I got a 300ex with a K&N airfilter small bore and 6 or 7 half inch holes in the stock air box lid and is already jetted for the filter. Im gettin a white bros promeg silencer with the header and I just wanted to know what size jet i should get or if I even need one. If you guys got any thoughts let me know...

thanks

 

Hey I got a 98 300 ex i put the whit bros pro meg a head pipe and a k&n i tried a few diff jets but a 128 is about perfect with all 12 disks in pipe. but u will love the difference mackes it a whole new bike. but the stock 122 is good not much diff with 128 maybee more top end but slight. also have to set the clip on main needle ring clip 3 if above 5000 ft and ring 4 if below hope this helps have fun with new toy

 

ok thanks I'll try a 128