Jetting question???

[thinkfaster]

So a buddy of mine wants to trade me a full white brothers exhaust for my stock exhaust. I have the stock tip with the spark arrestor as well as another tip with the spark arrestor removed. He keeps getting the cops called on him so he wants to be able to quiet it down when riding around the house. Now to my question, will i HAVE to re-jet my carb with the full white brothers exhaust? its a bone stock 02 400ex...if so, any guesses as to what i should start with size wise? ive read multiple jetting threads but some stuff is still unclear to me so i decided to go ahead with this post. any help is appreciated!

[JOHNDOE83]

What part are you not understanding? just curious...

try www.jetsrus.com in the FAQs section.

[thinkfaster]

I was having trouble understanding that you just have to make an educated guess to get jet size you need...i know finding a chart or something that tells you "if you have a stock filter and a full white bros exhaust and you are between xxx, and xxxx ft. above sea level, use a xxx main and xx pilot " is out of the question. But being that an exhaust is a popular first mod, i hoped someone could give me a good idea of where i needed to start. By the way, im right about 850 ft. above sea level.

[thinkfaster]

Found the answer to my question pretty much...i didnt find that site in my searching somehow...thanks for the link JOHNDOE83!

Few more questions:

What size are the stock jets in my 400?
My carb is a Keihin right?
Is the main jet a "99101-357 HEX"?
What kind or # is the pilot jet?

[JOHNDOE83]

148 main and I think a 38 pilot