My guess is with all the four stroke bikes out there these days, at the track someone just poured straight gas in it not knowing about old school 2 strokes and 2 stroke oil.
My thoughts as well.. straight gas ⛽️ then boom… then the realization, “forgot the oil” so before returning blown up, oil was added as well as the “I don’t know what happened”
I enjoy watching Joe fix these machines, but the one thing about it is that there's no follow-up on what happens to them once they're fixed. It leaves people to assume they're just piling up on Joe's property. I, for one, would be very interested in what happens to them after they're fixed. A breakdown of how much he paid for them plus repair costs and then ultimately the sale of each of them to see if he either made or lost money or if he broke even would be awesome. Does anyone else feel the same way? Thanks! 👍🏻
Less oil = More fuel = Rich / less oil would create a lubrication problem, not a lean condition; I think Joe is right on, was running way too high air to fuel (lean) created a lot of heat and grenaded the piston. My guess is an air leak down stream from the carb.
@@TroyJohansson-l6f Nope, it's lack of oil in the mix. Yea she was running a bit lean(plug) but not enough to cause that damage. It's pure friction damage. AND he said the locked up in mid jump, amateur rider with no throttle control over reved it. typical ricky racer over reving and constant throttle blipping
@@GoofieNewfie69 Your both wrong he checked the fuel it was colored so it had oil. both jets, air screw, and needle were rich especially the needle so an air leak is a bit unlikely the cause.
@@PurpleMonkeyWaffle It had oil, but how much. By looking at a fuel mix tell me how you can tell the difference between 30/1, 40/1, or 50/1. If you had the fuel and oil that was used, mixed them at varying mixtures, you may see the difference. Barring an evaporative or IR test you don't know what was in it when the piston failed. But the key is in the needle bearings. They take a while to wear out like that, not just a minute or so of overheating. We used to race 2 smokers in the 70's and seen many types of failures, The head shows lean and not enough oil. Pistons grenade like that from overreving, too small for the bore and lack of oil. Now on the other hand, there may have been enough oil in the fuel by not mixed to a homogeneous state(most people put the fuel and oil in a tank and shake it for a few seconds. We always put 1/4 fuel in tank, added required oil for the mix, shook for about a minute, the added another 1/4 fuel shook repeated till all fuel was in. The oil will separate if not mixed very well. It will look like a lean burn on piston, and plug, but the bearings tell a different story. Then the over reving, now-a-days you don't see it so much with rev limiters. Watch a good rider jump vs a ricky racer. Ricky racers usually wind em out in a jump can even hear the limiter kick in , but not good or pro riders
@@GoofieNewfie69 I would lean more towards the fuel mixture being the issue. That bike was meant to be revved in the higher RPM's compared to the bikes of the 70's. Your 100% right that there is no way of knowing what the fuel mixture is. These days, alot of the 2-stroke oils being sold (atleast quality oil) is the same color as the fuel so it is very possible this was just some person that had no idea that oil needed to be mixed with the fuel and they just threw straight pump gas in the bike.
Always replace the crank seals especially when the can't be replaced from the outside. It isn't worth the gamble saying "they look good". This is definitely true when the engine has gotten hot enough to destroy the piston and upper rod bearing.
I watch these vids with my jaw dragging along the floor.... As a home wrencher who oh so often reaches the "I'm scared to go any further" point. To watch someone keep going....no matter what, all filmed with the calm logical narration...Superb, compulsive viewing 5⭐ 👏👏👏
Lmao he sells a lot of the bikes on the channel and buys more to further the content. You really think he’s just fixing these and keeping them? 😂 he has a couple of older videos of what he’s actually kept. Mostly rare or vintage stuff
I always change the top-end bearing with a new piston, they're kinda fragile. Wauw that piston grenaded. Sorry for you for having to rebuild, but once again a great video. Big Up!
Thank you thank you, 2vintage! Your channel inspired and motivated me to buy a 1997 Kawasaki KX250 and work on it myself. Getting it running and ripping has been extremely rewarding. You rock!
I’ve been away so catching up on your videos. This really looks like it’s been run without 2 stroke oil. But I think you got lucky with it. That kind of failure generally ends up with cracked cases. Looking forward to the next one on this bike.
