Shop talk on piston ring end gaps. Do you file them or not? And or why not? Donate Race Fuel link... www.paypal.com... Thanks for watching! upallnight91@hotmail.com
I stumble on your channel couple weeks ago and I can’t stop watching. You’re a great teacher and mechanic. After 50 plus years of riding dirt bikes and doing my own mechanic work I have gained a ton of knowledge from you. Thanks for sharing and taking the time to make videos for us not so good mechanics
Brilliant video! I have filed down wiseco piston rings because of the discrepancy between the manual and the wiseco instructions. Also I noticed that they changed the verbiage in the manual for the yz250 and it only gives the limit measurement and doesn’t give standard range measurements. Anyways thanks to you I don’t bother with it anymore and have had 0 problems. Thanks!
I LOVE Speed Bleeders for brakes and clutches. You can cross reference your thread pitch and size on Russels chart and buy the right bleeders. I can do my bike or truck in a couple minutes by myself.
In the Wiseco instructions they mention that engine work MAY require you to adjust the end gap & they give you some filing instructions also. Makes sense since engine mods may change operating temperatures & piston/ring expansion, right? I'm just doing my homework for an inline 4 bike engine rebuild. Great vid!
Hello. From my understanding the reason you may need to run a wider gap would be for some type of forced induction like a turbo or blower or nitrous. But for a naturally aspired motor its safe to follow the standard ring gap recommendations no matter how modded it is as long as its still N/A.
@@UpAllNight91Alright. Another question/comment though: I read an article that said the ring gap varies slightly as the piston moves up and down the bore of the cylinder; this is due to cylinder taper from wear. If you're just changing the piston(s) and/or rings on a used cylinder, would you worry about the ring gap at the bottom of the stroke? Most measurements for ring gap are done near the top of the stroke, but my manual says to measure ring gap at the bottom of the cylinder.
@@AyPapi69 I would measure the ring gap where the least amount of cylinder wear is just to be safe if its a 4 stroke cylinder. On a 2 stroke cylinder its better to measure more up top because down towards the bottom you have the ports and stuff so its best to measure up top some.
Hello. The Honda manual does not mention the min or max piston ring clearance, they only suggest how many hours to run it before replacing in race conditions. Just like mentioned in the video. If its a OEM piston going into a stock nickel plated bore then no need to worry, just put the ring and piston in. If its a aftermarket piston like wiseco then follow wisecos guidelines for ring end gap.
@@UpAllNight91I was gonna ask for the same video idea, I personally run cast vertex pistons in my 2 strokes, since they have tighter tolerances over forged, and since the piston is lighter than forged it’s easier on the crank bearings. Also the cast is softer so possibly less wear to the cylinder, that’s just what I’ve come by over my research, but I’m curious to hear your opinion on cast vs forged for 2 strokes
@@awesomeproducts1582 Right on. I will try to put a video together on it in a week or two. Going on a little dirt bike camping vacation later this week. Camping out at croom. When you compared the piston weights did you also include the wrist pin that comes with the piston?
@@UpAllNight91 so I didn’t compare weights, I saw this video on UA-cam and this guy went pretty into depth on them…. I forget his name, I’ll find it. Also I heard that forged has a bigger tolerance of piston to cylinder when cold so you get a little piston slap until the bike is warmed up, which overtime causes cylinder wear. Not sure if that’s true but something to consider
@@awesomeproducts1582 Right on. When I weigh a stock YZ250 piston with the rings and wrist pin in the piston it comes out a hair heavier than the wiseco's YZ250 pro light piston with the rings and wrist pin. However if I don't include the wrist pins then the YZ250 stock piston comes out a hair lighter. So overall the wiseco is lighter when assembled on the bike. The issue I see with cast pistons is they break when used by faster riders. When they break they can damage stuff like the cylinder, cases, and crank. Not to mention its dangerous for the rider because it usually locks up the rear wheel. This doesnt seem to be a issue with slower riders or if the bike is used for trail riding or play riding. But it surely becomes a issue with a rider that is getting over all the jumps on the track. I have seen so many broken cast pistons from faster track riders that I cant suggest them at all for a track rider. For what its worth if you pay pro circuit to put together a built race motor for you it will surely come with a forged piston, usually a wiseco brand. I will cover all this in better detail in the video when I get time to put it together but nothing wrong with the cast pistons, as long as they are not pushed too hard by a faster rider they work well.
