400ex stock header modification

[key4202003]

yeah i know i should save some scratch and buy aftermarket, but triplesec is expensive. has ne1 felt any kind of noticable gains threwout the power band. ima gonna doit anyways but thought id ask for technique and were to grind. so far i have ground the weld down level to pipe, but if i was to take the "step up onto level" part that is the peice after the actual flange and make a gradual "funnel" shape to the header.... well waddya tink?? also ya think i will have to rejet? note: i really like the fact that if you take the disks out of the white bros e-series, its just as good as fine tuning yer exzuast...:cool:

[RiderTRX400ex]

i did it, just ground the welds down even with the header, found a little more mid range hit..

[nosliw]

probably going to want to up the pilot jet to a 42 if you already havent

[meanyellow03ex]

Just did this myself on mine. Haven't ridden it since. Mine did have some pretty good weld slop in the pipes. One side was really bad. For a stockish machine, I think the stock headpipe with the ground welds is fine. If you think about it, there is one pipe for each valve, where a 450r has one pipe for two valves.

[key4202003]

muchas grassyass por el infomationio amigos

[bonified5]

**gracias**