I just bought a 1994 yamaha xt350 and the seller said he was rising and it lost compression. He said he installed a new piston and timing chain and still no compression so I got it for $450, got it home and this thing has stripped cam bolts and broke bolts on exhaust. Has 2 bent valves,original piston original timing chain, and bad wrist pin on the rod side. Loving the honesty. ❤
Great watching you strip down the 1996 kX 250, looking forward to watching you rebuild it, wish you lived near me, my 89 cr 125 hasn't been fired up since 93 ( walsall England )
Wonderful isnt it? Kids got some skills, thats for sure. Has helped me a Lo9t already, been watching him since he had like 20k subs. I always learn Something from is videos, worst case its same thing but Drills the problem solving steps in for good and others a Whole new can o worms :) Cheers.
That is not caused by overheating I made my first comment before the cylinder was pulled off and that looks to be like too much clearance banshees are bad for doing that if you have too much clearance they'll break a piston skirt on the intake side so being that the exhaust side isn't all messed up that wasn't caused by overheating It's either detonation cause the piston to break which it can do or there was too much clearance for the piston and it just rattled back and forth till it broke the skirt The reason it'll break on the intake side if it's too much clearance is because that's the on the upstroke for its compression stroke that's the stress side of the piston that's the side of the piston that all the pressure is put on as the rod transitions to going back up there's always a little bit of side load on the skirt so it was either caused by too much clearance or detonation
I have to admire the fact that even the worse destruction you find you manage to take it as a pinch of salt . Been loving watching your vids and you've actually made me fall back in love with dirt bikes, keep up your great work my friend.💪👍
Millenium Technologies can fix/replete the cylinder. You cannot reuse that rod, the crank has to be rebuilt. The rod itself is the pin bearing race and that bearing was shot. You also have debris in the lower bearing no matter how much brake clean you use.
I always put a little extra oil in my mixed gas. A little bit more smoke is way better than forever rebuilding them. 2 strokes don’t need a lot of warm up time, sitting idling is what carbons them up. Even using a little extra oil I’ve never fouled out a spark plug on anything.
Chances are his friend ran it with straight gas but if you git that thing up n runnin it is an absolute ripper!!! I bought the same bike for my Daughter n that thing is a lil monster with power everywhere!!!
Love your videos! I’m guessing the piston clearance was way off. Cylinder is probably worn out and the grey plug is all the piston debris. Don’t believe it was running lean. Measure the cylinder. Good luck!
I never give up on a job no matter how bad it is, in this case I would have gone straight to working on wheeling it down to some guys garage at 2AM ......some guy I just don't like preferably and then sneaking back home. Job done.
You're basing the lean running on the grey coloured spark plug. I would suggest the plug is grey due to the aluminium dust created when the piston failed. Apart from some discolouration of the con rod, there's no other evidence of hot running. The oil appeared to be silver grey too, suggesting it was contaminated by aluminium residue... though how it would get to the gearbox I have no clue! This could be a simple case of piston failure.
@@MusicSensations1971 I seen Joe draining the clean coolant in the vid. Doesn't mean there was coolant when it blew. Maybe the person who did the build forgot. Seen a few come threw Honda service that lost coolant or someone working on forgot to add coolant, to do that kind of damage from heat ♨️ . Just a theory anything can happen, it's 2strokes life lol
Great work Joe, to up your game I would use a brass drift and engineer's ball pein hammer, not the builder's claw hammer and socket extension when tapping out those long bolts. Impressive skillset you have.
Great video, love the relaxing style you create and fixing these classic bikes is really great to watch, you're like the Watch Wes Work of the bike world, superb stuff, subbed and liked.
I hate to be one of those guys tellng you what tools to buy.. but an exhaust spring tool is super nice. I used to use a vice grips as well until i used a spring tool.. night and day. Thanks for the vids n the great narritive you do bud.
Lean on oil and possibly an air leak at a crank seal. Gray on the spark plug was metal deposits. Pressure test after you reassemble to make sure the case and head is sealed.
Since the carburetor was an off brand, the needle clip position may have been in the full rich but the needle itself was not manufactured properly. The end result of the lean condition. That or the carb that ran lean did the damage was removed and a new carb was installed later. It doesn't make a lot of sense to do that to fix the problem but it was too little too late.
I'm a big fan of your channel Joe, but I've never owned a two-stroke dirt bike. Please explain how the power valve works to produce more power Is there some kind of vortex that it creates or does it increase compression as RPM rises? Great video, you can fix it.
Get a real cheap borescope and look down the spark plug hole. Also, pull the pipe off and take a look at the side of the piston. Lots of good stuff you could be looking at before the tear-down!!!
