slip-on and jetting question

[edauth]

I have an 03 400ex and i was wondering if you necessarily have to rejet if a slip-on exhaust is installed for it to run right?

Any help is appreciated thanks

[Jessem24]

yes it is recomended

i have an hmf slip on and i run a 152 main - 42 pilot and im from 700ft- 1500 ft elevation average temp id say 75

[edauth]

I am looking at getting a DG RCM2 pipe and an aftermarket air filter. Everything else is stock, I am at about 1000 feet in iowa and usually bout 70-95 degrees in summer, what would you recommend for main, and pilot jet and needle clip. Thanks in advance for the help

[Jessem24]

try a 152 main, 42 pilot should work no matter what. if the 152 sounds backfirey, then bump to a 155. i never adjusted my needle or air mixture screw( its an 97 and its shaped like a D now so i cant adjust it, i aint gotta tool). but mine runs spot on

given your temps, close to mine and elevation almost exact, go for the 152. if you have trouble holla on here man, theres tons of helpful people on here, im only 16 and i too was asking the same ?s as you a month ago when i did my hmf slip on. i may be wrong on some but hell, mine runs great so im leaving it alone! :D

good luck, jetting is tricky :ermm: but the 152 should do!

[Jessem24]

also stay AWAY from dyno jet. there jets run smaller than the keihn hex. get them, there 5$ per jet at my local dealership.

[omeeomy]

i never did
just messed with a/f screw runs great