45 years ago I put new rings in my 500cc single cylinder AJS. That night I went for a ride along Gilchrist Ave Herston (way before the Inner City Bypass was constructed). It was a cool night and I gave it a bit of throttle and within 15 seconds the motor started going slower and slower. I declutched and the motor immediately stopped. The motor was seized. Could not turn it over. After about 5 minutes it unseized and I could turn it over but it was still 'firm' in the turning. I waited until it spun freely and gently rode it home. The next day I took the head and cylinder off and filed the rings down (I don't remember how much). I reassembled the motor and did not have a problem after that. Yes, ring gap is important.
Spot-on Matt. The importance of having the correct ring gap is indeed critical for smooth running pistons along with having rings gaps opposed 180 degrees.
My two stroke has pins that register in the ring gap to keep the rings in a specific orientation, and they are less than 90 degrees apart, but I’m pretty sure that this is because of the porting. Wouldn’t want the gap to be hitting port edges
@@1495978707that’s why exactly! it’s the port’s! On a 4 stroke though it’s not nearly as important,a lot of engines they actually rotate! But typically face the gap’s away off the load side and away from the exhaust valve as that being a hotter area is usually the start point of pre ignition in most engines!
sorry to be so offtopic but does anybody know a trick to get back into an instagram account? I stupidly lost the password. I would love any tricks you can give me
@Jagger Tadeo thanks for your reply. I got to the site through google and Im waiting for the hacking stuff now. Looks like it's gonna take quite some time so I will get back to you later with my results.
Funny how you linked Eric the Car Guy. He's great info for cars and you're the best motorcycle "scientist" out there. Addicted to your videos. Been trying to get through all of them past couple of days...not working, too many. I'll keep trying though!
AvE sent me too. I see why now. Good stuff to know when working with piston and rings. Ya always "mind your gaps", the old timers would say. You just expertly explained why.
Nice explanation Matt, it reminded me of chatting to Steve Patrickson in the paddock at Donington after his bike seized in practice on the run down to Redgate, must be over 25 years ago. The weather was a little hotter than predicted and the rings grabbed. In his situation that last ounce of power on a 125 was of paramount importance but of course the gap wasn't too far out to cause any lasting damage. That was the first time I'd heard of ring grab and it explained what had happened to me a couple of times in hot weather a few years before.
Thank you for the help , I just got new pistons and rings took my pistons and jugs to be bore 10th over size the Bore is 3 inch and 510th the ring gap was 22th but by the math the ring gap should be 16th or 17th but S&S pree set the gap for the chrome moly at 22th spec sheet has 18th to 22th , the piston to bore is 2.5th clearance , Ring 2 is cast iron has a gap of 28th and that has me worried S&S has the gap between 18 and 24 thousands , the oiler ring gap is at 35th but can go to 40th , I was thinking to big of a gap and you get blow by , But test have been done and even a ring gap of 1/4 inch did not change engine performance or burn oil . The test was done by Chevy on the V6 and V8 , not a Harley Davidson .
@@jediknight1294 Yes I went with the S&S rings that been pree set and 2000 miles I was getting blow by ordered a new set 20 over did a quick hone on the jugs , cut the gap 18 top ring 18 second ring the oil ring was 26th so left it be. been good 5000 miles no blow by or leak down
Need some advice. I have a single cylinder thumper motor in my bike. It had a transmission issue. I removed the engine from the frame repaired the tranny issue and then put the motor back together. No compression. Don’t understand why, never messed with the piston. Replaced all gaskets. Torqued to specs. Still no compression. Got new gaskets again, did an inspection on the head and valves. Finally did a lap job on valves. Checked the valve guides, seats, seals and valves. All are on. Bike only has 3000 miles on it. But it ran perfectly aside of he tranny issue. So, back in the motor with brand new piston rings. Still no compression. Double checked the clocking and directions of the gaps. Checked ring gaps and thickness. These are NOS parts by the way. New Or Stock parts. I need @140psi and I’m only getting @45psi. I also did leak down test and I can hear air hissing in the crank case, evidently getting past the piston rings. The valves are sealed tight. Again, the rings are brand new from the manufacturer, clocked correct, directional, gaps are good, applied assembly oil, followed the specs. Still getting blow by. Anyone got any advice.?
