2003 WR450- yet another casualty. No start

12 replies to this topic
  • YZ426guy

Posted April 06, 2004 - 09:32 AM


This time, the bike won't start. It acted as if it fouled a plug, after riding it about 8 minutes. The battery was dead before I kicked it to life. I have put 2 new plugs in it and all it does is that "fouled plug" backfire (after about 5 kicks). I have put the battery on charge and it is now good to go. I haven't done any other troubleshooting, as of yet, as it just failed over the weekend. The bike won't start when kicked, or the magic button is pressed. I am following my normal start drill. As the WR450 Yamaha manual has limited troubleshooting hints, any advise would help. Thanks. :)

  • oldbones

Posted April 06, 2004 - 11:18 AM


Hmmm... sounds kinda like ignition. Have you tried turning it over with the plug grounded to the outside of the head (gas OFF) to look for spark?

That would be my next step.

  • Lowedog

Posted April 06, 2004 - 12:08 PM


Sounds like you may have sheared the infamous woodruff key. :) Did you have any backfires prior to this happening?


  • YZ426guy

Posted April 06, 2004 - 02:19 PM


I just came in from the garage. I removed the plug, grounded it to the head, and cranked it over. LOTS of sparks. I have had a failure of the starter clutch gear before and have had the flywheel off to replace it. I installed the new woodruff key and have loctited it.

Does this sound like a woodruff key failure to anyone? Are these symptoms anything that anyone else experienced when there's failed?

This is such crap that these failures have happened to the 2003 WR owners.

Any more suggestions?

  • Lowedog

Posted April 06, 2004 - 04:38 PM


If you are getting plenty of spark and have no fuel delivery problems then my guess would be the timing is off which is what would happen with the sheared key.
Anyone that has experienced the woodruff failure have any input?


  • Eddie Sisneros

Posted April 06, 2004 - 05:07 PM


it definately sheared the key. :)

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  • mike73

Posted April 06, 2004 - 07:32 PM


does it turn over with e-start? if so doubt it's the woodruff key. when i sheared my key, e-start would only make a whizzing sound but not turn over the engine.

  • YZ426guy

Posted April 07, 2004 - 03:41 AM


Engine DOES turn over with the e-start. Does this sound like the woodruff failure?

  • endurodog

Posted April 07, 2004 - 03:57 AM


Sounds like it to me. I have a buddy that has had his fail 2 times while I was riding with him. First time it just would spin fast. 2nd time it would turn the engine over. You need to pull the cover to find out for sure.

  • Eddie Sisneros

Posted April 07, 2004 - 04:00 AM


the key can be sheared and still turn the motor.

  • endurodog

Posted April 07, 2004 - 04:43 AM


the key can be sheared and still turn the motor

Thats what I was trying to say, that I have seen it still turn the motor and seen it not. I would bet that this is a case of a sheared key.

  • Alabama_Rider

Posted April 07, 2004 - 08:51 PM


Yet another failed Key. Yamaha will go done in history for their shoddy engineering and arrogance. They sent me a survey last week. Can you believe it? Would I buy another Yamaha? Only if Honda, Suzuki, KTM and Kawasaki were all out of business....

  • 450high

Posted April 11, 2004 - 11:42 PM


Check the key is no big deal .Once you get it home.My dealer new i was coming in to get a new key.My mates went in and told him that yamahas are [@#$%&*!],especially when we had to push it 7 ks on a stinking hot day.Its funny he had already rang yamaha and had the parts sitting there for me when i went in to chew his ear.No charge .He supplied the update 04 parts at cost also.Now thats a great dealer.His help made me change my mind about buying another brand after 6n yamahas.If it happens again tho.?


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