Blew up the 426!


5 replies to this topic
  • DethWshBkr

Posted June 14, 2004 - 07:11 AM

#1

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??
:awww:

  • BrandonW

Posted June 14, 2004 - 07:57 AM

#2

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

#3

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

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  • DethWshBkr

Posted June 15, 2004 - 03:29 PM

#4

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

#5

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

#6

Ain't my 4th or 5th gear!

lol.

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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