So I’ve had this bike 6 years and it had a full rebuild when I got it and I verified but this past couple years it has sat a while because the water pump failed and I was broke and never fixed it but eventually I did and broke a side case cover bolt right next to where one was already broke off. I already tried tapping it and extracting, I put the side case cover back on and checked nothing was leaking so I rode and sure enough oil leaked out while I was riding and the bike killed itself, it felt locked up but I gave it a good kick and it broke free. So I pulled it apart to check it out and my water pump gear broke off in one perfect chunck and I eventually fixed that and tapped one of those broken bolts out, so I decided after that abuse I should probably do a top end, so I do just that and noticed middle intake valve was tight as could be and was shimmed out. Instead of doing a valve job like I should’ve I just bought a used head and checked clearance and slapped it on, upon breaking new oem piston in and everything I noticed my bike would run smooth as a whistle and always first or second kick now but when it got hot it would die out of nowhere super hard almost like it was under strain and I noticed milky oil so I checked head gaskets and replaced and then I realized water pump seals were backwards lol, but I thought that milky oil was causing the engine to die weird like it was but after I fixed that and triple checked timing and clearances were good it’s still doing it. When it dies like that the kickstarter feels as if the bike is locked up like before but one good kick with free it up and it will start back up but do the same shit, I’m super lost.
2008 yz250f weird problem need help
- Thread starter ashtongoff012
- Start date
Howdy.
I suspect the bottom end/crank bearings are the problem.
-The condition and quantitiy of oil has varied wildly while in use.
-Broken engine parts in the oil.
-The engine locking up and unlocking.
These signs following an oil issue is usually not good.
Some bearing is giving you trouble and it'll probably be discolored.
I'd take the top end off, and get the crank spinning freely from the clutch and see if it binds at all.
Does the clutch shaft spin freely?
Main clutch shaft bearing also would be good to inspect.
-BIG DAN
I suspect the bottom end/crank bearings are the problem.
-The condition and quantitiy of oil has varied wildly while in use.
-Broken engine parts in the oil.
-The engine locking up and unlocking.
These signs following an oil issue is usually not good.
Some bearing is giving you trouble and it'll probably be discolored.
I'd take the top end off, and get the crank spinning freely from the clutch and see if it binds at all.
Does the clutch shaft spin freely?
Main clutch shaft bearing also would be good to inspect.
-BIG DAN