the road bike came out, but may be wrong) - ie the 750 racer in the late 80s maintained interest in the design that had otherwise gone out of view in the early 80s; and I think that the 750 racer ran, and looked very impressive at, Suzuka?
Soichiro san was incredibly crazy enthusiast who went beyond share price and market shit and focussed on perfecting motorcycle tech. They don't make them like this any more
Honda's engineering is very underrated imo. They are like the Seiko of the car world. Thank you for the cool video, glad to see you working hard to bring quality content!
I have never thought Honda's prowess in the engineering field lacking. Those that think so simply don't know much about them. It's nice to see Honda collaborating with another pioneering company (Sony) in bringing more vehicles to market. To me, how cool is that, to see a Sony badge on modern electric vehicles?
@@rusack7174 their moped bodyworks are notoriously bad here, i could confirm since i got 3 of them, they tend to rattle after a while, even if you fix it they keep coming back like a roach. maybe because its designed by sub company's apprentice engineer, disassembling it feels like peeling a union. they got really good fuel economy though
@@rusack7174 they spread around southeast Asia with different name, mine was Honda absolute revo (2010), honda kharisma 125 (2007), honda vario 150 (2019). idk who design them since other sub company in other asian country sold "simillar but not the same" model, but i believe the one i had are produced by Astra Honda Motor which is affiliate? licensor? idk if you could call them sub company since honda own half their share.
Dad had a saying; 'don't be scared of failure, you learn bugger all from success, it's from your failures you really learn'. It's not a saying I repeat a lot, as it tends to get a lot of blank looks, but it's always one I keep in mind. In my own experience success all to often just ends up reinforcing bad habits.
What a concept? taking a failure and making a success out of it. which also allowed Honda to thumb their noses up at their sceptics. you have hand it to the Japanese for being so bold.
As an engineer (electrical/computer), I absolutely love this story! Thank you for yet another fascinating and captivating video, presented in your always-engaging style!
This was the essence of Honda and where legions of Honda faithful worshipped. That pioneering spirit, tempered somewhat from the realities of today, can still be seen today in various products they manufacture. Like myself, those growing up in those early years of Honda the giant killer would like to see more of that.
I want a video on sleeve valves! I feel like a sleeve valve engine for a dirt bike would be a potential winner. Emissions are not an issue for off-road racing use vehicles (see 2T dirt bikes), potential for better breathing than a poppet valve engine, more compact engine, lighter?, potential to rev higher...
If life was fare only Honda would be building cars, ordinary ones go to scrap yard with all original major components , older type ones not modern c rap
I was failing multiple times in my programming project, it was extremely painful mentally and I even do self harm just because how disappointed I am towards myself. but after watching this vid knowing what honda did, i can't imagine how much mental pain those engineers felt. they kept going and going even though they still failed to win, he has said a powerful statement to me who's cursed with pessimism and perfectionism. I now realised the most valuable thing is not succeeding but improve, I forgot how much i improved and the fact that i did improved without relying tutorial (what I'm trying to make is extremely uncommon for a tutorial) should be seen as an achievement for me instead of comparing myself with someone else that have vastly more experience and knowledge than me and be absolutely disappointed by it. my mind keep resisting but my body accepting it, so much so i shed a bit of tear at the last section of the vid. feel the pain of progress and keep on moving forward.
Failure is definitely part of the the learning process with software development. It is very common for complexity to get out of hand, making the project become impossible, no matter how hard you work at it. After a few failures like that, you start thinking at a strategic level. You start thinking about how you can minimize and manage the complexity right from the start. And that's when you become a good software developer.
Thank you for pointing out that failure is often the precursor to success with perseverance. When you first said to not go against normal construction it took me off guard coming from you. Loved the way you presented this!
I don't put too many comments on videos but I did comment on one your previous ones and asked if you would produce something on the Oval Piston engine. Now, I am sure I am not the only one who asked but I knew it would be facinating, your presentation and delivery style has made it even better. Thank you for taking the time to make this and for those who knew nothing or little about this feat of engineering I am sure they now much better educated as indeed I am and remember the engine in its day....every day is a school day
Just like Churchill said: Success is not final, failure is not fatal: it is the courage to continue that counts' - Believe In Yourself and Never Give In.
I mean, maybe he could've mentioned it, but those things aren't self-propelling and don't have to rev to the moon in order to be effective so it's not really an apples to apples comparison.
Do remember that pumps are a lot more flexible about what kind of impeller design they use. Steady state, generally more lax about a little bit of leakage. Wankel rotaries are sometimes used for seatbelt retractors, for example.
@@Appletank8 "Wankel rotaries are sometimes used for seatbelt retractors" Can you cite an example application for those of us who live under rocks. Thanks.
I was standing on the first corner at Silverstone and remember the day well. The NR had other issues as well, over heating and the chassis in general. They eventually put the engine in a Ron William (Maxton) frame but it still wasn't competitive even in the hands of Freddie Spencer. There were so many issues the NR came to stand for 'nearly ready'. Enter the NS and NSR 500s. Good video.
Some marine two stroke diesel engines had oval pistons in the 70s and 80s. My father was on a ship where the oval piston engine was removed because it was not reliable and a more conventional round piston engine was installed. (Ships engines run for millions of hours, so reliability is everything) He cannot remember the engine manufactures.
