ok, i have a '97 trx250 recon. i have a K&N filtercahrger in it. what i plan to do is have an open airbox, and i have jsut ordered a t-4 pro-circuit exhaust to put on it. what i need to know now is what size of jet a stock '97 trx250 recon comes with, and how many sizes up i will need to go to get the proper fuel mixture. i live at an elevation of 250 ft. ANY input would be GREATLY appreciated. thanks.

 

Stock size main was 95, and the stock pilot was 38.
It takes some trial and error to get the jets just right, there are so many varibles. Heres an article on jetting, and it explains the symptoms of lean and rich, and should help you get where you want to be.
jetting

 

thank you so much, that was a GREAt help. tahnks again.