upgrading questions

[big diggin7]

i am going to put a big bore kit in my 01 400ex, what is better, 440, 426, or 416, im looking for relieability, and still lotysa power....also what is the best brand to buy?

[RiderTRX400ex]

the most reliable would be the 416... ive heard they make great power and u can use the stock sleeve without problems

powroll.com has a kit, with J.E piston 10.8:1

im thinknin about that

[big diggin7]

i assume with the 416 kit you haveto bore the engine rite?

[400exstud]

yup, as with all increases in displacement.