What now after installing Yoshi slip on?

hey guys,

im pretty new to this game, so please go easy on me :D

I have bought a yz400f 99 model, and after taking some care of the little things i needed to, the time came where i had to get a new exhaust, as the old one was leaking and was dented pretty badly, and since teh front pipe was in ok condition, i just wanted to get a slip on exhaust.

I purchased a yoshimura rs3 slip on, looks nice.

Now, first of all, im not into making the most power with it or anything like that, i mostly got it due to a good deal, otherwise i would of been happy even with a stock new one.

I would like to know if i would need to make any changes to the carby mixture/jetting ect? if so, can anyone tell me what settings they have on they're carby with this exhaust(if anyone has this exhaust on?) if not, what would be the most closely recomended setting i use, since im new to this, i would like to try and get it as close as possible, so i need a starting point.

Remember, no need for outright power increase ect, i just want it to run as smooth as possible, just like stock(as i am happy with the power for now).

I havent driven it yet, but hoping to in a week or two, so any help appreciated.

cheers guys,


P.S. it has a twin air filter in stock box, if that matters.

I've got the same exhaust on my 426. I'm at sea level 80 degrees to 100 degrees, high humidity......I run 42 pilot (stock), needle in fouth clip position, 160 main jet, fuel screw 1.5 turns out.

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