New here - looking for top end pointers - please!

[JimM]

Thank you again.
Now I just need a block of time to do the job....

[Thumprding]

Here is a little trick I learned a while ago that makes putting the cylinder back over the piston easier.

What is going to happen is that you are holding the piston with one hand while squeezing the rings and then with the other hand trying to slip the cylinder over the pinched rings. Sort of tricky to do by your self.

The trick?
Take a piece of plywood about 3 inches wide and about 8 to 10 " long and cut a groove in it as wide as the connecting rod. Start in the middle and cut it cross ways about half way thru. Now pull the piston up, slip the board between the piston and the case. Push the piston back down until the skirt sits on the board.

Now the piston will not move down and is stable while you pinch the rings and slip the cylinder over the piston. Once the you have the cylinder over the piston and both rings, hold the piston by the skirt and gently lift it and the cylinder up. Pull the board out then lower the cylinder down on to the case.

No this will not hurt the base gasket.

[ossagp]

Or use a "rag". Do a few and they seem to just fall on. Clymer manuals all run the pic of the "wood" though.

[weebles]

I have a question how would I find out if my head needs to be honed or I think its called up sizeing

[Dan151]

[Only registered and activated users can see links. ]

this should help you, great video on how to rebuild a yz250 top end. i just did the top on my yz125, the guys here were MORE then helpful