wondering about HMF

[rides_red25]

i am a new member yesterday. i am currently running a full system white bros. e-series i purchased in June on my 400EX. my brother put a slip-on HMF on last week and i can't even come close to his now. before i could beat him.
well my real question is that is slip-on HMF better that a full system? i read on here that most of you put slip-ons on rather than full system

2001 400EX
full system Wh. bros. e-series
wh. bros. rev box
k&n filter
coming soon dyno jet kit stage 2

[hondarider2006]

your not already jetted:eek2:


Also is he running a filter and jetted with his bike, or just the slip-on?

[cals400ex]

yep, jetting makes a difference. also, make sure you don't have more than 1/4 inch of slack in the throttle cable. if you do, adjust it so you dont.