400ex with hmf

[wanta450]

i just got a hmf slip on for a 2005 400ex all that is done is the slip on and hmf recomended a 152 main jet so far i am up to a 158 main and i can get the outer edge of the plug black but cant get the chocolate brown on the arm it just stays like a gray metal look anyone have any recomendations on what to do o and i live in central PA

[underpowered]

the plug should be cardboard brown. how are you testing? in order to test right, you need to run the bike at higher RPM's through a field or something, and shut if off while at the high RPM. don't jsut sit there and rev it, actually take it out and ride it for a bit.

[wanta450]

yeah thats what im doin riding at high rpm then i come back my drive wide open adn kill it

[underpowered]

well as long as it isn't white i would say it will be OK. are you using a new plug each time? if not, that will cause it to not read right.

but i don;t know if it is just me or not, but my jettins is always alot richer than what others run with a similar setup. on my buddies 400 with just a pipe and filter, he is running a 165 MJ and jetting seems spot on. to me it sounds lean, but from what others are saying you are about right.

[wanta450]

bump

[zrpilot]

Gents, you are reading the plug incorrectly. In order to get an accurate plug reading you must use a special "scope" or cut the plug apart to see where the insulator meets the steel, deep in the plug.

GPRacer2500 has some great pictures in this post..reading plugs (http://www.exriders.com/vbb/showthread.php?s=&threadid=287316&highlight=reading+plug)

[Eviltanker]

Hey bud, I'm from Pa also and had to go to a 160Keihin to get the color right (with a proper plug chop). I'm also running an alum. airbox and aftermarket filter. Where is Newville?

[wanta450]

its near carlisle and we inally got it reading and running good using a 162 which is a little ways off of a 152 like hmf said but o well looks good now

[prnstr4life]

with my 12:1 piston, hotcam stage 2, alum airbox hmf slip on i am using a 155 Keihin and 42 pilot keihin wiht dnojet needle at third clip. 1.5 turns out not too much above sealevel 1k maybe??!


runs a bit rich, not sure what i need to do