what jets should I use for sea level on my 400EX? I am at 3500 feet right now.

 

Can't answer the question without some more info. What pipe, airfilter mods, any engine work done, whats your jetting know??????

 

If it is still stock it is jetted at the factory for sea level, however they jet a little lean to meet environmental regs.

 

Keihin jets should work [img]i/expressions/face-icon-small-happy.gif[/img]

Ok seriously jetting is jetting and only by testing and trial and error (unless your one of those gifted mechanics who can tell how an engine is jetted just by listening to it) will you be able to have the right jetting.

As far as a ball park or basic starting point when only making a elevation change you should expect to see from 1-3 sizes change in jetting, but if the temps and any mods are also changed you need to factor those into the starting point too.

If your running a stock engine (intake and exhaust too) you will also need to consider if the engine was originally jetted for your higher elevation in the first place, and if you were not running with a little extra rich jetting all along and therfore may not need to change anything.

If you want it to be right you still need to go thru the jetting process and maybe the info in this link may help you do just that jetting