I have a 04 300 EX and i just got a full white bros e-series exhaust and a uni filter, im getting a jet kit in a couple of days and i have no idea what i should be looking for. People talk about different sizes but i heard different since i have a full exhaust. If anyone could help me out it would be great. And i need advice in what im lookin for if im running too lean or the opposite... thanx

 

Since you are getting a kit it will come with an assortment of jets and a base of where to start. In general you need to go richer. You are going to want to open up the airbox somehow too, preferably with a prefilter of some sort.

 

do you think it is good to cusrtomize the airbox?? like holes with screens or what??

 

I WENT WITH A 133 MAIN JET... WITH A DUNCAN DOUBLE BARREL FULL SYSTEM......... AND KEPT IT WITH THE PRO CURCUIT SYSTEM

 

Yes, like the small UNI vents, a K&N powerlid, or just rig up something yourself by cutting up an old foam filter with some holes in the lid. I took some plastic screen to hold the foam to the underside of the lid. Not as pretty as a powerlid but just as functional.

 

When I put the IDS2 full system on my son's 300ex, and put 4 1" holes in the lid, I went 2 sizes up on the main, and one up on the pilot. Hondas seem to come lean from the factory to meet emissions or such, and his 300ex was always a little cold blooded, going up on the pilot really helped with starting and low end throttle response. You may want to look into an aftermarket cdi, the stock rev limit is so low, the extra rpms you will be able to pull with the new exhaust might have you shifting sooner to get the most out of it. If you regear or change tires to smaller size, you will definately need a higher rpm limit to be able to get the full use out of the extra power.

 

hey thanx for the advice but i dont konw exactly how to regear if you can give me some tips, when i bought my bike i didnt even get my manuel with it so i dont even know the stock setting for the jets and the gears if you could give them to me that would help alot.. thanx