88mm piston in a 300ex

[kxrider]

friend just got a 300 need new head and piston, so we order new stock one and its to small, ,and the dude says he need a 88mm, ,but i see that the 400 is only 89???? how cna this be or can it someon tell me, and tell me were to findd one i searched everwere

[mikeboone]

You wont ever get a 88mm to fit a 300ex. Stock 300ex bore is 74mm. Stock 400ex is 85mm and the 88mm bore is a 426 on the 400ex.

[kxrider]

thanks man thats wat i tryed to say, btu now he is sayin just 80 so how about that were can i find that, or is it possible

[mikeboone]

Yea, you can get a 80mm although the cylinder will need to be sleeved. The 80mm with stock stroke would give you 330 cc's. Check with CT racing or Sparks racing for their 330 kit.