The Workshop This is on a 2003 Buell blast. 500cc. 4stroke Most people would say, just toss this crap bike, but I actually like these bikes and have five of them, well, two now. I sold one, kept two and gave two away to my step sons. Also with 4 other Buells. XB9R, xb12r, M2 cyclone and 1125r. Anyhow, yes, this is with the valves closed. I put the rocker box back on and was struggling on keeping the valves closed while locating TDC, and then compressing the cylinder with compressed air. I had it in 3rd gear to help prevent the rotation of the engine, but still there’s engine movement. So, instead of installing the rocker box, I just left it off. Valves are now 100% sealed off. Did a compression check again, 45psi. Added compressed air and heard no air from the intake or exhaust. But instead, I hear air hissing from the primary when I removed the timing window screw. Again, new rings, gapped within specs. Between .007-.020. Actual is .014. Max before OS is .035. I’m still getting blow by and when starting with compression Check gauge, it’s showing 45psi. I even double checked the compression gauge tool by testing it on the M2 cyclone, which gave a reading of 140psi.
I had a Honda SL 70 as a kid the trans had a drive chain to the cam if the dot on the timing was not set right the cam opened the valves timing was way off . Handa had trans fail on the 1970 SL 70 they would give you a trans kit all gears seals free , if they did the work it was 45 a hour , I had a paper rout lucky to make 30 bucks a week , so I got my dad to help me rebuild it took 4 tries to get the cam right .
Is minimum gap too risky due to heating? Should max gap be used? Re-ringing an old Chevy 235-6 low HP engine by modern standards. Well presented topic! 👍
cross hatch will make the rings rotate,(not Much but they do move around) unless they are pinned, ring gaps are very important, the second ring on a four stroke, can be a gapless design.
I've one question temp is required for expansion of piston ring but at starting of engine temp is very low so rings will not expand and joinds are not attached one end to other end so small gap will be present at initial so the mixture will not compressed properly right? Plzz reply
Thank you good sir! :) Great descriptions and everything. I remember gapping my rings the one time i've done it. Didn't understand why but did it anyway and then clocked them, you explained it perfectly!
Here's a thing that i didn't (and still don't) understand: If you run a 2stroke there is a fresh mixture above and underneath the piston and little (piston ring) gap especially when cold. What preventing the "flame" from traveling through?
Nothing, but its a choke point. This is why you have a large cone around you're spark plug. Flame fronts combust and release heat, this in turn heats the fuel/air ahead of it. The tiny ring gap and the rings themselves absorb this heat and the flame front is killed off. Great question. Video coming soon.
THX for the (quick) reply, so it's that simple ?! I knew there had to be something otherwise every 2stroke ever build would have exploded at first start ;) Didn't expect this answer, always thought that an ignited fuel-air mixture was unstoppable (behaving gunpowder like) BTW it's an very old question that I had examining the piston of my first moped, witch was black underneath the top ring (yes it had 2) about 30 years ago!
AvE suggested I come over and check you out. Who are you talking too? It was a very good and thorough explanation. I subscribed and looking for more good, solid content like this. Thanks, Joe
"Who are you talking too?" - LOL I'm not very good at this presenting thing - well at least not at a camera - but I'm getting better - this is at least 6 months old. But anyroad - welcome to the channel dude
Actually I've never really bothered to measure it on my bikes. I should but I've not actually replaced any rings yet. Also I'd think most heat from the piston is removed by the incoming air/gas mixture. Thanks for this and your other videos :)
It surprises me that these oil rings and the holes under them that return the oil back inside the piston don't clog. Wouldn't they block once the oil gets old and oil changes aren't done regularly.
hi i have this issue of starting my car it hard for it to move until 5 mins of run and hot in engine before gaining pressure to move can any one advice on what to do ,it a honda accord engine 1999 model
Also I filed my ring on just one side. Just needed a little bit for spec but now it’s good. I think it’s a little angled just a touch. Any how what if the rings where angled a bit off on both sides but still in spec? The piston manufacture wants the rings flat and even shows a pic saying to be sure the rings are filled flat. Is this little bit able to make a difference?
That's why I said still in spec. meaning the gap is in tolerance with a feeler gauge but the corners are a little bit wider but still barely in spec on the corners. It is angled ends instead of flat. Will that make a difference while running?