YES! And for Pete's sake start measuring your piston to cylinder wall clearances when you put a bore/hone job on something and just slap in a brand new SeizeCo forged piston!!! 😂😂😂
You should turn it into a big bore KX301cc from Kustom Kraft, that way you might be able to reuse the cylinder. They list the price at $650 and are located in Las Vegas. Good luck.
White plug is a lean, grey is aluminium and oil/fuel mix. I think its called death ash. Piston looks to be la sleeve forged piston. I bet he just forgot to add oil. Cylinder is repairable too, some companies might not provide that service though. You weld with 4043 welding rods, then rebore to size.
Hey Joe, keep up the amazing content, loving these videos. Inspired me to buy and old 2009 Husqvarna SMR 450 to do a rebuild on. It needs a replacement head gasket, cooling system is over pressurising. I will change the piston and rings at the same time, from your experience which piston would be best to go with? Athena, Wossner, Vertex, Pro-X….? Cheers
Hey, nice video. That piston is exploded. They should pay more attention to jetting the carb and the needle position. There are a bunch of sites with jetting setups. Also, I have a suggestion: try not to use PZ bits on Philips screws. Pozidriv (PZ) uses different angles than Philips (PH), and you can easily strip the screw head if you are not careful enough. Some old Japanese bikes use JIS screws which also look like Philips but in the middle, there are sharp corners instead of rounded ones. JIS screws are usually marked with a dot.
Whats strange, is how everything was set to be rich, makes me think they were having problems with it running lean and didn't sort the problem fully, before running it hard.
The damage wasn't likely caused by over heating or wrong oil mix .it looks like to much ring gap it probably rattled its self to death thats why its the intake side bottom piston skirt that took most damage. Looks like detonation was present olso . Probably rebuilt with the wrong size piston to bore clarence new piston and rings into a worn out cylinder usually a combination of a few things which cause a chain reaction once detonation occurs it does not take long to grenade the force generated by detonation are massive probably why the small end bering fell apart in your hands the crankshaft wont be long behind it. Best to replace when you rebuild
Hiya, I run a few strokes and a couple of tuned ones...it .oops exactly as you say. It's run weak and overheated. I didn't see the air cleaner. I would consider doing a crank case pressure test when the crank and seals are in. On my bike the cylinder studs are usually at fault but I've seen many different leaks from porosity to case cracks. As you've nothing definite to see I'd consider it bud.
I wonder if he was running gas with no oil? Also I'm thinking with the plug being gray like that maybe that was metal shavings covering the plug, you know, not that it was lean but just worn down ring got up in there, and I'm thinking the gas may well have been without oil - or the piston just shit the bed and that's how it goes sometimes.
Joe you have been a unlucky and lucky in this project bike is in good condition but definitely running to lean but you will sort it out mate love your content as usual I’ve just blew my water pump seal on my LC so I’ve ordered the parts to repair it and get stuck in to it
@@TroySmith-cz5jy oh, well. I guess we don't count 🤷 the money from half a million TH-cam subscribers watching his channel because he does the tough repairs. Sounds like yall have it all figured out.
Burning that clean can also indicate water in the gas. Might have been burning the water in the gas or cooling system to cause "lean" symptom to occur.
No way of knowing if there was an air leak on a torn down engine if not obvious without performing a leak test prior. It very possible the afr was off. There was oil in the bottom of crank case indicating premix, but who knows what ratio. Not sure what piston kit and wrist pin bearing was installed but the china carb is an indication. I believe the piston grenaded due to too much cylinder wall to piston clearance. A proper measurement using a bore gauge would help determine that. There are many factors that likely contributed to the end result.
Those are suppose to have wet clutch oil in the case also for that bike unless it specifics it otherwise in the rebuild and repair and maintenance manuals as we'll to. I guess is it was the fuel mixture was mixed to lean truthfully for the carburetor set-up on the dirt bike.
Friend probably put cheap gas station, boat 2 stroke oil in bike,off the shelf next to cat food. 2 stroke oil designed to run in cold lake water temps,not hot dirtbikes. Piston started dragging, till skirt fatigued. Might explain gray on sparkplug. Cooked 2 stroke oil, designed for cold water applications ?
My dad had a Kawi dealership back in the 80's and 90's. I saw a ton of these bikes all new and shiny. My brother was the mechanic. You remind me of him . He was considered to be the best bike mechanic in the area for many years, everyone brought there bikes to him if they wanted it fixed right. I did too. When I would tell him about a problem with my bike or ski he always said the same thing. Toys break. I miss those days.
my guess is it had an air leak from a gasket. someone knew it was lean and tried to make it richer but not enough. you need a leak tester for testing 2 strokes.
