What about a flywheel?

Ole blue is YZ timed and I love it! The rip is awesome. But in much of the terrain I ride the initial hit is too much, but the WR timeing is too mellow for me. What is the Factory WR flywheel weight? Has anybody experimented with a heavier weight, and what did you like/dislike about it?

Thanks Guy's


I'd like to know too. I've been considering getting a 12 or 14oz flywheel weight to help with traction in sandy, loose, nasty hill climbs. If anyone has some experience with these things I'd like to know too. Also, how was the install? Major pain, fairly easy?

What needle are you using???

Steve and SoCal,

I use a 12 oz flywheel on my 99 and barely noticed a difference in hit or power. However I noticed I can run a taller gear through the woods (all that I ride) and I can drag the rear brake a little to scrub off a little speed with no fear of stalling it. It also seems to grab traction a little better, probably due to running in taller gear. I bought mine from stroker and it is a bolt on. I am very happy with it.


are the WR and YZ flywheels interchangeable?

Yep The yz and wr flywheels are interchangable. I have a wr flywheel and stator on my 99 yz400. As said above, I can't notice any differance in the power or hit. But it does work better offroad. I stall alot less.

Do you have any idea what weight the stock fly wheel weight is? It's probably in my manual but my wife & daughter thought they'd do me a favor and clean my work bench. Now I can't find half of my shyte.

I have no idea what the weight is.

Sorry guy's, I believe the stock flywheel might be 12oz. But I'm far from positive. I'm thinking that heavier than stock by 2oz. or so would give the mighty beast a bit more hook-up in the loose stuff at the very bottom end of power band. I'm hopeing that someone that has experimented will step in and speak up....SoCal

Can you put only WR stator in a YZ, or you must also use the WR flywheel? A friend of mine with YZ wants to put lights. He will need regulator too, doesn't he?

Sorry guys, as you all can see that I'm a newbie. I'm wondering what is flywheel?? Where is it located?

Sorry for the ignorance...

This is the magnet under your left crankcase cover that is rotating around the stator to produce electricity AFAIK.

Hey Sabin,

Have your friend call Electrex. They can hook him up with a wr flywheel and stator modified to work with the YZ ignition. They charge $300.

link to Electrex site

They also have the voltage regulator that he will need. It is like $15 I think.

You can buy a stock wr flywheel and Stator from yamaha for like $250ish but you will have to modify it to make it work on the yz.

link to how to modify stator.

Hope this helps.

Sorry guys, as you all can see that I'm a newbie. I'm wondering what is flywheel?? Where is it located?

Sorry for the ignorance...

Death Knight, You're not ignorant at all. Hang out with us and learn as you go......

SoCal, The weight will defiantly help smoothen out the power delivery of the bike, it gives it a tractor feel. I have the WR timing and love it, I can't even hang on to the bike in stock form and plenty enough for little ole me. If you feel that WR timing would slow you down then Do NOT get a flywheel weight because it will mellow your bike out more than going back to WR timing. I truly believe that the biggest weakness of the WR is that it's a handful in the tight stuff, not a woods bike at all. My suggestion is to go back to WR timing to get rid of that initial "hit" that's so abrupt.

Peace my brother..


Socal has weight but its just not on the flywheel. javascript:void(0)


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