Had to take an inch off of the top oil ring so it would fit into the already honed cylinder. Piston was out of spec and oil groove wasn't deep enough. After buying pistons and rings twice, can't afford this anymore. Tried to make lemonade from a lemon. Best I could do given the situation. What might I expect with one of the four rings having that much of an end gap. Just a shade tree mechanic I am. And poor as hell to boot.
Yes, it does, like a hypereutectic piston its reflecting heat, that means a little more heat put on that ring. I would recommend a couple more thou in gap
i'm going to link a video here of what happens is you don't gap the rings larger on a nitrous boosted engine, it should be pretty easy for people to make the conclusion that having to gap bigger because of more heat is the same as not gaping enough for normal heat
My 250 Suzuki atv rings wore out, the top ring is a barrel faced ring and the second one is a tapered, I broke the new second ring during installation, and put the old one back , upside down (heck if I know) with new oil control rings and it runs just fine the old top ring was 0035 and the new one measured out at 0015, the used second ring was around 0023, I run a soft hone on the sleeve and hand polished it with 600 wet dry paper, guess what no more smoke, besides the top ring is the one that holds compression, and the second is just a scraper, and I figure if it lubes more oil the better off the cooling. we will see what happens after 500 miles.
Got a question for you, I built an engine (4cyl iron block 89.00mm bore), I bought a set of piston rings for the stock bore size from some company. DNJ Piston rings I believe, I tried calling them or their manufacturer and I didn't get any information. I forgot to check my piston ring gap, this is an NA engine by the way. I was told by many that the ring gap is usually already there for stock applications, and that you will usually get an oversized ring instead of an undersized one sometimes. Should I be worried or no? I still haven't started the engine yet. Was also told that machine tolerances are pretty high as well. Thank you.
@@dirtygarageguy Didn’t measure, what are the chances of something bad happening? Rings were ordered for stock bore size, unknown mileage on engine (KA24DE from the 90s), honed the cylinders down. I was under the assumption that the rings ordered for the stock bore size were pre-gapped. I’ve yet to start the engine.
Always went by an ancient prophecy by a long passed ancient assembler. .004 per inch of cylinder diameter unless otherwise stated or forced induction in which case multiply .004 by the number of sockets in an Aldi toolkit 🤪. Ps. First bit is correct and never failed me.
i have a sr20ve engine an only when i rev the engine pass 6000rpm it pump's white oil smelling smoke from the exhust...could dis be faulty rings or gap //the gap it 0.022....is dat good for the sr20ve.???
My advice as an amateur 2 stroke mechanic...always use original items..if you go aftermarket just choose expensive brandts and good quality products..NEVER use cheap aftermarket products...the little amount of money you will save in that case you ll need it (and much more)to repair the damage that will be done...i never had problems with original parts and i never measure gaps ...trust me
is there any truth to the theory that if your engine is a bit tired and using more oil than usual between services you should up the weight say from 5w30 to 5w40 providing both have the same spec i know its now weight but hopefully you get what i mean
No. Weight is an Americanism that should be banned lol as engines wear the clearance increase. This means a steady drop over time in oil pressure. Using thicker oil doesn't help this in any way.
Hi matt been watching your videos for a while Now, keep it it buddy Maybe a video idea Is supermarket fuel inferior to other major brands And. What are. Your thoughts on ktms 3 stroke, They are developing.
Why is ring gap orientation important? I’m building a 2009 KX250F big bore kit from Cylinder works. But they are admit the gaps on the 4 rings point in specific orientations.
Joking aside....i havent joked on this video yet tho.... Anyway im more a cut it hit it grind it weld it bloke being a commercial vehicle bodybuilder by trade so i didnt know about this so ive learned summat 🖒🖒
me, I change the rings of pistons diesel engine 2.0 l ... but now I notice the smoke that comes out of the oil cap with the motor rhythm, after asking the mechanic he confirm me that it will leave with the time, is it normal? ... I drove 250 km with the car, of course having to let it run 8 days in idle for reasons of 8 hours per day, now the draw of the car is a lot better but the story of the smoke, r disturbs me
Heya man, diesels do normally have a fair bit of blow by and crankcase pressure naturally but without seeing it I'm only guessing how bad it is. A compression test can give a good idea of what's going on in the cylinders and is fairly easy to do yourself or cheap to have done. If she's hard to start or low on power, oils all watered down or blowing excessive smoke then there may be an issue. If she starts nice and shows decent compression across the cylinders ya probably ok.