Hey Joe, Been watching for quite a while...Great content! I was watching some Tik Tok and noticed that a channel called "Kyle Corbett Dirt Bike" has a bunch of yor content on his account. Not sure of your feelings about this...Tough break on this bike with that piston grenading and messing up the cylinder.
That plug may not have been new. If it ran rich from the carb settings, possibly it had a plug that fouled, and another one was put in that had already been run lean previously. That ring gap in the video, when you first showed it, I thought it looked more like a quarter inch!! Blow by could have cooked the piston, if that's true. I had a piston skirt come loose in my old Norton, and fell down in the crank case, due to a hairline crack that developed at the bottom of the oil ring groove.
My guess is with all the four stroke bikes out there these days, at the track someone just poured straight gas in it not knowing about old school 2 strokes and 2 stroke oil.
My thoughts as well.. straight gas ⛽️ then boom… then the realization, “forgot the oil” so before returning blown up, oil was added as well as the “I don’t know what happened”
That's what I thought too.
Time to call LA Sleeve 😬
The fuel didn't look mixed when he tested the petcock.
Ditto, straight gas been run for a period .
I enjoy watching Joe fix these machines, but the one thing about it is that there's no follow-up on what happens to them once they're fixed. It leaves people to assume they're just piling up on Joe's property. I, for one, would be very interested in what happens to them after they're fixed. A breakdown of how much he paid for them plus repair costs and then ultimately the sale of each of them to see if he either made or lost money or if he broke even would be awesome. Does anyone else feel the same way? Thanks! 👍🏻
Me to🇦🇺👍
He does have follow up videos, I think he’s got to wait for the parts to come in and work around the other builds he currently has
me too ! doing some real repaires
Sometimes I wonder what he does for a living,maybe it’s the TH-cam but he has a really nice home. Lol.
My guess is they didn't mix their fuel properly. Was probably really lean on oil.
Less oil = More fuel = Rich / less oil would create a lubrication problem, not a lean condition; I think Joe is right on, was running way too high air to fuel (lean) created a lot of heat and grenaded the piston. My guess is an air leak down stream from the carb.
@@TroyJohansson-l6f Nope, it's lack of oil in the mix. Yea she was running a bit lean(plug) but not enough to cause that damage. It's pure friction damage. AND he said the locked up in mid jump, amateur rider with no throttle control over reved it. typical ricky racer over reving and constant throttle blipping
@@GoofieNewfie69 Your both wrong he checked the fuel it was colored so it had oil. both jets, air screw, and needle were rich especially the needle so an air leak is a bit unlikely the cause.
@@PurpleMonkeyWaffle It had oil, but how much. By looking at a fuel mix tell me how you can tell the difference between 30/1, 40/1, or 50/1. If you had the fuel and oil that was used, mixed them at varying mixtures, you may see the difference. Barring an evaporative or IR test you don't know what was in it when the piston failed. But the key is in the needle bearings. They take a while to wear out like that, not just a minute or so of overheating.
We used to race 2 smokers in the 70's and seen many types of failures, The head shows lean and not enough oil. Pistons grenade like that from overreving, too small for the bore and lack of oil.
Now on the other hand, there may have been enough oil in the fuel by not mixed to a homogeneous state(most people put the fuel and oil in a tank and shake it for a few seconds. We always put 1/4 fuel in tank, added required oil for the mix, shook for about a minute, the added another 1/4 fuel shook repeated till all fuel was in. The oil will separate if not mixed very well. It will look like a lean burn on piston, and plug, but the bearings tell a different story. Then the over reving, now-a-days you don't see it so much with rev limiters. Watch a good rider jump vs a ricky racer. Ricky racers usually wind em out in a jump can even hear the limiter kick in , but not good or pro riders
@@GoofieNewfie69 I would lean more towards the fuel mixture being the issue. That bike was meant to be revved in the higher RPM's compared to the bikes of the 70's. Your 100% right that there is no way of knowing what the fuel mixture is. These days, alot of the 2-stroke oils being sold (atleast quality oil) is the same color as the fuel so it is very possible this was just some person that had no idea that oil needed to be mixed with the fuel and they just threw straight pump gas in the bike.
The gas you pulled out looked pretty clear not much oil
Have you ever run Maxima oils? cant tell its mixed lol
Always replace the crank seals especially when the can't be replaced from the outside. It isn't worth the gamble saying "they look good". This is definitely true when the engine has gotten hot enough to destroy the piston and upper rod bearing.
