YZ ignition on WR?

12 replies to this topic
  • supermoto400

Posted December 30, 2002 - 04:50 PM


In an effort to make my WR feel a little more like a YZ, I have done the YZ timing mod. and this has helped. I would still like it to spin up a little faster and was wondering if anyone has tried installing a YZ flywheel on a WR? I've been told that I would need the CDI, flywheel, and stator from a YZ to make this work. Also, what additional mods to the carb., if any, would need to be performed?
Thanks for any input...

  • MN_Kevin

Posted December 30, 2002 - 05:39 PM


I have a hard time thinking you will need a YZF stator and flywheel to go w/ a YZ CDI...

I am no electrician / electronics tech, but it don't sound right to me.

Call me an imbecile! :)


  • yamaha.dude

Posted December 30, 2002 - 06:44 PM


you are on the right track, looking for the lighter flywheel is the way to get it to spin up faster, but I don't have direct experience of if you need the other bits and pieces...

Try searching in both the WR4xx and YZ4xx forums using 'flywheel weight'... the advice you may get from the search may be the opposite of what you are looking for (i.e. info about putting a heavier weight on a YZ), but you will figure it out from reading...



  • dirtdynamics

Posted December 30, 2002 - 06:54 PM


Let me know how it turns out,
i ride a WR so i may consider converting to YZ
just like you.


  • endurodog

Posted December 30, 2002 - 08:58 PM


I may be way off on this but is the CDI the same in both bikes?? A quick call to a Yamaha parts counter should answer that one.

  • PumpkinHumper

Posted December 31, 2002 - 05:46 AM


I bought a wr stator and flywheel for my yz400. Electrex said that the stator had to be modified to work with the yz cdi.

So I would imagine if you wanted to use a yz flywheel ( I have a spare) you would have to use the yz stator ( I have a spare one of those also).

If electrex can modify a wr stator to work with a yz cdi maybe they can modify a yz stator to work with the wr cdi. That is if any modification is necessary. Call Electrex. Im bettin that they would know the answer to your question.

Another thought. Maybe you can have your wr flywheel lightened by a machine shop. I have heard of this being done on other bikes like tt-r 90's.

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  • GPS Dual Sport

Posted December 31, 2002 - 06:42 AM


I know when the bike was first released back in `98 the WR and the YZ had the same part number for the CDI box.

  • SFO

Posted December 31, 2002 - 08:36 AM


I am running a 98yz400 motor in my '01wr426 right now.
I have tried both ignitions on the 400 with the wr cdi. They both work.
You will need a stator to match the rotor ie wr/wr, yz/yz.
Both plug into the wr cdi and work.

  • supermoto400

Posted December 31, 2002 - 12:23 PM


Thanks for all the input on this guys... once I find a YZ flywheel, rotor, and stator, I'll be sure to post the results and let you know how it turned out.

  • Andrew_in_OZ

Posted January 01, 2003 - 03:20 AM


there is another option. DUAL curve CDI's they offer both yz and wr ignition curves which can be changed on the fly (while in motion) takes 10 mins to install no need to change rotor, stator or flywheel and have the best of both worlds, there are a few manufacturers vortex, wulf etc. im using an original vortex on my bike at the moment the new model has a 10 map selector switch and power/traction handlebar switch check em out at www.vortex-performance.com.au

  • SFO

Posted January 01, 2003 - 03:15 PM


My results with the vortex were less than sterling although it wasn't used on a stock motor.

  • Andrew_in_OZ

Posted January 02, 2003 - 12:32 PM


have you or did you attempt to adjust the curves to suit your modifications.eg wr curve works best with wr mods, yz with yz mods, another curve for another mod.would you change heads pistons inlet exhaust etc on a high performance car engine without re-setting your distributor advance to suit the mods?

  • BigDesto

Posted January 02, 2003 - 12:50 PM


I thought the grey wire when unplugged was to map the ignition like a yz? Anybody?


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