Ok, If I switched my stock piston out for the Polaris 400 ATV .060 Wiseco Piston, what would that do to my bike, power?, give me all the pro's and cons., I also saw .020, and .040. Which is better? How hard is the engin work?

 

dont bother going that big of a bore unless you need it..if you want power get some port work and head work done and bore it .020 over add the wiseco piston.the engine is real easy to work on,just get a manual to help ya through it..

 

Power-wise, you won't even notice the difference between going .040 or .060 over. I recommend going as small oversize as you can, to leave more cylinder wall thickness. If you need more power, try shaving the head, porting, and a clutch kit. If you want to go overbore for power, get a true big-bore kit, like the 414 or 440 kits that are out there.

 

real easy to work on. just need a manual and a torque wrench. yea start with 20 over and mill the head, and clutch work!!!!

 

I am interested in getting a used 400 2 cycle scrammy and stripping it down for drag racing only and retire my kawasaki 650 prairie back to the farm bike... Does any one know any specialists on these 400 engines that sell performance enhancements or any good books for 2 cycle hi performance engine building , Thanks for your time, Jim @ jhmachineshop central indiana

 

hpd,rcr rick ritter(rcr) has the best customer service in the buisness,i recomend him[img]i/expressions/face-icon-small-smile.gif[/img]

 

the one wich fit best is the .020 over size,just a little throttle reponse and no top end loss.

 

Thanks the wayout 420 I am pretty serious about one of these bikes they fly stripped down and built with a bottle of nos. thanks again J.H. c.e.o JHMACHINE CO.

 

check out nicholas cycle they have one of the fastes 400's around its literally unstoppable