I was about to type the same thing.. Good call mate.
Not needed if you are just flipping it for profit.
@@Poppinwheeeeellllllieeeeezso your a scumbag
It is needed if you don’t want to get a reputation for flipping shit. Common sense
I'd say they ran the incorrect fuel ratio or straight gas.
I'd also replace the rod and bearings since you're in that far.
My guess is they just grabbed the wrong can of gas.. good work joe, thanks for bringing us along.
Coolant lines look like every garden hose I ever drank from when I was a kid.
each of those fancy green lines added 10 HP
Dont they lol... I thought the same thing. Brought back the 70s for me mate lol
Yes, those definitely need to be replaced with coolant resistant hoses.
They are legit Kawasaki Green lines.
I watch these vids with my jaw dragging along the floor.... As a home wrencher who oh so often reaches the "I'm scared to go any further" point. To watch someone keep going....no matter what, all filmed with the calm logical narration...Superb, compulsive viewing 5⭐ 👏👏👏
unreal the money this kid has to buy all these bikes and atvs and never has to sell nothing!!you tube is great!!
Lmao he sells a lot of the bikes on the channel and buys more to further the content. You really think he’s just fixing these and keeping them? 😂 he has a couple of older videos of what he’s actually kept. Mostly rare or vintage stuff
I always change the top-end bearing with a new piston, they're kinda fragile. Wauw that piston grenaded. Sorry for you for having to rebuild, but once again a great video. Big Up!
Yes you dont save 15 dollar on that bearing if you change piston.
Thank you thank you, 2vintage! Your channel inspired and motivated me to buy a 1997 Kawasaki KX250 and work on it myself. Getting it running and ripping has been extremely rewarding. You rock!
So much suspense building since you are checking the top end LAST!! 😅
You'd think these jobs would be hard enough without taking off everything everyone already knows isn't the problem.
I’ve been away so catching up on your videos.
This really looks like it’s been run without 2 stroke oil.
But I think you got lucky with it. That kind of failure generally ends up with cracked cases.
Looking forward to the next one on this bike.
I just bought a 1994 yamaha xt350 and the seller said he was rising and it lost compression. He said he installed a new piston and timing chain and still no compression so I got it for $450, got it home and this thing has stripped cam bolts and broke bolts on exhaust. Has 2 bent valves,original piston original timing chain, and bad wrist pin on the rod side. Loving the honesty. ❤
Great watching you strip down the 1996 kX 250, looking forward to watching you rebuild it, wish you lived near me, my 89 cr 125 hasn't been fired up since 93 ( walsall England )
every video of yours I pray for a difficult one for 2 reasons:
1 - is what makes me watching
2 - because I know you can solve it
Wonderful isnt it? Kids got some skills, thats for sure. Has helped me a Lo9t already, been watching him since he had like 20k subs. I always learn Something from is videos, worst case its same thing but Drills the problem solving steps in for good and others a Whole new can o worms :) Cheers.
That is not caused by overheating I made my first comment before the cylinder was pulled off and that looks to be like too much clearance banshees are bad for doing that if you have too much clearance they'll break a piston skirt on the intake side so being that the exhaust side isn't all messed up that wasn't caused by overheating It's either detonation cause the piston to break which it can do or there was too much clearance for the piston and it just rattled back and forth till it broke the skirt The reason it'll break on the intake side if it's too much clearance is because that's the on the upstroke for its compression stroke that's the stress side of the piston that's the side of the piston that all the pressure is put on as the rod transitions to going back up there's always a little bit of side load on the skirt so it was either caused by too much clearance or detonation
I have to admire the fact that even the worse destruction you find you manage to take it as a pinch of salt . Been loving watching your vids and you've actually made me fall back in love with dirt bikes, keep up your great work my friend.💪👍
This is why when my nephew called to borrow my six month old two-stroke, to ride an illegal spot with his idiot friends, he got laughed at.
because the cylinder was roached? or because you figured he would?
I read some comments, i like the idea of straight gas in the tank. my first thought was crap carb, leaned out and killed a fresh motor.
I dont even ride dirt bikes anymore & I love these videos. you do a great job, thanks.
Now I’m leaning towards the crank sounds pretty deep when you rock it back-and-forth.
Millenium Technologies can fix/replete the cylinder.