Hello. If its a nickel plated cylinder its not suggested. The honing on a nickel plated cylinder is only done on a fresh plating, after that you do not want to hone anymore. There is a video that explains this well, here is a link ua-cam.com/video/vaFp8aYkHNA/v-deo.html
My brother and I have noticed a performance gain. Its small but its there. The piston is lighter and changes the balance factor of the crank for more crank inertia. The rings seal a little better and the piston crown is a hair higher which boost compression a tad amount as well as tightens the squish a hair too.
@@UpAllNight91 Yeah the stock YZ250 piston is just a little bit lazier in the mid to upper power curve compaired to a Wiseco Pro Lite.. Plus the rings are not as durable on the OEM units.
Up all night is right I replace my piston 2 weeks ago with wiseco piston I didn't measure the end gap I threw it n my mechanic was not happy about it but bike good it has more power now but next time he will check ring gap
Im currently doing a top end on a husky 125 , wiesco the gap is 0.28 mm , it seemed tight to me , called wiesco they said it seem tight also n said to go with service manuel wich is 0.40 mm with no minimum or max range not sure wich way to go here any help would be apriciated here , thankyou
Hello. If we follow the math on the instructions that wiseco provides with the piston (0.004" gap per inch of bore) the bore for the tc125 is 2.126". That calls for a gap of 0.008504". Convert 0.008504 into metric and that's 0.2160016mm (0.22mm rounded up). So as long as the gap is bigger than 0.22mm its good. If your at 0.28mm you are good to go. Drop her in and run her! She's right on!
I stumble on your channel couple weeks ago and I can’t stop watching. You’re a great teacher and mechanic. After 50 plus years of riding dirt bikes and doing my own mechanic work I have gained a ton of knowledge from you. Thanks for sharing and taking the time to make videos for us not so good mechanics
Ahh man thats awesome to hear! Glad to hear its been of help. Thanks for watching and also thanks for reaching out!
Brilliant video! I have filed down wiseco piston rings because of the discrepancy between the manual and the wiseco instructions. Also I noticed that they changed the verbiage in the manual for the yz250 and it only gives the limit measurement and doesn’t give standard range measurements. Anyways thanks to you I don’t bother with it anymore and have had 0 problems. Thanks!
Right on! See ya tomorrow at 74!
I LOVE Speed Bleeders for brakes and clutches. You can cross reference your thread pitch and size on Russels chart and buy the right bleeders. I can do my bike or truck in a couple minutes by myself.
Right on! I have also had luck with vacume bleeders as well.
I bought a wiseco piston for my yz250 and yes it was tight and not in spec with manual, so I never used it, I still have it on the shelf 😂
Ahh! So you have a good piston on the shelf ready for your next top end!
Another great video!!!
Thanks Brother!
In the Wiseco instructions they mention that engine work MAY require you to adjust the end gap & they give you some filing instructions also. Makes sense since engine mods may change operating temperatures & piston/ring expansion, right?
I'm just doing my homework for an inline 4 bike engine rebuild. Great vid!
Hello. From my understanding the reason you may need to run a wider gap would be for some type of forced induction like a turbo or blower or nitrous. But for a naturally aspired motor its safe to follow the standard ring gap recommendations no matter how modded it is as long as its still N/A.
@@UpAllNight91Alright. Another question/comment though: I read an article that said the ring gap varies slightly as the piston moves up and down the bore of the cylinder; this is due to cylinder taper from wear. If you're just changing the piston(s) and/or rings on a used cylinder, would you worry about the ring gap at the bottom of the stroke?
Most measurements for ring gap are done near the top of the stroke, but my manual says to measure ring gap at the bottom of the cylinder.
@@AyPapi69 I would measure the ring gap where the least amount of cylinder wear is just to be safe if its a 4 stroke cylinder. On a 2 stroke cylinder its better to measure more up top because down towards the bottom you have the ports and stuff so its best to measure up top some.
@@UpAllNight91 Thank you for your reply. I appreciate it. The engine I'm working on is an inline-4 motorcycle engine.
@@AyPapi69 Your welcome. I have done a few of them before. Surely interesting doing 4 in a row.
Hey brother. I love your work
Thanks Brother!
Just bought a new piston for my cr80r stock bore what would be the right ring gap thanks much appreciated 👍
Hello. The Honda manual does not mention the min or max piston ring clearance, they only suggest how many hours to run it before replacing in race conditions. Just like mentioned in the video. If its a OEM piston going into a stock nickel plated bore then no need to worry, just put the ring and piston in. If its a aftermarket piston like wiseco then follow wisecos guidelines for ring end gap.