Bravo - well said! Important history, and very amusing example of 'creative interpretation of the rules', by a truly great engineering company. I remember this whole affair (being really old), and yet I learned something here - I had no idea that the NR750 streetbike had pistons that were actually oval! I always assumed that it had the same flat-sided pistons as the racebike... Thanks!
I think that further investigation should go into your conclusion. I can not speak for this specific instance, but sometimes attempting to reinvent the wheel is what moves us from using the wheel to using tracks, which moves us to the next great innovation. Alot lot of great innovations come at the cost of failed innovation attempts.
Great video as usual, thanks! I was getting worried as you were getting closer to the conclusion that it was a total failure, but breathed a sigh of relief as I got past it. Don't care if it didn't make any sense, just loved that they took on the challenge and loved the NR (road version), it was my dream bike as a teenager. And it was indeed the source of so many groundbreaking innovations---you didn't mention that it was the first bike with a swing arm suspension and the exhaust coming out of the back of the seat, so cool for the time! But guess that's not engine related so you're forgiven 😊
Honda were limited to four cylinders by racing regulations. The NR was an V8 wearing four cylinders. It frightened the competition to death as they couldn't afford the tooling. The Moto Guzzi V8 500 cc of the 1950's achieved 180 mph.
Great video! It shows how much context is sometimes necessary to shine light on the reasons why a company develops a certain product. You're very correct if it comes to failure and learning from it. Unfortunately, it doesn't ease my fear of failure that is underlined during my ongoing graduation as an electric engineer. We all have our hurdles in life, I guess. That's why respect the determination that Honda showed that much more as well as their sass of releasing a limit amount of the bike that carried the engine predicted by everyone to would fail.
I was around, and had several Honda Sportbikes in my garage, when the 750 NR Oval Piston came out..... And we knew then, what you are telling us now... That it didn't work that great, it was super complicated, and all that.... But I can tell you, we ALL WANTED ONE. Everyone. To this day, when I see them for sale, I am deeply deeply tempted.....
Very well explained. Thanks!! I remember reading about the project in Cycle World way back in the last century when I was young. I remember explaining it to my father and uncle and they said "why?" ...so I explained why and they said "it'll never work"
Honda changed to two-stroke world in 1974 with the release of the Honda CR125M and 250 Elsinores. They changed the off road motocrsycle world forever. The 1974 CR125M was produced in greater numbers than any motocross bike ever built. It introduced a generation of riders to racing and, more than any other single motorcycle, was responsible for the dirt bike boom that followed. It’s impossible to overstate the impact of that one motorcycle on the sport we know today.
A few years ago, I met an elderly man who formerly worked for Douglas Aircraft. Honda of Japan approached Douglas Aircraft to build some carbon composite frames, swing arms and wheels for this vary project. All these years later, he never heard any details regarding the parts he built for Honda. As fate would have it, a former employee of mine was heading up American Honda racing. I asked him if there was any way to get some info regarding this project, for my engineering friend. Months later, a package arrived at my place direct from Japan, magazines with full stories about the NR's development. Needless to say I made one old man very happy. We had dinner and he insisted to go to Kinko's to print me copies of his black and white photos of his records of the carbon parts he made all those years ago. Amazing
I remember those Honda F1 bikes. The NR500 was a great idea and if any company could make it work Honda could. I was a Kenny Roberts/Yamaha fan, but Honda just amazed me with stuff like this. They eventually made V4 engines for the streets and I had one. That VF500 was the coolest little bike ever.
'King Kenny' led a progression of American born Moto GP champions, IIRC followed by Freddie Spenser, Eddie Lawson, Wayne Rainey, and more ( I stopped following Moto GP much after that). At the time, it was rumored that the American's growinig up racing on dirt, was a significant advantage as the leading racers were perfecting sliding the motorcycle tires on pavement. Watching Moto GP back then was an incredibly exciting spectator sport, and it was amazing at how many riders survived what we thought should have been fatal accidents. I rode a Honda all through those years. The CBX and then a couple of Gold Wings brought me around the country many times.
I love your videos. So informative and even, in the case of today, philosophical. I really appreciated your take on failure. We can all learn so much from failure. Fail big and fail often, you will eventually achieve success that no one else thought possible.
I suspect there is a bit missing to this marvalous video. If Homda are tenacious enough to pursue oval pistons then they must have realised that a big oval inlet valve and big oval exhaust valve would be double the gasflow area than 2 rows each of 4 round conventional valves. So what is the story on the valves? It was interesting when your video showed Honda making the valves larger & larger until the seats were overlapping. You said they could increase bore size. You said that would increase cc. But thats a bonus. Because increasing bore size = increased cc and Decreasing stroke would restore cc to spec with the advantage of increasing the potential upper RPM limit. Please make a pt 2 to this great video. Thanks.