@@brotangyoust9252 thanks for the answer, The start is nice , as the power it's better then before changing the gaps of pistons, but I don't know if it's on the top or not because it's yet in break-in period and I think it's not advisable to force the engine, but overall the power is good , As compression test I have not the measuring device, may be I will do it in the future, as the quantity of smok it's not lot, it's just when the engine is hot, and I will make video of the engine working, thank you
ring= steel piston=aluminium expansion of aluminium is way bigger than steel so piston grows more than ring groove in piston gets bigger along with piston how can gap get smaller?
The rings are retained by the cylinder, as the rings heat up due to heat transfer from the piston and friction with the cylinder wall the ring expands in the only way it can.
![Megan Thee Stallion - Roc Steady (feat. Flo Milli) [Official Video]](http://i.ytimg.com/vi/HozPPyqW0dY/mqdefault.jpg)
45 years ago I put new rings in my 500cc single cylinder AJS.
That night I went for a ride along Gilchrist Ave Herston (way before the Inner City Bypass was constructed).
It was a cool night and I gave it a bit of throttle and within 15 seconds the motor started going slower and slower. I declutched and the motor immediately stopped. The motor was seized. Could not turn it over. After about 5 minutes it unseized and I could turn it over but it was still 'firm' in the turning. I waited until it spun freely and gently rode it home.
The next day I took the head and cylinder off and filed the rings down (I don't remember how much).
I reassembled the motor and did not have a problem after that.
Yes, ring gap is important.
Cool story 👍
Spot-on Matt. The importance of having the correct ring gap is indeed critical for smooth running pistons along with having rings gaps opposed 180 degrees.
My two stroke has pins that register in the ring gap to keep the rings in a specific orientation, and they are less than 90 degrees apart, but I’m pretty sure that this is because of the porting. Wouldn’t want the gap to be hitting port edges
@@1495978707that’s why exactly! it’s the port’s! On a 4 stroke though it’s not nearly as important,a lot of engines they actually rotate! But typically face the gap’s away off the load side and away from the exhaust valve as that being a hotter area is usually the start point of pre ignition in most engines!
Excellent video! I've seen rings pop the tops of pistons off, from having the gaps close up. This is important stuff.
sorry to be so offtopic but does anybody know a trick to get back into an instagram account?
I stupidly lost the password. I would love any tricks you can give me
@Elian Camilo Instablaster ;)
@Jagger Tadeo thanks for your reply. I got to the site through google and Im waiting for the hacking stuff now.
Looks like it's gonna take quite some time so I will get back to you later with my results.
@Jagger Tadeo it did the trick and I now got access to my account again. Im so happy!
Thanks so much you saved my account :D
@Elian Camilo glad I could help xD
I enjoy how simple yet in-depth you go into the topic.
I didn't understand why ring gaps were so important when it comes to engines, now it's all too clear. Thank you my friend.
I dont know whether you are an engineer or not but i love how you explain this topic
Funny how you linked Eric the Car Guy. He's great info for cars and you're the best motorcycle "scientist" out there. Addicted to your videos. Been trying to get through all of them past couple of days...not working, too many. I'll keep trying though!
Thank you for this great video. Your info is consistent with what I’ve read. New pistons, rings and HD wrist pins for my 98 Cobra will be here today!
In depth and easy to understand. Bravo sir!
Mind the gap!
I just replace them with rubber O-rings! Makes a nice suctiony “pop” when they’re removed!
Glad I found this channel.
Excellent mate 👍
Yet another great video that answered a question I didnt even think of asking.
Same, and I’m fitting rings to some slugs tomorrow, I honestly never thought about it, I’m embarrassed
AvE sent me too. I see why now. Good stuff to know when working with piston and rings. Ya always "mind your gaps", the old timers would say. You just expertly explained why.
Welcome to the channel dude
Another sub by power of the AvE wave. Congrats on the shout out, it'll be huge.
Cheers dude and welcome to the channel
New here. Really enjoyed that simply, clear explanation.
It seems so obvious once you know!