Can you make a cast vrs forged pistons vid?
Yes I will put together a video on pistons here in the next coming weeks.
@@UpAllNight91I was gonna ask for the same video idea, I personally run cast vertex pistons in my 2 strokes, since they have tighter tolerances over forged, and since the piston is lighter than forged it’s easier on the crank bearings. Also the cast is softer so possibly less wear to the cylinder, that’s just what I’ve come by over my research, but I’m curious to hear your opinion on cast vs forged for 2 strokes
@@awesomeproducts1582 Right on. I will try to put a video together on it in a week or two. Going on a little dirt bike camping vacation later this week. Camping out at croom. When you compared the piston weights did you also include the wrist pin that comes with the piston?
@@UpAllNight91 so I didn’t compare weights, I saw this video on UA-cam and this guy went pretty into depth on them…. I forget his name, I’ll find it. Also I heard that forged has a bigger tolerance of piston to cylinder when cold so you get a little piston slap until the bike is warmed up, which overtime causes cylinder wear. Not sure if that’s true but something to consider
@@awesomeproducts1582 Right on. When I weigh a stock YZ250 piston with the rings and wrist pin in the piston it comes out a hair heavier than the wiseco's YZ250 pro light piston with the rings and wrist pin. However if I don't include the wrist pins then the YZ250 stock piston comes out a hair lighter. So overall the wiseco is lighter when assembled on the bike. The issue I see with cast pistons is they break when used by faster riders. When they break they can damage stuff like the cylinder, cases, and crank. Not to mention its dangerous for the rider because it usually locks up the rear wheel. This doesnt seem to be a issue with slower riders or if the bike is used for trail riding or play riding. But it surely becomes a issue with a rider that is getting over all the jumps on the track. I have seen so many broken cast pistons from faster track riders that I cant suggest them at all for a track rider. For what its worth if you pay pro circuit to put together a built race motor for you it will surely come with a forged piston, usually a wiseco brand. I will cover all this in better detail in the video when I get time to put it together but nothing wrong with the cast pistons, as long as they are not pushed too hard by a faster rider they work well.
Hi, I have a 2002 yz125. Do I have to hone the cylinder before installing new piston and rings? Thanks
Hello. If its a nickel plated cylinder its not suggested. The honing on a nickel plated cylinder is only done on a fresh plating, after that you do not want to hone anymore. There is a video that explains this well, here is a link ua-cam.com/video/vaFp8aYkHNA/v-deo.html
A medição do gap e muito importante e uma forma de saber se a retifica foi bem feita, voce esta errado !!!
I dont think I am and I think I explained it pretty well in the video. Thank you.
By switching to a Weisco piston is there any performance gain or just dependability? Thanks for the videos
My brother and I have noticed a performance gain. Its small but its there. The piston is lighter and changes the balance factor of the crank for more crank inertia. The rings seal a little better and the piston crown is a hair higher which boost compression a tad amount as well as tightens the squish a hair too.
@@UpAllNight91 Yeah the stock YZ250 piston is just a little bit lazier in the mid to upper power curve compaired to a Wiseco Pro Lite.. Plus the rings are not as durable on the OEM units.
Up all night is right I replace my piston 2 weeks ago with wiseco piston I didn't measure the end gap I threw it n my mechanic was not happy about it but bike good it has more power now but next time he will check ring gap
@@michaelgarland579 Right on! They are plug and play
Im currently doing a top end on a husky 125 , wiesco the gap is 0.28 mm , it seemed tight to me , called wiesco they said it seem tight also n said to go with service manuel wich is 0.40 mm with no minimum or max range not sure wich way to go here any help would be apriciated here , thankyou
Hello. If we follow the math on the instructions that wiseco provides with the piston (0.004" gap per inch of bore) the bore for the tc125 is 2.126". That calls for a gap of 0.008504". Convert 0.008504 into metric and that's 0.2160016mm (0.22mm rounded up). So as long as the gap is bigger than 0.22mm its good. If your at 0.28mm you are good to go. Drop her in and run her! She's right on!
OH, thank you for the break down , I learned somthing here , good riding
@@jeffwendorf170 Yes sir! You too!
Where can I download the manual for free?
You can get the yamaha manuals for free right from yamaha, here is a link library.ymcapps.net/library/om/app/index.html?baseCode=6150&langId=02