help needed?????

[400ex18]

Ok heres the deal Im tryin to get my 250r rebuilted and everthing was going smoth, then tryed to kick it over and it wont!! Soo i figured out that my piston is to tall and is hitting my head!!! what can i do im lost!! i bored it 80 over witch is a 68 mm piston!! so why is my piston to tall could it be a defect??? PLEASE HELP Thanks!!

[garrettagr]

is the motor an 86 or 88-89? could be that you got the wrong year piston for your motor. Not quite sure if that is what it is or might be, i may be totally wrong but it is a thought.

[400ex18]

is there a difference between the 86 and 87 250r pistons?? cause i think the motor had a 87 piston in it!!

[Fear250r]

Yes, there is a difference. If the motor had an '87 piston in it and you're using an '86 piston, you'll need to either get the spacer plate or another piston.

[400ex18]

so if i get a 87 piston 68mm it will work then.

[Fear250r]

Yes, that would fix it, but if you already have an '86 piston, you could spend less and get the spacer plate. I'm not sure how to check, but I would make sure what you have is a '87-'89 cylinder.