Welcome to the channel dude
You have clear conceptual knowledge
Short and VERY useful. Thanks mate!
this made an insane amount of sense, thank you
Nice explanation Matt, it reminded me of chatting to Steve Patrickson in the paddock at Donington after his bike seized in practice on the run down to Redgate, must be over 25 years ago. The weather was a little hotter than predicted and the rings grabbed. In his situation that last ounce of power on a 125 was of paramount importance but of course the gap wasn't too far out to cause any lasting damage. That was the first time I'd heard of ring grab and it explained what had happened to me a couple of times in hot weather a few years before.
Very true and great comment, video added to the list - 'ring grab, when a woman keeps your wallet for life' lol
@@dirtygarageguy Still waiting on this video! lol
Keep waiting, this isn't a service.
@@dirtygarageguy Never thought it was! Good video by the way. made me recheck my ring gap on the motor I'm about to put the the cylinders on.
@@dirtygarageguy Really? I thought the service came as part of the ring grab.
New subscriber, great channel, loads of great content, keep up the great work Matt 👍
welcome to the channel dude
Excellent explanation ! well done
Thank you for the help , I just got new pistons and rings took my pistons and jugs to be bore 10th over size the Bore is 3 inch and 510th the ring gap was 22th but by the math the ring gap should be 16th or 17th but S&S pree set the gap for the chrome moly at 22th spec sheet has 18th to 22th , the piston to bore is 2.5th clearance , Ring 2 is cast iron has a gap of 28th and that has me worried S&S has the gap between 18 and 24 thousands , the oiler ring gap is at 35th but can go to 40th , I was thinking to big of a gap and you get blow by , But test have been done and even a ring gap of 1/4 inch did not change engine performance or burn oil . The test was done by Chevy on the V6 and V8 , not a Harley Davidson .
Did you change the gap or go with S&S spec and if you altered the gap did you see any issues compared to standard spec?
@@jediknight1294 Yes I went with the S&S rings that been pree set and 2000 miles I was getting blow by ordered a new set 20 over did a quick hone on the jugs , cut the gap 18 top ring 18 second ring the oil ring was 26th so left it be. been good 5000 miles no blow by or leak down
Fantastic , very clear, new follower.
Need some advice. I have a single cylinder thumper motor in my bike. It had a transmission issue. I removed the engine from the frame repaired the tranny issue and then put the motor back together. No compression. Don’t understand why, never messed with the piston. Replaced all gaskets. Torqued to specs. Still no compression. Got new gaskets again, did an inspection on the head and valves. Finally did a lap job on valves. Checked the valve guides, seats, seals and valves. All are on. Bike only has 3000 miles on it. But it ran perfectly aside of he tranny issue. So, back in the motor with brand new piston rings. Still no compression. Double checked the clocking and directions of the gaps. Checked ring gaps and thickness. These are NOS parts by the way. New Or Stock parts. I need @140psi and I’m only getting @45psi. I also did leak down test and I can hear air hissing in the crank case, evidently getting past the piston rings. The valves are sealed tight. Again, the rings are brand new from the manufacturer, clocked correct, directional, gaps are good, applied assembly oil, followed the specs. Still getting blow by. Anyone got any advice.?
1) - what engine is this from?
2) - this is with the valves closed? - I know this sounds stupid but I need to ask
3) 2 troke or 4 stroke?
The Workshop
This is on a 2003 Buell blast. 500cc. 4stroke
Most people would say, just toss this crap bike, but I actually like these bikes and have five of them, well, two now. I sold one, kept two and gave two away to my step sons. Also with 4 other Buells. XB9R, xb12r, M2 cyclone and 1125r.
Anyhow, yes, this is with the valves closed. I put the rocker box back on and was struggling on keeping the valves closed while locating TDC, and then compressing the cylinder with compressed air. I had it in 3rd gear to help prevent the rotation of the engine, but still there’s engine movement. So, instead of installing the rocker box, I just left it off. Valves are now 100% sealed off. Did a compression check again, 45psi. Added compressed air and heard no air from the intake or exhaust. But instead, I hear air hissing from the primary when I removed the timing window screw. Again, new rings, gapped within specs. Between .007-.020. Actual is .014. Max before OS is .035. I’m still getting blow by and when starting with compression Check gauge, it’s showing 45psi. I even double checked the compression gauge tool by testing it on the M2 cyclone, which gave a reading of 140psi.
Tommy Escobia. Is the intake to the head fully open and the throttle open. Insufficient air in could keep you from reaching full compression.