Excellent video. Clear, accurate comparison of 2-stroke and 4-stroke engines. Nevertheless, here's my tip for speakers and writers: we should use big words only when small words won't work as well. That's why I think the 4 strokes of a 4-stroke engine may be more precisely, more eloquently, more graphically, and better described as being the sucking, squeezing, banging, and blowing strokes rather than intake, compression, power, and exhaust strokes. And these gerunds, ing-words, noun forms of verbs, have the verb forms that they were derived from, action words - suck, squeeze, bang, blow - to describe what's going on in each cylinder. For 3 of the "big-word" nouns such as intake, compression, power, and exhaust, we have verb forms that are identical to or based upon their noun form: intake (or take in), compress, and exhaust. But for the _power_ stroke, the verb _power_ doesn't seen to work quite so well here. It is not as descriptive, not as graphic, as one might like. You _can_ _power_ something but what happens during a power stroke is not merely _powering_ Rather, it is _combustion of the mixture of fuel and air, resulting in rapid heating and rapid expansion of combustion gasses due to the heat - expansion so rapid that it could almost be thought of, felt as, or heard as - an explosion. _*_Bang._*_ It may not actually be an explosion but confined to a cylinder the sound it makes is a _bang._ Parallel structure communicates best. That's why I say Intake, compress, bang, exhaust. What more graphically and more eloquently describes stroke number three than *bang? Bang, bang, bang.* At every third stroke of each cylinder, the substances inside go *bang.* The third stroke is the *bang* stroke. Suck squeeze bang blow. Intake, compress, bang, exhaust.
@D4A - If all the NR was, in essence, a work-around for displacement(air volume), then why not forced induction? And I agree - there's no such thing as failure, if and only if, you learn from said "failure". So, in summation, the NR pushed Honda to relearn Alloy and Machining technologies...?
@@d4a Sidebar/Unrelated - Could you do a vlog on Mazda's "Compression Ignition" engine? I mean, wouldn't that involve a whole new way of thinking about knocking? And if you've already done one - post the link?
@@d4a Interestingly (at least to me!) I think it had been allowed in the 30s (in GP racing, but before the whole World Championships started in the 50s), and this is why you can see impressively fast BMW twins etc of that era - but then, as you say, it was ruled out: otherwise the two strokes could have also taken advantage of it just as well as the four strokes - most of the world's shipping is carried, I believe, by supercharged diesel two strokes.
Just wanted to say thank you for making such interesting videos and the high quality subtitles. I’m almost completely deaf and don’t have hearing aids, and RUclips’s auto generated subtitles are hot garbage.
Great video and thanks for reminding me of those days. In the 80’s I was a big Yamaha fan and loved my 2-stroke RZ 350 and 500 bikes but was amazed at the tenacity (I probably called it something else back then) of Honda to push 4-stroke engineering in the NR. Honda applied different ideas when developing the NS, the production NS400R Grand Prix replica was very different from its competitors (RZ500 and RG500). When the production NR finally came out it looked like a possible sport bike future that of course never came to be.
When I was in grad school I read the sae technical paper honda published on the nr development. The oval piston shape derived from practical limits on bore to stroke ratio & max piston speed which indicated they needed a v8 to make the horsepower. Since rules said max of 4 cylinders they "siamesed" pairs of cylinders. The 8 valves were a fortuitous side effect.
Nice video, it’s refreshing to see someone cover the NR story from a different perspective. As someone who studied in substantial detail the overall story, achievements and failures, I can say that there are way more anecdotes and milestones that are worth sharing. Perhaps at some point I will make a video on this topic too 🙂
In 1981 I was working with a group at Sears Point Raceway where we were trying to clad the cylinder wall of the oval pistons with a ceramic material. The idea was to increase the combustion temps for more power while providing better wear characteristics with synthetic oils. Machining was just to difficult at that time, mostly due to the material need to be ground versus other methods because it was so hard.
I am so impressed with your presentation that I subscribed half of the way through this video. The first of yours that I have seen. Keep up the good work, KID!
I'm not sure which impresses me more, Honda's vision and persistence or the research you did in order to present this video - in any case thank you very much and I have to say your style is excellent and you speak very clearly, looking forward to watching more of your videos and of course I just subscribed.
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see aptera owners club video on saftey, heavy cars make it less safe for lighter cars but heavier doesnt totally mean safer, and join the disc ord server in the description box under the video, my name there is animate mental terrorism
Do Britton motorcycles next.
You can increase bore and not raise displacement by reducing stroke. Proof of Honda doing this in reverse is the difference in The SC 57 Vs SC 59 CBR 1000rr.
Why don't they make the valves in a oval chape?
I've always liked companies that dare to experiment. And Soichiro Honda is a legend.
me too. just like when google first emerge, they do things differently. they made a lot of freebies for internet user. they were trying to experiment with a lot of internet things. i remember we talk a while back saying, eventually you see big companies go to space once they have the capital to do so. i remember saying, honda is one of them as they are a very stable company and they do a lot of research and development of new tech just like asimo. now you have blue orgin and space X. elon musk, is experimenting with a lot of things like solar panel, underground tunnel and space. Honda need to step up their research and development for space. they have the precision to manufacture things reliable.
honda pefected Vtec. they didnt invent it they brought it and make it work. they were the first to make luxury car in north america but it fail. toyota knew how to make a real luxury interior and it was a success. honda tried to keep cost down when it comes to interior thats the reason why their luxury brand didnt win. most of their line up all shared components. look at the new NSX. it wasnt really exclusive to nsx. the entertainment is the same like others. although, nsx made other car model appealing but it will just make nsx not win in profit. that goes for luxury model.
100%
Stock holders don’t like it. They want to not lose money.
When he was a child, he seemed to lick oil and compare the taste.
Amen
Don't say its boring, I have watched so many of your videos since I found your channel and they are some of the best on you tube. Respect to the amount of work, knowledge and research that goes into them because you are definitely one of the best teachers on the web.
Thank you so much
It's everything BUT boring!
Greetings from the Netherlands
Yeah, I agree, nothing boring here, your videos are verrrrrry accurate, easy to understand and entertaining at the same time, thanks for your work!!
