I have a 2000 Honda 400EX and have already put a 14 tooth counter sprocket, and a motion pro twist throttle. What can i do to show significant power increase for about 100-150$?

 

maybe a used pipe.

 

K&N Filter - $40 or so
Splitfire plug

Cams run about $150 or so( not sure on the 400) but then if you cant put it in yourself you would need to pay someone to. And if you got a cam you would also need Valve Springs and Retainers.

Thats about all I can come up with..

 

Simple. Get yourself a JE 11.1 compressoin stock piston.

 

How much is the piston? I plan on boring it as soon as i get my job, or turn 18 and cash some savings bonds. Where can i get a 11.1 piston and what does it do? I am very new o mechanics.

 

Boring the cylinder is said to make the machine less reliable. also boring means you'll have a bigger piston which means more weight while if you keep stock bore you won't have as much weight. Therefore when you keep stock bore higher RPM's which means more top end. Any ATV magazine will tell you where you could find accessories including a piston. A different piston will higher compression and produce more power.

 

Call CT Racing and get a lightened Ross Racing piston with 11:1 compression. Just get the stock bore size which would be 85mm. I have this piston in my 400EX and i made a big difference in power.

 

I heard a K&N Power Kit makes quite a difference. I am puttin one on my bike, and maybe a pipe. not sure yet which one. power kits run @ 130 in the U.S.

 

If you get the K&N beware of jetting it right. I put one on my trike and melted a piston cause it wasn't right!

 

Forget the filter and jet kits, they're a waste of time and money.

The best bang for the buck in the $150 range is going to be a high compression piston. Get the stock size unless you have to bore due to cylinder wear/damage. Then jet the bike in correctly with Keihin jets, they are much cheaper than a "jet kit" and work every bit as well or better.

A JE piston, rings, and wristpin will run you approx $130 and can be ordered from a number of sources including JE themselves. A top end gasket kit will run you approx $25. A Wiseco piston will be cheaper & can be ordered from a number of places as well.