Top and Bottom build

[Robert Waller]

getting low compression (70psi)
pulled the cylinder to find piston skirts completely broken off. what could’ve caused this? i’ve only had it for 2 weeks and it’s been running sh*tty since i got it. anyway time for a top end build and since there’s metal frags in the case the bottom too. cylinder and head are at the machine shop i’m waiting to order piston, rings, wrist pin and bearing. crank has no up and down play. ordered a full seals kit and crank bearings. also got new clutch plates and springs. any advice on taking this on? the top end seems very easy and the bottom seems easy too but looks like there’s a lot more room for error. are there any other parts i’m missing that i should replace?

 

[Slydog]

The piston skirts ussualy break due to excessive piston to cylinder wall clearance.
Forged pistons don't drop the skirts like a cast piston.
They are easy to work on. Grab a clymers manual and dig in
These split from the clutch side

 

[Larry's Shee]

Get the lock tab washer for clutch and crank

 

[Robert Waller]

Get the lock tab washer for clutch and crank

thanks, do i need that just for doing the clutch or do i need one when i split the crank case too? and if i need it for both are they the same?

 

[Slydog]

thanks, do i need that just for doing the clutch or do i need one when i split the crank case too? and if i need it for both are they the same?

Get one for each like mentioned. As they are different. They are not recommended for reuse. Bad things will happen if one of those nuts come off

Dont forget to get some yamabond 4 to reseal between case's