"Boring" often is a short-form for "really interesting!".
I graduated this year. There were 4 of us in project group. As our last year project we decided to fabricate a self-balancing mono-wheeler which tries to balance itself with help of a heavy mechanical gyroscope. For the reason of low budget we fabricated the whole chassis out of scrap and the gyroscope by stacking up heavy metal flanges to one single metal plate. Manufactured whichever part is required on Lathe machine. Despite there being advanced electronically self balanced mono-wheelers available in market already, we tried to reinvent the wheel like Honda did back then, just because we thought we would get to explore more about Physics. Neither of us had any experience of building an automobile whatsoever. Dealt with various difficulties like mitigating tremendous vibrations generated by flywheel at high RPM, improper alignments of parts because of not having access to precise machining and equipments, etc. After facing a lot of problems we fabricated it successfully but by doing so we left with very low time for it's testing. We ran out of time and the project got failed. We implemented free precession of gyroscope for this to accomplish and I do have an intuition that if forced precession method is used then perhaps this might become successful.
Anyways, even though this wasn't a success I learnt very intricate topics of Mechanical engineering, learnt how to come up with tactical solutions under time trouble which I think will definitely help me out in the future. And most importantly I learnt your saying that "Failure is not opposite of success, if we learn from our mistakes" because I believe that maniacal things like these give birth to creativity.
You LEARNED a lot.
And you would perfect working on NASA contracts, as they seem to, ah, always, go over time and budget, he-he.
@@raynic1173 yeah with engineers who graduate near the top of their class.
Dunce.
@@touristguy87 Ah, I worked on NASA contracts with NASA engineers, so dunce what? Please explain?
@@raynic1173 you're not even unpaid intern material...maybe a tech for a 2nd level contractor
i have too respect Honda’s imagination, could you please talk about 2 stroke direct injection engine and opposed piston engine please?
What is so interesting about the 2 stroke DI engine? Opposed piston sounds interesting but the 2 stroke...not so much
@@ElSe1904 opposed engines works in two stroke principal
@@farukgulluce8601 He asked for explanation of 2 stroke AND opposed piston engines... Thats why i pointed it out
@@ElSe1904 low emissions, way better fuel economy, and way more horsepower. Snowmobiles uses them all the time and with only a 850cc inline twin they can make 165 horsepower naturally aspirated, some manufacturers are now using turbos and upping it to 180, but that number stays that high all the way up to 8000 feet (used for mountain riding.) Where it takes a 900+cc four stroke inline 3 with a turbo to make even competitive horsepower at 180. And weighs even more for only 15 more horsepower than the NA two stroke, plus ends up burning more fuel than the two stroke anyway.
@@ElSe1904 becouse di 2 stroke baisically makes scavenging and exhaust pressure calculation redundant i'd imagine therefore opening up new potential for said firing cycle.
A circle also has the smallest area of contact vs the total area to seal off.
And it is homogenous, whereas angled shapes have points of stress peak, which is problematic if we're talking about sealing preassure.
@@MaxHohenstaufen the area of a cilinder is basicly like a flat surface where you only heave one constraint on flatness, with the other 3 dimensional figures you basicly stack multiple flat surface together wich when machined might not have the exact dimensions per surface. single measurement of prescision beats mutliple measurements of precision
Love the video! One other thing the NR500 had was a needle bearing crankshaft to help lower power loss at high rpm. The NR750 had plain bearings as they’re much cheaper, more reliable and there was less of a need for needle bearings due to the lower redline of ‘only’ 14,000 rpm haha. If you ever go to Japan you can see both crankshafts for each engine on display in Honda’s museum.
I've wondered about plain vs needle. KTM switched from needle to plain bearings on their 4 stroke MX bikes sometime around 2012/2013. Their time between overhaul increased (per KTM spec), but in practice, both are exceptionally reliable. There must be other reasons for needle bearings other than high RPM? The KTM 500s for instance max at around 10k.
@@motominded5275 A roller bearing big end is generally lighter than a 2 piece bolted together split cap conrod and shells. The roller assembly also does not require a pressure fed pumped lube system
@@howardosborne8647 thanks.....so maybe roller bearings are more immune to poor oiling systems / failures?
@@motominded5275 Absolutely. Kevin Cameron (CycleWorld)is very good on this. Roller bearings can survive on very little oil, whereas plain bearings will bind etc when air is supplied instead of oil; but the other side is that with well supplied oil, plain bearings last much longer under higher loads etc.
And this is largely why you'll see motorbikes nowadays with plain bearings and deep sumps with a very deep collector going into them so that the engine still supplies lots of oil at persistently high lean angles.
@@villiamo3861 Thanks - so maybe the rollers are a hold-over "old world" tech when oiling systems were not what they are today. I've been curious about that. With KTM's switch ~10 years ago they upped the service intervals from sub 100 hrs to upwards of 150, I guess they are confident over the years of fine tuning the oil systems on the bikes....
I appreciate how much research you did to put up this amazing episode.
Glad to see your videos back after a few months off. I really love your stuff. Very thoughtful. You explain things really well for me. Thanks for all your work to make these videos for the gear head community. 🙂
There was only one week without a video 😧
@@d4a felt like longer 🤣
@@d4a A week without a d4a video is clearly like 3 months for lesser RUclipsrs. ;-) I can say that the channel on my Apple TV hasn't been updated for much more than a week. Likely some sort of setting on my side. Now I get to go find all the goodies I missed.
