Rebuilding What are the piston sizes

[thegoodkidwhomightlikebanshees]

What signs to look for as to know when you need a rebuild?

 

What are all the piston sizes?

 

I think the first is like zero and then 25 and then 50 and then 75?

[ogre03]

If you aren't rebuilding because of a problem, that the best way to tell if you need to is a compression test. Guages are cheap, but make sure you get one with the threaded end. Pistons can be refered to as how many thousandths over (like mine is 20 thousandths over) or in MM. like 50mm. the mm is what you are talking about.

[thegoodkidwhomightlikebanshees]

I mean shall I look for the following signs in order to go for a bigger piston size:

 

1. alot of smoke coming out ?

 

2. reduction in performance ?

 

3. what else ?

[iceman]

low compression. you generally rebuild when your compression is low. if youve got good compression and youre losing power the problem is probably elswhere.

[Wallrat]

Performance could decrease. It might be hard to start. But the only sure-fire way to determine if the problem is worn rings is to use a compression tester. There's a ton of other stuff that could cause the same symptoms as a worn top end.