I had a Honda SL 70 as a kid the trans had a drive chain to the cam if the dot on the timing was not set right the cam opened the valves timing was way off . Handa had trans fail on the 1970 SL 70 they would give you a trans kit all gears seals free , if they did the work it was 45 a hour , I had a paper rout lucky to make 30 bucks a week , so I got my dad to help me rebuild it took 4 tries to get the cam right .
Avoid the headache, use Totalseal rings.
4th battalion of the AvE Army reporting for duty!
Sir" super explanation... thanks
Excellent video, thank you
After reading the comments, and seeing this vid, you've gained another sub. ( AvE didnt send me, you showed in my recommended) good day!
Welcome to the channel dude
Thank God and you for your video.
A proper informative video, thank you. And not one mention of Delboy.
AvE sent me 10 seconds ago
Well I just learned why my originality non turboed engine is now in the machine shop after I turboed it.
So the second ring doesn't seal much cause its not pushed out much from the combustion pressures?
Thank you very good explanation 😊 thank you
Excellent presentation, thankyou. ✔
Is minimum gap too risky due to heating? Should max gap be used? Re-ringing an old Chevy 235-6 low HP engine by modern standards. Well presented topic! 👍
For reliability in between max and min is a good place to start
Thanks!
Great explanation!!
Came from AvE. Great video! Seems obvious, but someone had to point it out to me! =D
Welcome to the channel dude
cross hatch will make the rings rotate,(not Much but they do move around) unless they are pinned, ring gaps are very important, the second ring on a four stroke, can be a gapless design.
Holy shit I just got schooled on piston rings.
I've one question temp is required for expansion of piston ring but at starting of engine temp is very low so rings will not expand and joinds are not attached one end to other end so small gap will be present at initial so the mixture will not compressed properly right? Plzz reply
Interesting video, another engineering mystery is brought to light and tamed!!
AVE subs inbound... you've got a new sub :) And more incoming I suspect. Great video! :)
Welcome to the channel dude
Thank you good sir! :) Great descriptions and everything. I remember gapping my rings the one time i've done it. Didn't understand why but did it anyway and then clocked them, you explained it perfectly!
Excellent video, yours is the best I have seen on RUclips thanks for the video !!!
cheers dude
We have to related somewhere down the line.
Here's a thing that i didn't (and still don't) understand:
If you run a 2stroke there is a fresh mixture above and underneath the piston and little (piston ring) gap especially when cold.
What preventing the "flame" from traveling through?
Nothing, but its a choke point. This is why you have a large cone around you're spark plug. Flame fronts combust and release heat, this in turn heats the fuel/air ahead of it. The tiny ring gap and the rings themselves absorb this heat and the flame front is killed off.
Great question. Video coming soon.
THX for the (quick) reply, so it's that simple ?!
I knew there had to be something otherwise every 2stroke ever build would have exploded at first start ;)
Didn't expect this answer, always thought that an ignited fuel-air mixture was unstoppable (behaving gunpowder like)
BTW it's an very old question that I had examining the piston of my first moped, witch was black underneath the top ring (yes it had 2) about 30 years ago!
AvE suggested I come over and check you out. Who are you talking too? It was a very good and thorough explanation. I subscribed and looking for more good, solid content like this. Thanks, Joe
"Who are you talking too?" - LOL I'm not very good at this presenting thing - well at least not at a camera - but I'm getting better - this is at least 6 months old. But anyroad - welcome to the channel dude
Actually I've never really bothered to measure it on my bikes. I should but I've not actually replaced any rings yet. Also I'd think most heat from the piston is removed by the incoming air/gas mixture. Thanks for this and your other videos :)
"Also I'd think most heat from the piston is removed by the incoming air/gas mixture."
- And goes where? It doesn't disappear...
It surprises me that these oil rings and the holes under them that return the oil back inside the piston don't clog. Wouldn't they block once the oil gets old and oil changes aren't done regularly.
hi i have this issue of starting my car it hard for it to move until 5 mins of run and hot in engine before gaining pressure to move can any one advice on what to do ,it a honda accord engine 1999 model
Great Video !
Also I filed my ring on just one side. Just needed a little bit for spec but now it’s good. I think it’s a little angled just a touch.
Any how what if the rings where angled a bit off on both sides but still in spec? The piston manufacture wants the rings flat and even shows a pic saying to be sure the rings are filled flat.
Is this little bit able to make a difference?