You’ve said it all, I’ve nothing to add
I'm purposely going to be quite vague, but I was with HONDA, during this time, ie late 70 thru 80z.
The NR had many
" aspects " working against the design, which I won't elaborate on. That being said, what I will discuss is the difficulty in the machining, and final precision Honing of the cylinders. The piston ring dilemma was solved reasonably well, but the cylinder finish, and sizing, not so much. Even with today's C.N.C. capabilities, it's simply not practical and border line, unachievable. The same " theory " can be said for the concept of oval valves. Benefits of the design, absolutely, yet not even remotely practical from a machining, and final outcome standpoint.
Excellent job with the video.
T.S. RACING
@Retired Bore companies would rather chase money sadly.
Actually struggling with the same issues in manufacturing in my job just different. One of the solutions is mass production of a product and then matching sizes based on tolerance variance fit. This only work in high volume though.
What amazed me was how they refused to even produce two stoke bikes to race while working on their oval engine. Maybe thinking that the racing group was there to support the production group. The Kawasaki two stroke street bikes were animals.
@Retired Bore it's why Honda got out of F1 racing is a waste of time and money for companies 9/10 times. It is purely just marketing.
And more and more people are realizing that and marketing budgets are kind of just a waste in a lot of situations.
Not to say these racing companies don't produce some spin off but it's rarely seen in production quickly these are usually technologies that don't get implemented till decades later.
As an engineer (I presume), you know that there are ways of doing things that are simply wrong. Putting a space between a quotation mark and the word or sentence being quoted, for example. Like "this" is right, and like " this " is wrong.
You missed the oval piston endurance racer of 88-89. It had a nearly flat torque curve from about 8000-15,000 rpm and was made over 150hp in 750cc endurance trim. It only raced in a couple of races at the end of the season, and still needed development work to win, but it was so much faster than the existing 750 4 strokes that the FIM banned it for the following season. The 500 was a "failure" but Honda figured out how to make it work. The did a ton of development work between 83 and 88 on a 250cc turbo charged oval piston test engine, that led to the 750cc endurance racer engine.
Yes - this racing 750 is really why the NR750 road bike could come out in the 90s (I actually thought it was 91 that the road bike came out, but may be wrong) - ie the 750 racer in the late 80s maintained interest in the design that had otherwise gone out of view in the early 80s; and I think that the 750 racer ran, and looked very impressive at, Suzuka?
Yes, Suzuka..i thought I was mis remembering the nr750..edit: leman 24, in 87 and it was a rocket. Not suzuka..
Soichiro san was incredibly crazy enthusiast who went beyond share price and market shit and focussed on perfecting motorcycle tech. They don't make them like this any more
God that 250cc's I6's exhaust note. Gorgeous.
This is probably the best video I've seen on RUclips on Honda's oval cylinder. Great job.
I'm falling deeper and deeper in love with this channel the more motorcycle content it produces
Honda's engineering is very underrated imo. They are like the Seiko of the car world. Thank you for the cool video, glad to see you working hard to bring quality content!
Everyone talks German engineering because of the complexity, while Japanese engineering is about simplicity or well something like that
I have never thought Honda's prowess in the engineering field lacking. Those that think so simply don't know much about them. It's nice to see Honda collaborating with another pioneering company (Sony) in bringing more vehicles to market. To me, how cool is that, to see a Sony badge on modern electric vehicles?
@@rusack7174 their moped bodyworks are notoriously bad here, i could confirm since i got 3 of them, they tend to rattle after a while, even if you fix it they keep coming back like a roach. maybe because its designed by sub company's apprentice engineer, disassembling it feels like peeling a union. they got really good fuel economy though
@@mr.2minutes161 Where's "here" and what model moped are you talking about?
@@rusack7174 they spread around southeast Asia with different name, mine was Honda absolute revo (2010), honda kharisma 125 (2007), honda vario 150 (2019). idk who design them since other sub company in other asian country sold "simillar but not the same" model, but i believe the one i had are produced by Astra Honda Motor which is affiliate? licensor? idk if you could call them sub company since honda own half their share.
You're the best on RUclips, I wish you could do more installments...I know it's a lot of work but it is truly quality material that is a joy to watch😊
Asking a question right before an advertisment is such a smart move, makes you not skip it
Dad had a saying; 'don't be scared of failure, you learn bugger all from success, it's from your failures you really learn'. It's not a saying I repeat a lot, as it tends to get a lot of blank looks, but it's always one I keep in mind. In my own experience success all to often just ends up reinforcing bad habits.
I've just come from a recent failure in my life, and somehow this video lifts me up.
What a concept? taking a failure and making a success out of it. which also allowed Honda to thumb their noses up at their sceptics. you have hand it to the Japanese for being so bold.
Wow! This is the very first time I'm understanding deeply the difference between a two-stroke and four-stroke cycle. Thanks
As an engineer (electrical/computer), I absolutely love this story! Thank you for yet another fascinating and captivating video, presented in your always-engaging style!
I live near the Barber Motorsports Museum in Alabama and they have an NR750 in their collection. It’s a beautiful machine.
I love the feeling of seeing D4A in the subscriptions feed with a new video. Amazing quality!
