new wr 426-suggestions

Howdy

just bought a basically new 2002 wr 426,just wondering what people might suggest for mods as far as exhaust,breathing and other not too huge money eater mods might be? where there any woodruf key problems on these motors? i'll appreciate any input i can get!!!!!!! :)

No woodruff issue with the 2002; The last and best 426. :)

You'll want to remove the airbox lid, and also the screen if you're up to it, and do the carb's BK mod (accelerator squirt duration reduced from stock 4~5 secs to 0.4 sec) and seal the air cut valve (stabilize the pilot(idle)circuit). All free and relatively easy. You would then need to rejet your carb. Lots of feedback available, no worries there. You should also upgrade your air filter. The Canadian muffler cannot be un-corked without major surgery, which I've done. (Check my signature at bottom). The FMF Power Bomb SX header is a great upgrade; Motovan Canada still mistakingly sells it for $228.99 instead of $328.99!(Part#327-6055). The Power Now valve is also great at improving low-end grunt and response...

Try a 'search' for info on mods. By the way, where are you and what's your elevation?

Take off the air box lid, get a YZ throttle screw, disconnect the grey wire. Uncork the muffler and replace the old cork with a GTYR end cap or get a FMF Q or Big Gun Quiet pipe. Otherwise the bike is way too loud. Try the bike with these simple mods before you go trying the BK mods and carb tricks. The motor is so good you don't really need them. Not that they aren't good. But just try it kinda stock before you get into the carb mods.

Have fun.

thanks guys

i'm in the Yukon, i'll be riding mostly 3500-4500 ft,that is once all the snow is gone!!!!!!! i do work in a sheet metal shop so the surgery is quite possible,just need a plasma and a tig???????:)

Congrats! The 02 WR426 is a great bike. I have no desire to go to a 450. Mine starts first kick with the jetting in my sig. IMO, you should do all the free mods and the YZ timing. The YZ timing is a great mod and it is free. With it, you will smoke 450's without it. 450's need to change the cam to get YZ timing, so, many do not have it. I have found that my bike really moves on non-yz timed 450s in the mid and upper rpms. Good luck, you have a great bike. Do not look back on your decision, you made a good choice. :)

Take off the air box lid, get a YZ throttle screw, disconnect the grey wire. Uncork the muffler and replace the old cork with a GTYR end cap or get a FMF Q or Big Gun Quiet pipe. Otherwise the bike is way too loud. Try the bike with these simple mods before you go trying the BK mods and carb tricks. The motor is so good you don't really need them. Not that they aren't good. But just try it kinda stock before you get into the carb mods.

Have fun.

wrjay has a Canadian WR; No need for a YZ throttle stop, there is no grey wire, and the muffler needs cutting and welding to be uncorked. Furthermore, the carb mods are virtually free and well worth it.

Search this forum for the James Now mod (home made power now). Very easy to do and worth it. I used copper plate and plastic weld epoxy. 0-1/2 throttle greatly improved.

thanks guys

i'm in the Yukon, i'll be riding mostly 3500-4500 ft,that is once all the snow is gone!!!!!!! i do work in a sheet metal shop so the surgery is quite possible,just need a plasma and a tig???????:)

Right on, wrjay! Sounds like you're good for the muffler mod. My buddy used a TIG...I don't know about plasma. I cut the end cap off at the weld; you can then pull it out with the outlet pipe. I cut my muffler body 2 1/2" shorter while I was at it and used a 6 1/2 " X 1 1/8" ID outlet with a weld near the inside tip to wedge it in it's enlarged original hole. Weld the muffler's end cap back on, then weld the pipe in the cap; It will be more angled if you shortened the muffler's body.

Good luck and let us know how far you decide to go for any jetting help.

Check out Thumperfaq.com, you will find a lot of helpful information there. :)

Good luck

I am in the process of making the AV mod on my brand new 426 that I just picked up about 3 weeks ago. I bought another boot for the carb so I can experiment with it. Once the snow clears and I get it broke in I will let you all know how the AV mod works. MELT SNOW MELLLLLLLLLLLT :)

what is the av mod?

I second that question. I recently found a posting where somebody took the time to evaluate all three (PowerNow, JamesNow, and AV Now) and posted the results. Here is the link:

http://www.thumpertalk.com/forum/showflat.php?Cat=0&Board=UBB10&Number=502868&Forum=UBB10&Words=Av+now&Match=Entire+Phrase&Searchpage=2&Limit=25&Old=allposts&Main=502260&Search=true

That is about it for the posts on this subject, and the ThumperFAQ.com site doesnt have anything either.

I'm also wondering about the details of the AV Now mod and how to go about it. Can anyone help? :)

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