after i install my parts- jetting question

[big jimmy t]

okay, i plan on installing an HMF sport series slip-on on my 2005 400EX that has no other performance work done to it.


in addition, i am removing the airbox lid and installing a k&n filter.


i live in phoenix, where the altitude is around 1200 feet.


the only other place i frequent with a change in altitude is buttercup, where i believe the altitude is around 25 feet.


i primarily ride in temperatures around 65-85 degrees.


can you guys give me a starting point for the jetting?
i'm sticking with the stock keihin jets.

thanks in advance, and if i am missing something or what i just asked doesn't make sense, please correct me. it's late and i've been reading about this for a while, and i think i have a basic understanding of it.

155 or 158 main, 40 or 42 pilot. I run a 158 main, 42 pilot and needle is on the 3rd slot. It runs great. I had the 155 in before but the throttle wasnt opening 100% and it needed more once i opened it to 100% so I stuck in a 158 in there and lowered the needle to the 3rd slot since i had it on the 4th before. Where i ride is about 100feet above sealevel and temperature in the winter is very similar so I think a 155 or 158 main should do the trick.

[JDMThoughts]

I just got done re-jetting my bike today, and my mods are below. I am using a 158main 45 pilot, 2.5 turns out, stock needle with the clip in the 3rd slot. The bike runs awesome, however I am at 100 feet above sea level and it's 40 degrees out. Maybe thats just the difference between my bike and yours FoxHondaRider. My thought on this if you just have a slipon with those other mods, why the high main? I have a full exhaust and even Sparks recommends 155main for their exhausts. I think 155 would be a good starting point, but would probably be too rich. The 42 pilot is a good thing to use, it will make your starting issues go away if there is any. Keep the stock needle and leave it in the middle. The only thing I can say is make one change at a time and go ride the bike and come back if the bike feels better then your heading in the right direction, if it feels worse, the go the opposite way. I know this seems very tedious but it just takes time. Let us know how you make out.