400ex question

[400EXcrazy]

i was wondering should i get a wiseco piston stock bore or get a 440 kit with a hot cam and if i do i want a diferent front and rear sprocket i want top end power so what size sprocket should i get. my mods so far are just a white bros r-4 , jet kit and k&n air filter

Your lookin at ALOT more money for the 440 than the stock bore wiesco. If your on a budget like most of us and want decent power go with the stock bore 11:1 look into a JE or Ross piston. Some of wisecos readings are off.

[cals400ex]

yep, i agree. i have a 406 with a ross piston and i like it. i am not sure if i wish i would have stayed with the stock bore or not. i recommend doing the stock bore, 406 or 416 for you. with the 440, you need to buy a sleeve and also get it bored and installed. for the 406 and 416 you will still need to get the stock cylinder bored. if you stay with the stock bore, make sure you hone the cylinder out. i say go with the ross or je piston also.

a larger front sprocket and a smaller rear sprocket will give more top speed. i would say either get a 16 tooth front or a 36 tooth rear. the stock gearing is 15/38. make sure your bike is jetted correctly. that will make a difference in power. also, make sure you don't have 1/2 inch or more play in your throttle lever. you should have anywhere from about 1/8 to 1/4 inch of play. if you have more, adjust it up on the bars.

[Colby@C&DRacing]

If your motor is pretty new and fresh then I would start with a high compression piston and a cam on the stock bore, if not then I would go to a 406 or 416 and I would use the JE or Ross piston.

[400EXcrazy]

whats the stock front and rear sprocket size

[JOEX]

Originally posted by 400EXcrazy
whats the stock front and rear sprocket size
Front = 15
Rear = 38