This was the essence of Honda and where legions of Honda faithful worshipped. That pioneering spirit, tempered somewhat from the realities of today, can still be seen today in various products they manufacture. Like myself, those growing up in those early years of Honda the giant killer would like to see more of that.
Good video explaining the design of the engine and the lessons Honda learnt through building it.
I want a video on sleeve valves! I feel like a sleeve valve engine for a dirt bike would be a potential winner. Emissions are not an issue for off-road racing use vehicles (see 2T dirt bikes), potential for better breathing than a poppet valve engine, more compact engine, lighter?, potential to rev higher...
NONE of your videos are boring! Thank you for your work!
Thanks a lot for continuing to create high-quality videos, and kudos to whoever taught you English, as it’s so pleasant to listen to.
16:26 "Failure is not a complete opposite of success" -D4A 2022
Your V5 vs V4 Engine Video is anything than boring! I learned so much from it and all of your other videos
I'm not sure there's another channel on RUclips that combines explanations of technical issues with motivational speaking and life lessons.
Honda is one of my favorite companies. Thank you for such a historical perspective in addition to the technical. This was enjoyable to watch.
If life was fare only Honda would be building cars, ordinary ones go to scrap yard with all original major components , older type ones not modern c rap
I've been anticipating you covering this, i thought it was going to be an iconic engines video like the 6 valve. But this is still very cool!
Fantastic video - probably the best I've seen on the subject.
Boy do I carry the valuable experiences of many many failures under my belt. ;) Excellent video!
I was failing multiple times in my programming project, it was extremely painful mentally and I even do self harm just because how disappointed I am towards myself. but after watching this vid knowing what honda did, i can't imagine how much mental pain those engineers felt. they kept going and going even though they still failed to win, he
has said a powerful statement to me who's cursed with pessimism and perfectionism. I now realised the most valuable thing is not succeeding but improve, I forgot how much i improved and the fact that i did improved without relying tutorial (what I'm trying to make is extremely uncommon for a tutorial) should be seen as an achievement for me instead of comparing myself with someone else that have vastly more experience and knowledge than me and be absolutely disappointed by it. my mind keep resisting but my body accepting it, so much so i shed a bit of tear at the last section of the vid. feel the pain of progress and keep on moving forward.
Failure is definitely part of the the learning process with software development. It is very common for complexity to get out of hand, making the project become impossible, no matter how hard you work at it. After a few failures like that, you start thinking at a strategic level. You start thinking about how you can minimize and manage the complexity right from the start. And that's when you become a good software developer.
Thank you for pointing out that failure is often the precursor to success with perseverance. When you first said to not go against normal construction it took me off guard coming from you. Loved the way you presented this!
Great Video! By the way, the vid about the V5 engine was one of the most interesting you have made!
Excellent presentation. I remember when that bike first came out. Everyone was scratching their heads wondering what to make of it.
I don't put too many comments on videos but I did comment on one your previous ones and asked if you would produce something on the Oval Piston engine.
Now, I am sure I am not the only one who asked but I knew it would be facinating, your presentation and delivery style has made it even better.
Thank you for taking the time to make this and for those who knew nothing or little about this feat of engineering I am sure they now much better educated as indeed I am and remember the engine in its day....every day is a school day
Quality video as allways. Have a Nice evening. Looking forward to see the next video.
Just like Churchill said: Success is not final, failure is not fatal: it is the courage to continue that counts' - Believe In Yourself and Never Give In.
The oval piston is sort of in the industry world wide. It's widely used in compressors for refrigeration systems.
@J M yeah donut is quite inaccurate on some stuff
@@johnhunter7244 donut is an entertainment channel, while d4a is an educational channel, in most cases
I mean, maybe he could've mentioned it, but those things aren't self-propelling and don't have to rev to the moon in order to be effective so it's not really an apples to apples comparison.
Do remember that pumps are a lot more flexible about what kind of impeller design they use. Steady state, generally more lax about a little bit of leakage. Wankel rotaries are sometimes used for seatbelt retractors, for example.
@@Appletank8 "Wankel rotaries are sometimes used for seatbelt retractors" Can you cite an example application for those of us who live under rocks. Thanks.
This is the best Engine science technology channel on yt period!
Be proud bro you explain things excellent and clear and nowadays that's rear!
Excellent presentation!! Thank you for your time, perseverance and research 🧐
I was standing on the first corner at Silverstone and remember the day well. The NR had other issues as well, over heating and the chassis in general. They eventually put the engine in a Ron William (Maxton) frame but it still wasn't competitive even in the hands of Freddie Spencer. There were so many issues the NR came to stand for 'nearly ready'. Enter the NS and NSR 500s. Good video.
Some marine two stroke diesel engines had oval pistons in the 70s and 80s. My father was on a ship where the oval piston engine was removed because it was not reliable and a more conventional round piston engine was installed. (Ships engines run for millions of hours, so reliability is everything) He cannot remember the engine manufactures.
WOW, this is as nerdy as it gets. I've come to a point where life almost wouldn't make sense anymore without your videos. Just freakin' amazing...
I love so much how you explain things, it's so easy to understand! Thanks!
Bravo - well said! Important history, and very amusing example of 'creative interpretation of the rules', by a truly great engineering company. I remember this whole affair (being really old), and yet I learned something here - I had no idea that the NR750 streetbike had pistons that were actually oval! I always assumed that it had the same flat-sided pistons as the racebike... Thanks!