You cannot reuse that rod, the crank has to be rebuilt. The rod itself is the pin bearing race and that bearing was shot. You also have debris in the lower bearing no matter how much brake clean you use.
Hopefully he listen to you but doubtful he will.
Comon man this is joe dirt channel no way he gonna fix it right
He wont listen lol
He's in Wisconsin where millennium tech is.. he knows 🙄.
@@thyreaper650 let him spend 600 instead of 300
You are the doctor.. love what you do.
I always put a little extra oil in my mixed gas. A little bit more smoke is way better than forever rebuilding them. 2 strokes don’t need a lot of warm up time, sitting idling is what carbons them up. Even using a little extra oil I’ve never fouled out a spark plug on anything.
More oil means less gas through the jet that makes a lean mixture
That sound off sand from the gloves when he hold the crank make me twist. You do a great job But plz listen to the 5000 comments wash Your engine’s
Lol...
Chances are his friend ran it with straight gas but if you git that thing up n runnin it is an absolute ripper!!! I bought the same bike for my Daughter n that thing is a lil monster with power everywhere!!!
I don’t think you’ve ever lucked out with a “lock up”; but great content for us 👍
Love your videos! I’m guessing the piston clearance was way off. Cylinder is probably worn out and the grey plug is all the piston debris. Don’t believe it was running lean. Measure the cylinder. Good luck!
100% not mixed fuel !
Shame , the KX 250 is a lovely bike.
Be hard to source a cylinder for that for a good price.
I think the seller ran straight gas through it, then put mix in it, only way i could come up with
Put mix in out of pure shame 🤣🤣
Mate while engines out tidy up the frame just with rattle-can blow it all in
I never give up on a job no matter how bad it is, in this case I would have gone straight to working on wheeling it down to some guys garage at 2AM ......some guy I just don't like preferably and then sneaking back home. Job done.
Great work you do and great video. Once you get that top end corrected with new parts should be a sharp running Kawasaki 250 !
I would send the cylinder to Powerseal USA for $254 plus shipping both ways and get it fixed right. No sleeve and no buying a $650 cylinder off ebay.
This is the only mechanical series I never fast forward, thanks for the great Contant, my friend
I have seen to many times where a bike is not warmed up enough and get the famous cold seize..Very important to do.
Yes I always warm my yz125 2003 an run 25.1 gas mix
My brother had a vertex fail like that in his yz 250 at 40 to1 all the factory jetting and stock pipe
Usually with a lean seizure you would get lot of metal scooped out of the piston crown, My guess would be someone put straight gas in it.
You're basing the lean running on the grey coloured spark plug. I would suggest the plug is grey due to the aluminium dust created when the piston failed. Apart from some discolouration of the con rod, there's no other evidence of hot running. The oil appeared to be silver grey too, suggesting it was contaminated by aluminium residue... though how it would get to the gearbox I have no clue! This could be a simple case of piston failure.
grey is the colour for oil after been used in a wet clutch
@@empiresrikesfat you need to change your oil more often!😆
I wonder if somebody put straight gas in it before they rode it ?
I wonder
That !?! or it was running without coolant lol. Who knows 🤔💯
@@just4kicks950 no I seen the coolant be drain there was coolant in it
@@MusicSensations1971 I seen Joe draining the clean coolant in the vid. Doesn't mean there was coolant when it blew. Maybe the person who did the build forgot. Seen a few come threw Honda service that lost coolant or someone working on forgot to add coolant, to do that kind of damage from heat ♨️ . Just a theory anything can happen, it's 2strokes life lol
Great work Joe, to up your game I would use a brass drift and engineer's ball pein hammer, not the builder's claw hammer and socket extension when tapping out those long bolts. Impressive skillset you have.
Great video, love the relaxing style you create and fixing these classic bikes is really great to watch, you're like the Watch Wes Work of the bike world, superb stuff, subbed and liked.
I hate to be one of those guys tellng you what tools to buy.. but an exhaust spring tool is super nice. I used to use a vice grips as well until i used a spring tool.. night and day. Thanks for the vids n the great narritive you do bud.
Either fuel mix or possibly an air leak from the crank seal or intake boot, I've seen the crank seals leak on the older 2 strokes quite a bit.
The grey plug would tell
Me pri detonation .. woodruff key went and timing got way advanced.
Bro, engine teardown and rebuild videos are my ASMR
Lean on oil and possibly an air leak at a crank seal. Gray on the spark plug was metal deposits. Pressure test after you reassemble to make sure the case and head is sealed.
