I just bought a 2001 400ex for $450 dollars. The engine needs to rebuilt. I was thinking about just replacing the engine as was wondering if anyone knew where i could get a one and about how much it will be. The engine has been bored out and has a 11:1piston . If i just replaced the upper end I'd still hav to bore it out again or buy a stock piston. Would it be more than 500? thanks

 

I might be reading this wrong, but, If you have to bore it out, and it is already bored, then you can't use a stock piston..its too small..

 

the one i have is bored out. If i bought a new upper end it would be the stock bore that means i would have to bore it out to work with the 11:1 piston if I did'nt bore it out i would just have to buy a stock piston. That was a little confusing i guess.

 

i have a stock piston if your interested.

 

Complete 400ex engine on Ebay for $600