I think that further investigation should go into your conclusion. I can not speak for this specific instance, but sometimes attempting to reinvent the wheel is what moves us from using the wheel to using tracks, which moves us to the next great innovation. Alot lot of great innovations come at the cost of failed innovation attempts.
Great video as usual, thanks! I was getting worried as you were getting closer to the conclusion that it was a total failure, but breathed a sigh of relief as I got past it. Don't care if it didn't make any sense, just loved that they took on the challenge and loved the NR (road version), it was my dream bike as a teenager. And it was indeed the source of so many groundbreaking innovations---you didn't mention that it was the first bike with a swing arm suspension and the exhaust coming out of the back of the seat, so cool for the time! But guess that's not engine related so you're forgiven 😊
"Super boring", you say? Yah! That's why I like watching this channel so much!
Failure is one of the best teachers. If not the best! Thanks for another awesome video
Honda were limited to four cylinders by racing regulations.
The NR was an V8 wearing four cylinders.
It frightened the competition to death as they couldn't afford the tooling.
The Moto Guzzi V8 500 cc of the 1950's achieved 180 mph.
Great video! It shows how much context is sometimes necessary to shine light on the reasons why a company develops a certain product. You're very correct if it comes to failure and learning from it. Unfortunately, it doesn't ease my fear of failure that is underlined during my ongoing graduation as an electric engineer. We all have our hurdles in life, I guess. That's why respect the determination that Honda showed that much more as well as their sass of releasing a limit amount of the bike that carried the engine predicted by everyone to would fail.
Absolutely love your videos! Thank you for all of the research and how you present these subjects.
i cant imagine my life without D4A
I just CANNOT
Dude not only teaches me everything i know about engines but gives me good life advice while doing it
Interesting, informative, accurate, funny, well made. Thanks for all your research, I appreciate it very much!
Never boring mate 👍👍
Brilliant explanation as always 👌👌
Came here to learn about engines, now I also learned about life lessons. Good job Mr. RUclips man, keep it up!
You make some of the best car guy content ever bro. RESPECT!! Thanks for the great videos
I was around, and had several Honda Sportbikes in my garage, when the 750 NR Oval Piston came out.....
And we knew then, what you are telling us now... That it didn't work that great, it was super complicated, and all that....
But I can tell you, we ALL WANTED ONE. Everyone. To this day, when I see them for sale, I am deeply deeply tempted.....
And this is exactly why I've invested my millions in the triangular shaped piston.
Very well explained. Thanks!! I remember reading about the project in Cycle World way back in the last century when I was young. I remember explaining it to my father and uncle and they said "why?" ...so I explained why and they said "it'll never work"
Honda changed to two-stroke world in 1974 with the release of the Honda CR125M and 250 Elsinores. They changed the off road motocrsycle world forever. The 1974 CR125M was produced in greater numbers than any motocross bike ever built. It introduced a generation of riders to racing and, more than any other single motorcycle, was responsible for the dirt bike boom that followed. It’s impossible to overstate the impact of that one motorcycle on the sport we know today.
Excellent video with outstanding closing. Bravo!
A few years ago, I met an elderly man who formerly worked for Douglas Aircraft.
Honda of Japan approached Douglas Aircraft to build some carbon composite frames, swing arms and wheels for this vary project. All these years later, he never heard any details regarding the parts he built for Honda. As fate would have it, a former employee of mine was heading up American Honda racing. I asked him if there was any way to get some info regarding this project, for my engineering friend. Months later, a package arrived at my place direct from Japan, magazines with full stories about the NR's development. Needless to say I made one old man very happy. We had dinner and he insisted to go to Kinko's to print me copies of his black and white photos of his records of the carbon parts he made all those years ago. Amazing
What a story!!
@@d4a By the way...$100,000,000 per set.
I remember those Honda F1 bikes. The NR500 was a great idea and if any company could make it work Honda could.
I was a Kenny Roberts/Yamaha fan, but Honda just amazed me with stuff like this. They eventually made V4 engines for the streets and I had one. That VF500 was the coolest little bike ever.
'King Kenny' led a progression of American born Moto GP champions, IIRC followed by Freddie Spenser, Eddie Lawson, Wayne Rainey, and more ( I stopped following Moto GP much after that). At the time, it was rumored that the American's growinig up racing on dirt, was a significant advantage as the leading racers were perfecting sliding the motorcycle tires on pavement. Watching Moto GP back then was an incredibly exciting spectator sport, and it was amazing at how many riders survived what we thought should have been fatal accidents. I rode a Honda all through those years. The CBX and then a couple of Gold Wings brought me around the country many times.
I love your videos. So informative and even, in the case of today, philosophical. I really appreciated your take on failure. We can all learn so much from failure. Fail big and fail often, you will eventually achieve success that no one else thought possible.
wow, that street NR must be the prettiest R ever.
it really kept the italian thinking after that.
I suspect there is a bit missing to this marvalous video.
If Homda are tenacious enough to pursue oval pistons then they must have realised that a big oval inlet valve and big oval exhaust valve would be double the gasflow area than 2 rows each of 4 round conventional valves.
So what is the story on the valves?
It was interesting when your video showed Honda making the valves larger & larger until the seats were overlapping.
You said they could increase bore size.
You said that would increase cc.
But thats a bonus.
Because increasing bore size = increased cc and Decreasing stroke would restore cc to spec with the advantage of increasing the potential upper RPM limit.
Please make a pt 2 to this great video.
Thanks.