"Hear that" - when you know something is seriously messed up and it's going to cost money 🤣🤣🤣
Hahaha
Where'd you get it bud😮😅😊 0:26 @@2vintage
Since the carburetor was an off brand, the needle clip position may have been in the full rich but the needle itself was not manufactured properly. The end result of the lean condition. That or the carb that ran lean did the damage was removed and a new carb was installed later. It doesn't make a lot of sense to do that to fix the problem but it was too little too late.
You Sir have an amazing knowledge of multiple bikes
I'm a big fan of your channel Joe, but I've never owned a two-stroke dirt bike. Please explain how the power valve works to produce more power
Is there some kind of vortex that it creates or does it increase compression as RPM rises? Great video, you can fix it.
Get a real cheap borescope and look down the spark plug hole. Also, pull the pipe off and take a look at the side of the piston. Lots of good stuff you could be looking at before the tear-down!!!
And remove carb and Reed cage to look at piston
YES! And for Pete's sake start measuring your piston to cylinder wall clearances when you put a bore/hone job on something and just slap in a brand new SeizeCo forged piston!!! 😂😂😂
You should turn it into a big bore KX301cc from Kustom Kraft, that way you might be able to reuse the cylinder. They list the price at $650 and are located in Las Vegas. Good luck.
Wow that thing was super detonating I bet you could probably hear the pinging in the engine it had to be so severe
White plug is a lean, grey is aluminium and oil/fuel mix. I think its called death ash. Piston looks to be la sleeve forged piston. I bet he just forgot to add oil. Cylinder is repairable too, some companies might not provide that service though. You weld with 4043 welding rods, then rebore to size.
I had a 96' KX125 Split Fire addition! It was a sexy bike!!
Vinny didn't do a pre-inspection before buying!
Hey Joe, keep up the amazing content, loving these videos. Inspired me to buy and old 2009 Husqvarna SMR 450 to do a rebuild on. It needs a replacement head gasket, cooling system is over pressurising. I will change the piston and rings at the same time, from your experience which piston would be best to go with? Athena, Wossner, Vertex, Pro-X….? Cheers
Hey, nice video. That piston is exploded. They should pay more attention to jetting the carb and the needle position. There are a bunch of sites with jetting setups.
Also, I have a suggestion: try not to use PZ bits on Philips screws. Pozidriv (PZ) uses different angles than Philips (PH), and you can easily strip the screw head if you are not careful enough. Some old Japanese bikes use JIS screws which also look like Philips but in the middle, there are sharp corners instead of rounded ones. JIS screws are usually marked with a dot.
As soon as you pulled the cylinder off and saw that piston I was speechless.
Whats strange, is how everything was set to be rich, makes me think they were having problems with it running lean and didn't sort the problem fully, before running it hard.
I would be tempted to change that filter in the fuel filler cap too seen them fail before
Did the same with a vespa was ringing its neck for ages hope u get it sorted 👍
Yep. My guess also. Straight gas was put in the bike toasted crank
Bro your text tone has been the same for so long 😂 I respect it
That’s crazy. If you ever do merch, put me down for a “That’s Crazy” t-shirt.
"Looks Perfect !!" I'd buy some of his merch, as well. Hoodies.
Wrong oil gas mix blow this engine up for sure.
Keep up the good videos 👍
The damage wasn't likely caused by over heating or wrong oil mix .it looks like to much ring gap it probably rattled its self to death thats why its the intake side bottom piston skirt that took most damage. Looks like detonation was present olso . Probably rebuilt with the wrong size piston to bore clarence new piston and rings into a worn out cylinder usually a combination of a few things which cause a chain reaction once detonation occurs it does not take long to grenade the force generated by detonation are massive probably why the small end bering fell apart in your hands the crankshaft wont be long behind it. Best to replace when you rebuild
Hiya, I run a few strokes and a couple of tuned ones...it .oops exactly as you say. It's run weak and overheated. I didn't see the air cleaner. I would consider doing a crank case pressure test when the crank and seals are in. On my bike the cylinder studs are usually at fault but I've seen many different leaks from porosity to case cracks. As you've nothing definite to see I'd consider it bud.
I wonder if he was running gas with no oil? Also I'm thinking with the plug being gray like that maybe that was metal shavings covering the plug, you know, not that it was lean but just worn down ring got up in there, and I'm thinking the gas may well have been without oil - or the piston just shit the bed and that's how it goes sometimes.
