best mods for the 02 426?

just picked up a 02 426 that dual sport converted, but i want more power...

all it has is a jd jet kit and bk mod...

would both power nows, a quickshot or p-38 cover, and a fmf powerbomb header fill my need for boost?

also, whats the best sounding race exhaust for the 426?

was thinking the stocker sounds pretty good...and probally only need the powerbomb header mated to the stock can...

but maybe a good shorty ti can for the powerbomb header would do the trick...

anyone???

i am only 15 and i have the exact same bike as you. mine has a complete dubach racing pipe (that includes the head pipe) UNI air filter, i think it has a high compression piston, iron man sprocket, D.I.D. gold o ring chain, maxxis tire's, azonic bars, oversized tripple clamps, and custom front suspension. the best part about this bike is that it will do a wheelie in all five gears WITHOUT using any clutch. one time i did a wheelie past my dad doing about 65 mph and he got all mad at me. but my dad has a '01 yz426f. and he has an hot cam that removes the decompression release lever, a desert tank, and dunlop tires but he just trail rides.

The Power Now's will do little or nothing for your peak power. They're not supposed to. The intent is to improve throttle response by improving the airflow through the carb at part throttle only.

The best exhaust for the bike is a complete system engineered for it, not some Frankensteined "Shorty Can" deal. A complete FMF system is one of the good ones. Noise does not translate into power in any very direct way.

IMO, the best single modification you can make to a 426 is the YZ450 exhaust cam. You'll end up with auto decompression, ditch the starting drill, make the bike easier to bump or restart on the fly, and get a power boost in the process.

I have a Wiseco 13.5:1 piston. It greatly improves the low end grunt and mid range hit.

Must do 426 mods:

450 cam, Thunder Alley exhaust, GB mod. Anything any more than that is all rider preference. The 450 cam is hands down the best cash you'll spend on a 426... enjoy the new ride!

IMO, the best single modification you can make to a 426 is the YZ450 exhaust cam. You'll end up with auto decompression, ditch the starting drill, make the bike easier to bump or restart on the fly, and get a power boost in the process.

This is the first I've heard of the 450cam mod making a power boost, I thought all it did was negate the starting drill which I don't mind. I might have to do it now. :crazy:

grayracer has a very good point, the fmf system is the wat to go for exhaust and the 450 cam mod is hands down the BEST all around mod that can be done. above and beyond the fact that given proper maintenance these bikes are virtually bullet proof and almost fool proof.

I had the same year. I went with the power now....and a White Bros e-series. Worked really nice.

i have a 00 yz 426 with the bk carb mod. i have 2 exhausts, an fmf powerbomb with q silencer, and a full procircuit t-4 system. the t-4 was a huge power difference but is very loud. the fmf system is great too..better torq but not as much overall power which i am guessing has to do with the fact that its a quiet trail silencer versus the full t-4 race system.

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