Excellent video. Clear, accurate comparison of 2-stroke and 4-stroke engines. Nevertheless, here's my tip for speakers and writers: we should use big words only when small words won't work as well. That's why I think the 4 strokes of a 4-stroke engine may be more precisely, more eloquently, more graphically, and better described as being the sucking, squeezing, banging, and blowing strokes rather than intake, compression, power, and exhaust strokes. And these gerunds, ing-words, noun forms of verbs, have the verb forms that they were derived from, action words - suck, squeeze, bang, blow - to describe what's going on in each cylinder. For 3 of the "big-word" nouns such as intake, compression, power, and exhaust, we have verb forms that are identical to or based upon their noun form: intake (or take in), compress, and exhaust. But for the _power_ stroke, the verb _power_ doesn't seen to work quite so well here. It is not as descriptive, not as graphic, as one might like. You _can_ _power_ something but what happens during a power stroke is not merely _powering_ Rather, it is _combustion of the mixture of fuel and air, resulting in rapid heating and rapid expansion of combustion gasses due to the heat - expansion so rapid that it could almost be thought of, felt as, or heard as - an explosion. _*_Bang._*_ It may not actually be an explosion but confined to a cylinder the sound it makes is a _bang._ Parallel structure communicates best. That's why I say Intake, compress, bang, exhaust. What more graphically and more eloquently describes stroke number three than *bang? Bang, bang, bang.* At every third stroke of each cylinder, the substances inside go *bang.* The third stroke is the *bang* stroke. Suck squeeze bang blow. Intake, compress, bang, exhaust.
That was just incredible! Thanks for the fascinating history lesson 👍👍
Great history and excellent job finding those videos of the oval piston engine insides!
wonderful video. thanks. I love anything motorcycle.
great video! i've seen other videos about the oval piston engine, but they didnt give that much attention to the company history
@D4A - If all the NR was, in essence, a work-around for displacement(air volume), then why not forced induction? And I agree - there's no such thing as failure, if and only if, you learn from said "failure". So, in summation, the NR pushed Honda to relearn Alloy and Machining technologies...?
Forced induction also wasn't allowed in the rules
Forced induction also wasn't allowed in the rules
@@d4a Sidebar/Unrelated - Could you do a vlog on Mazda's "Compression Ignition" engine? I mean, wouldn't that involve a whole new way of thinking about knocking? And if you've already done one - post the link?
@@d4a Interestingly (at least to me!) I think it had been allowed in the 30s (in GP racing, but before the whole World Championships started in the 50s), and this is why you can see impressively fast BMW twins etc of that era - but then, as you say, it was ruled out: otherwise the two strokes could have also taken advantage of it just as well as the four strokes - most of the world's shipping is carried, I believe, by supercharged diesel two strokes.
Hard not to respect hondas amazing engineering
Just wanted to say thank you for making such interesting videos and the high quality subtitles. I’m almost completely deaf and don’t have hearing aids, and RUclips’s auto generated subtitles are hot garbage.
I love your channel, even though I'm kinda slow with mechanical engineering concepts, I learn so many things from your videos
Great video and thanks for reminding me of those days.
In the 80’s I was a big Yamaha fan and loved my 2-stroke RZ 350 and 500 bikes but was amazed at the tenacity (I probably called it something else back then) of Honda to push 4-stroke engineering in the NR.
Honda applied different ideas when developing the NS, the production NS400R Grand Prix replica was very different from its competitors (RZ500 and RG500). When the production NR finally came out it looked like a possible sport bike future that of course never came to be.
Thank you for this - it is the best, most comprehensive description I have seen of Honda's oval piston adventure. Excellent!
Top tier documentation from you again. Thumbs up!!
When I was in grad school I read the sae technical paper honda published on the nr development. The oval piston shape derived from practical limits on bore to stroke ratio & max piston speed which indicated they needed a v8 to make the horsepower. Since rules said max of 4 cylinders they "siamesed" pairs of cylinders. The 8 valves were a fortuitous side effect.
Fantastic, that old Honda sounded great
Very well told story!
Nice video, it’s refreshing to see someone cover the NR story from a different perspective. As someone who studied in substantial detail the overall story, achievements and failures, I can say that there are way more anecdotes and milestones that are worth sharing. Perhaps at some point I will make a video on this topic too 🙂
Thank you for this!!!
In 1981 I was working with a group at Sears Point Raceway where we were trying to clad the cylinder wall of the oval pistons with a ceramic material. The idea was to increase the combustion temps for more power while providing better wear characteristics with synthetic oils.
Machining was just to difficult at that time, mostly due to the material need to be ground versus other methods because it was so hard.
That NR750 it's the stuff sport motorcycle's dream of becoming one day when they grow up. 👌😍👍
Thanks once again for such an interesting insight to engine design, and clear concise presentation.
once again you have made an impressive and informative video - love it! thanks for your good work! 🤘
Thanks for another great video with a fantastic conclusion!!! 😃
I am so impressed with your presentation that I subscribed half of the way through this video. The first of yours that I have seen. Keep up the good work, KID!
I'm not sure which impresses me more, Honda's vision and persistence or the research you did in order to present this video - in any case thank you very much and I have to say your style is excellent and you speak very clearly, looking forward to watching more of your videos and of course I just subscribed.
Totally agree! Honda is a legendary company, and trying new things is a macho move! Imagine how boring the world would be without fresh ideas!