It depends on how much - if they butt together then all hell breaks loose
That's why I said still in spec. meaning the gap is in tolerance with a feeler gauge but the corners are a little bit wider but still barely in spec on the corners. It is angled ends instead of flat. Will that make a difference while running?
Valuable info!love the accent
Another piston question: As a racing application could the piston become part of the ignition circuit?
AvE said u was skookum. I agree.
Welcome to the channel dude - loads more video to laugh at
Had to take an inch off of the top oil ring so it would fit into the already honed cylinder. Piston was out of spec and oil groove wasn't deep enough. After buying pistons and rings twice, can't afford this anymore. Tried to make lemonade from a lemon. Best I could do given the situation. What might I expect with one of the four rings having that much of an end gap. Just a shade tree mechanic I am. And poor as hell to boot.
Would ceramic coating the pistons affect ring gap?
Yes, it does, like a hypereutectic piston its reflecting heat, that means a little more heat put on that ring. I would recommend a couple more thou in gap
i'm going to link a video here of what happens is you don't gap the rings larger on a nitrous boosted engine, it should be pretty easy for people to make the conclusion that having to gap bigger because of more heat is the same as not gaping enough for normal heat
My 250 Suzuki atv rings wore out, the top ring is a barrel faced ring and the second one is a tapered, I broke the new second ring during installation, and put the old one back , upside down (heck if I know) with new oil control rings and it runs just fine the old top ring was 0035 and the new one measured out at 0015, the used second ring was around 0023, I run a soft hone on the sleeve and hand polished it with 600 wet dry paper, guess what no more smoke, besides the top ring is the one that holds compression, and the second is just a scraper, and I figure if it lubes more oil the better off the cooling. we will see what happens after 500 miles.
thanks, i would have never known this. U just blew my dumb mind. again..........
set the top ring and second ring 180 from each other also
I have done that. The result is lovely. 💚
Thanks for explaining ring gaps what for I go and destroy an engine thinking I got it under control. 😆
AvE sent me!!! and I subbed
Welcome to the channel dude
I have to replace rings on a friend's Toyota. Should I get OEM rings and pistons so I don't need to grind the rings some with aftermarket?
I'd always go OEM
@@dirtygarageguy I'll do that then, thanks!
Thank you!
The AvE army has arrived
drinking game ::: Drink every time he says ring gap ---- i cant keep up lol
Got a question for you,
I built an engine (4cyl iron block 89.00mm bore), I bought a set of piston rings for the stock bore size from some company. DNJ Piston rings I believe, I tried calling them or their manufacturer and I didn't get any information.
I forgot to check my piston ring gap, this is an NA engine by the way. I was told by many that the ring gap is usually already there for stock applications, and that you will usually get an oversized ring instead of an undersized one sometimes. Should I be worried or no? I still haven't started the engine yet. Was also told that machine tolerances are pretty high as well.
Thank you.
Did you measure the gap? If not, do it now
@@dirtygarageguy Didn’t measure, what are the chances of something bad happening? Rings were ordered for stock bore size, unknown mileage on engine (KA24DE from the 90s), honed the cylinders down.
I was under the assumption that the rings ordered for the stock bore size were pre-gapped. I’ve yet to start the engine.
100% if its the wrong gap... if it were me I'd check, dont check at your own risk
I think this may be my problem. My 70cc 2stroke just lost all compression and started making a weird sound
I think the ring failed
Thank you so much
Craig, Blue and Paul sent me.
This would have been nice to see about a week ago
Cody's Lab sent me to AvE (which RUclips apperently buried in my subs for a long time.) and AvE sent me here. I love good channel references.
Welcome to the channel dude
Always went by an ancient prophecy by a long passed ancient assembler. .004 per inch of cylinder diameter unless otherwise stated or forced induction in which case multiply .004 by the number of sockets in an Aldi toolkit 🤪. Ps. First bit is correct and never failed me.
im beginning to wonder if you ever sleep matt.. iv lost count of your uploads in the past 24 hrs :-)
The secret is 100ml petrol mixed with 50ml of methanol, swallow it whole with about 1/2 kilo of cocaine and you never have to sleep again lol
the two to one ratio of "pethanol" i can handle... the half a weight of coke..... not anymore :-D
i have a sr20ve engine an only when i rev the engine pass 6000rpm it pump's white oil smelling smoke from the exhust...could dis be faulty rings or gap //the gap it 0.022....is dat good for the sr20ve.???
