i have a 2000 300ex the only mods that it has is a slip on white brothers pipe and a K&N filter with a open air box.it runs good.but 1-3 feels like it has a govenor or something like that.it seems like 1st gear -3 gear wind out to quick.then once you shift out of 3rd gear to 4 & 5th it's fine.i thought that it might be the rev limiter or the cdi box.can i buy a aftermarket cdi box with the mods that i have..???

 

yeah dude, just with a stock motor u should keep it under +1000 or so, and one thing u can do to get some extra flow is cut out the fins in the air box, and grind out the little lip in the header, and make sure that the jetting is right on.... i've gained 2hp just with jetting. PM me or something if you want some more 300ex tips, i got tons