questions

[Arynock]

what are some few things i can do to my stock 400ex to get some power to it? and what do all these do?

i was wondering what difference a front 16t sprocket would have on a stock motor?

[Bill Fuller]

A stock motor will have alot of trouble "pulling" a 16 tooth sprocket.Most people put a 14 tooth sproket on to increase the the pull off the bottom.In my opinion the 15 is fine.You never said what kind of budget you are on.If you don't want to spend much than I would take the pipe off and clean up the inside,change the air filter and rejet.You can remove the choke for better flow also.There is alot of info on this site about this same question,do a search.If money is no problem than the sky and your imagination are your only limits.There are a number of performance upgrades you can choose from.....pistons,cams,pipes,bigger carb etc...

[Arynock]

well, how much low end will a 14t front sprocket give ya, i dont want to lose all my topend... i have the problem where when switching into 2nd gear, the front end likes to raise up, i only weigh like 120 :P

[wilkin250r]

Your budget determines alot of what you can do. A slip-on pipe is fairly inexpensive, and will give you a modest increase in power.


If you are mechanically inclined, you can get a high-compression piston and cam and install them yourself. Motor modifications get both more complicated and more expensive, but you can get HUGE performance increases. The high-compression piston will give you more power everywhere. It's kind of difficult to explain how the cam works, but it will basically shift your power, giving you less low-end power and more top-end power.