ok my friend has a 04 honda foreman 4x4 450s. his bike has triangle snorkel kit hmf pipe and a uni filter. he is all the way down on the needle with one washer i think and is using a stock 135 jet. heres the problem..it seems like in 1,2,3 like the power is great, tourqe great, just pulling incredible but up in the higher gears in higher rpm it seems like all that power is not there. almost like it is starving for that power that it has in lower gears. i have a 05 eiger hmf uni dyno 122 jet and no snorkel and he rode it a said he could feel my pulling up there but not on his. any body with his same set up......which jet? which needle setting? any suggestions?

 

If he only has the stock main jet, then id bet thats the problem. I would think it needs to be at least plus 2 on the main(140).

 

I run a 02' foreman 450ES with a penland pipe,triangle snorkel kit and twin air air filter.If he's running a oem(honda not dyno jet) 135 main jet than that is 1 size up from stock.I am running a 135 main with the needle set exactly the same way your describing and has run flawless for 3 years at all elevations here in Alaska where we find ourselves as much as 3500 ft above sea level and as low as sea level itself.Check and read your plug if you havent already.Did you turn your air/fuel screw in untill seated then back out 2 & 1/2 turns? Start there then play with it. If need be you may need to go to a 138 main but I kinda doubt it,I think your setup is where you need to be. Just make sure your air/fuel is where it should be and see how that plays out. Hope this helps.