I would just like to know from everyone that has a 300ex-what mods do you have, what has worked, what hasn't, different setups you have tried, and any other thing you have to say about this machine. I have a 98 300EX that I race that has a FMF megamaxII pipe, 11:1 piston, web cam, 14 tooth sprocket, dg nerf bars, holeshots front and rear, rad racing bearing carrier, works dual rate shocks in front, soon to come x-33 adjustable axle and works ultracross rear shock.

 

Mine is stock for now. I plan on doing these mods: White Bros. E-Series pipe, 14 tooth front sprocket, web cam, stiffer valve springs, modified air box lid, maybe a bigger carb, maybe a big bore kit.

 

I forgot to ask what is the Powroll Motoforce airbox lid? Is it vented and if so how waterproof? Anyone who has this lid let me know how it works for you.

 

So far on my 00 ex i've put 9 holes in box lid,put older styly supertrapp EAR exhaust w/header pipe,130 main jet,14 tooth counter sprocket,ac front bumper,and ac nerfs and renthal bars w/scott grips.
I raced a warrior w/ paddles,and an fmf pipe today in the sand and was barely edged out by about 1 to 2 lenghts in 800 ft. race.Usually this warrior beats me by atleast 4 to 5 lengths in a race.
I think if i had some paddles i could tie the warrior or maybe even win,but no more than 800 ft,b/c the warrior pulls the upper gears much better than my ex.
I'm rael happy with my engine mods they have been money well spent ,the bike pulls hard thru the entire range,i just need more power for fifth gear.A 330 bor kit should be just the thing.
When i raced the warrior the second race the ex pulled the front end off the ground thru second gear,and i almost drifted into the warrior,and had to let off for an instant to get going straight again,and he still only beat me by 1 1/2 lenghts.The 14tooth sprocket is the best investment anyone could make on a 300ex.And keep to those 22 inch tires even after you change the sprocket its a whole different quad if you do.Alot more fun.