Joe you have been a unlucky and lucky in this project bike is in good condition but definitely running to lean but you will sort it out mate love your content as usual I’ve just blew my water pump seal on my LC so I’ve ordered the parts to repair it and get stuck in to it
I do Joe set that clip in the middle for the slide and the fuel is 40:1 mixture.
$ 1,200 purchase. $400 cylinder repair, $300 crank assembly, $160 piston kit, $ 40 gasket kit. I'd say your profit is gone on this already. 😢
Pretty close my area they still bring 2200-2500
@@TroySmith-cz5jy oh, well. I guess we don't count 🤷 the money from half a million TH-cam subscribers watching his channel because he does the tough repairs. Sounds like yall have it all figured out.
They're $2500 in good condition. This bikes had a rough life. It'd be $2k running where i live.
I'd guess the bore was out of round an the ole piston slap got it.
Burning that clean can also indicate water in the gas. Might have been burning the water in the gas or cooling system to cause "lean" symptom to occur.
You could say that the piston is half gone or better yet, the piston is half there. 😮
No way of knowing if there was an air leak on a torn down engine if not obvious without performing a leak test prior. It very possible the afr was off. There was oil in the bottom of crank case indicating premix, but who knows what ratio. Not sure what piston kit and wrist pin bearing was installed but the china carb is an indication. I believe the piston grenaded due to too much cylinder wall to piston clearance. A proper measurement using a bore gauge would help determine that. There are many factors that likely contributed to the end result.
😮i would check the rod end at the piston to make sure it is in speck , so you dont end up with a loose wrist pin at the piston
Look into the exhaust port and look at the piston
Those are suppose to have wet clutch oil in the case also for that bike unless it specifics it otherwise in the rebuild and repair and maintenance manuals as we'll to. I guess is it was the fuel mixture was mixed to lean truthfully for the carburetor set-up on the dirt bike.
That is pretty lucky those cases didn’t crack man! Wow!
Great video. Great close ups. Thanks.
Those knockoff Keihn pwk carbs are usually pretty good actually
@@JoeTheBlacksmith13 Yes, I had a good experience with using one but I replaced both the Jets and the needle.
Get a bore gauge and a micrometer and check the size of that cylinder. Maybe its the wrong size piston, too big probably causing too much friction
Probably was at a party and reving it red hot burning rubber red hot pipe ect until it broke. Put a new back tire in and sold it
Friend probably put cheap gas station, boat 2 stroke oil in bike,off the shelf next to cat food.
2 stroke oil designed to run in cold lake water temps,not hot dirtbikes.
Piston started dragging, till skirt fatigued.
Might explain gray on sparkplug. Cooked 2 stroke oil, designed for cold water applications ?
When taking foreign material out of an engine always check it for magnetism. Knowing its magnetic is good info.
My dad had a Kawi dealership back in the 80's and 90's. I saw a ton of these bikes all new and shiny. My brother was the mechanic. You remind me of him . He was considered to be the best bike mechanic in the area for many years, everyone brought there bikes to him if they wanted it fixed right. I did too. When I would tell him about a problem with my bike or ski he always said the same thing. Toys break. I miss those days.
Check the float height, that can affect the amount of fuel going up the main jet.
Damn Joe a Greyhound bus can drive through that piston ring Gap !
I have a mint KX 250 love it bored out and rapid pal loads o power
Sweet bike Joe, save her!!!
my guess is it had an air leak from a gasket. someone knew it was lean and tried to make it richer but not enough. you need a leak tester for testing 2 strokes.
Ive replaced the crank and piston in this exact same bike. Its a fist full of power when done and dead wallet even when getting the cheapest
Good looking bike, ARGH frustrating putting someone else's puzzle back together
Hey Joe, Been watching for quite a while...Great content! I was watching some Tik Tok and noticed that a channel called "Kyle Corbett Dirt Bike" has a bunch of yor content on his account. Not sure of your feelings about this...Tough break on this bike with that piston grenading and messing up the cylinder.
Maybe hit up L. A. Sleeve, the kit is a decent price and they have an option to send in the cylinder to have them install it.
Did you check the fuel mix in the tank? Straight gas. Everything else checks out
That plug may not have been new. If it ran rich from the carb settings, possibly it had a plug that fouled, and another one was put in that had already been run lean previously. That ring gap in the video, when you first showed it, I thought it looked more like a quarter inch!! Blow by could have cooked the piston, if that's true. I had a piston skirt come loose in my old Norton, and fell down in the crank case, due to a hairline crack that developed at the bottom of the oil ring groove.