head pipe

[Jcbowhunter]

i have read some sig's on here and some say drilled headpipe and i was wondering what that means and what you can do to a stock head pipe to build more power.

[CJM]

Take your header off, take a die grinder, large drill bit, etc and drill out about 1" inside. You will see its rather restrictive.

[Jcbowhunter]

are there restricters built into the headpipe?

[kt1148]

Here's a good write-up on grinding the header welds:http://www.exriders.com/vbb/showthread.php?s=&threadid=445008&highlight=header+welds I took mine off and a friend took his die grinder to them, turned out real good.

[Stickman400]

Originally posted by Jcbowhunter
are there restricters built into the headpipe? They aren't really restrictors. They're just crappy welds that Honda puts on them from the factory. You're just grinding off excess weld from the factory so air can flow through better.

[Drfat400ex]

I did it to myn and it turned out good. Better response, a tad louder and if I had to guess I'd say around a half hp gain.

[Jcbowhunter]

ok, thanks guys.