Blew up the 426!

5 replies to this topic
  • DethWshBkr

Posted June 14, 2004 - 07:11 AM


Dad blew his motor yesterday on his '00 426. He said it make a terrible sound at low RPMs as he was accelerating coming out of a turn for a jump, so he stopped and shut the motor off. Now it will not kick over.

It's a 2000 model, NEVER been apart... :thumbsup:
I wished he'd had rebuilt it last year, but he didn't want to.
Oh well!

What are some possible things that may have gone wrong?
I'm thinking valvetrain somewhere. I doubt the cam cahin broke (like mine did), cause it was still running, but making a bad sound.
I guess it's POSSIBLE he jumped a tooth or something, which could have jammed a valve into the piston.

There is no visible external damage - so hopefully it won't be too bad of a rebuild. But what do you guys think??

  • BrandonW

Posted June 14, 2004 - 07:57 AM


Hope for something simple!

Maybe a piece of the carb slide plate broke off, and is wedged in a valve.

Sounds like crap! But, rarely does any damage. I've done it 3 times!

Good luck, whatever it is....

  • Satch0922

Posted June 14, 2004 - 02:40 PM


2000 models had a problem with the crank keyway. Do a search here and you may find your problem.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • DethWshBkr

Posted June 15, 2004 - 03:29 PM


Dad's got the clutch off, and now the bike turns over. SOunds like something in the tranny may have gone. Seems like you guys have issues with 4th and 5th gears??

  • Satch0922

Posted June 16, 2004 - 02:44 PM


Seems like you guys have issues with 4th and 5th gears??

Actually it sounds like YOU have 4th 5th gear problems!

Seriously there have been issues with 3-4 th gear. Do a search here on that also.

  • DethWshBkr

Posted June 16, 2004 - 05:09 PM


Ain't my 4th or 5th gear!


Dad pulled his clutch basket, and now the engine turns over. You cannot always spin the back wheel, sometimes it locks. Sounds like definite drive train.

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