straight pipe

[Jared Hamilton]

i built a straight pipe for my 400ex ,but ny cousin told me it would burn up the valves. is this true??(he rides a 2-stroke though)
thanks

[sloppyjoe]

i think it could bend a valve, but its gonna run like crap. a four stroke needs back pressure to run right.

[crazyatvn]

I would not do it not a good idea if you don't mess your bike up you can use the money you saved not buying a pipe and get a good set of hearing aids.

[K_Fulk]

It wont hurt anything. But it will be earsplitting loud, and run like crap ( no bottom end).


Why build a strait pipe? When you could just take the silencer off.

[400exrider707]

It wont hurt anything at all except your power. Not a good idea. Best bet is to keep it stock until you can afford a good aftermarket one.

[nosliw]

Originally posted by sloppyjoe
i think it could bend a valve

how? i've heard of that before but never really understood how it could happen....

[rsimmons_82]

i think he ment that if the head pipe was off, it might warp a valve. (from the instant heating and cooling of the valve)

[Jared Hamilton]

thank, i will probably save money and go with a power core 4

[Jared Hamilton]

i was told too much of a err and no back pressure will bend the valves, it does sound mean as hell tho

[troutman561]

power core 4 is a good choise, i have it on mine and it made mine quicker all around than my friends 400ex with the white bros on it, and it sounds a hell of alot better