White? Coolant leak. Your head gasket might be leaking or cylinder is cracked
@@dirtygarageguy more like oil residue iin the exhaust valve ports only in #4 cylinder.. ..rite now engine is scrap out ...
Hey do some videos about the screaming eagle Harley Davidson Kits please.
My advice as an amateur 2 stroke mechanic...always use original items..if you go aftermarket just choose expensive brandts and good quality products..NEVER use cheap aftermarket products...the little amount of money you will save in that case you ll need it (and much more)to repair the damage that will be done...i never had problems with original parts and i never measure gaps ...trust me
Thanks I needed this
is there any truth to the theory that if your engine is a bit tired and using more oil than usual between services you should up the weight say from 5w30 to 5w40 providing both have the same spec i know its now weight but hopefully you get what i mean
No. Weight is an Americanism that should be banned lol as engines wear the clearance increase. This means a steady drop over time in oil pressure. Using thicker oil doesn't help this in any way.
@@dirtygarageguy so it wouldnt help the oil burning issue then? full rebuild the best way forward price depending?
I love this to no much about this so I can get connected with you guys
so educational
AvE Sent me here. Heloooo!
makes two of us
Hi matt been watching your videos for a while Now, keep it it buddy
Maybe a video idea
Is supermarket fuel inferior to other major brands
And. What are. Your thoughts on ktms 3 stroke, They are developing.
3 stroke?
@@dirtygarageguy yes i said exactly the same when i heard it.
So always gap piston rings even for stock engines?👀
Why is ring gap orientation important? I’m building a 2009 KX250F big bore kit from Cylinder works. But they are admit the gaps on the 4 rings point in specific orientations.
We'll get to this real soon
Ave Sent me, nice information, good to know.
Can I use a 1mm gap like a reference for any small engine like briggs and stuff couse I don't think it matters that much in small ones!
But does it burn oil when the gap is too big
good learning lesson
I have 125 cc yamaha Rx how i keep cool engine faster it has no rediator plz help me give me some tips
Ave sent me !
Welcome dude
Which ave video sent you guys here????
ruclips.net/video/5CQG5nhsynE/видео.html
Joking aside....i havent joked on this video yet tho....
Anyway im more a cut it hit it grind it weld it bloke being a commercial vehicle bodybuilder by trade so i didnt know about this so ive learned summat 🖒🖒
I build bike engines and that's perfectly explained .
me, I change the rings of pistons diesel engine 2.0 l ... but now I notice the smoke that comes out of the oil cap with the motor rhythm, after asking the mechanic he confirm me that it will leave with the time, is it normal? ... I drove 250 km with the car, of course having to let it run 8 days in idle for reasons of 8 hours per day, now the draw of the car is a lot better but the story of the smoke, r disturbs me
Heya man, diesels do normally have a fair bit of blow by and crankcase pressure naturally but without seeing it I'm only guessing how bad it is. A compression test can give a good idea of what's going on in the cylinders and is fairly easy to do yourself or cheap to have done. If she's hard to start or low on power, oils all watered down or blowing excessive smoke then there may be an issue. If she starts nice and shows decent compression across the cylinders ya probably ok.
@@brotangyoust9252 thanks for the answer,
The start is nice , as the power it's better then before changing the gaps of pistons, but I don't know if it's on the top or not because it's yet in break-in period and I think it's not advisable to force the engine, but overall the power is good ,
As compression test I have not the measuring device, may be I will do it in the future, as the quantity of smok it's not lot, it's just when the engine is hot, and I will make video of the engine working, thank you
@@brotangyoust9252 Hi there , you can see this video
ruclips.net/video/RrVfR_HTGJE/видео.html
the power of knowledge
AVE sent me
Welcome dude - but where's the video?
Its out in a week I spend what little student money on his amazing patron page
The Workshop its out now
ring= steel
piston=aluminium
expansion of aluminium is way bigger than steel
so piston grows more than ring
groove in piston gets bigger along with piston
how can gap get smaller?
The rings are retained by the cylinder, as the rings heat up due to heat transfer from the piston and friction with the cylinder wall the ring expands in the only way it can.
that does explain it
but then... doesnt the cylinder wall also expand.
but then it will not get the same higher temperature so will not expand as much
Good to know