Mods

[thor_racing123]

This are the mods I plan on doing to the trx 400, hmf full exhaust, hot cams stage 1, rev max rev box, uni air filter, air box lid removed, and some jetting. The hmf pipe comes with the recommended jet for the pipe. Will this jet work with all the other mods I'm adding too? What jets do you recommend? Whats the difference between stage 1 and stage 2 cams? Will these mods make my trx 400 fly? Thanks

[drag93ex]

im runnin fmf powerbomb headpipe with hmf slip on, no box lid, stage 1 cam, aftermarket rev box, and k&n filter. i have dynojet 155 main and 40 pilot, 2 1/4 turns on the air/fuel screw.

[JimmyHoffa]

I'd just start a little richer on the main than the HMF jetting is. Maybe 2 steps higher than the HMF jet, due to your intended lack of an airbox lid and your cam. Bump the pilot up to a 42 also. (stock is 40, I think)

"Stage 1" and "Stage 2" both increase top end and midrange power, but the Stage 2 is applicable to some big bores and offers even more top end power. I'd rather they gave me lift and duration measurements than confuse me with "stages". Oh well.

-Jim

[j450rking]

sound good and like JimmyHoffa said just bump the main 2 steps over what hmf gives you and it should be close and the ex comes with a 38 pilot just so you know not a 40 unless it's diferent for the newer ones and if you look in some mags like moto sport they tell you what the lift is i think the stage 1 gives more lift and less duration and the stage 2 gives you less lift and more duration so there for the stage 1 has more lowend and less top and the stage 2 has more top end and less bottom i don't know what the numbers are so i could't tell you that but i know thats how they are

[Eviltanker]

Nah, still a 38 from factory.

[trx400EXtreme]

Originally posted by drag93ex
im runnin fmf powerbomb headpipe with hmf slip on, no box lid, stage 1 cam, aftermarket rev box, and k&n filter. i have dynojet 155 main and 40 pilot, 2 1/4 turns on the air/fuel screw.
how do u like the cam? good power gains throughout?

[JimmyHoffa]

if drag39's bike is dialed, don't listen to me. The cam may have untold effects on jetting I'm not experienced enough to predict. I only have a pipe, and my ride is running a 165 main. I even keep my lid on and I don't have a filter. Start rich, play around.