YZF400 broke in two...

6 replies to this topic
  • James980

Posted January 15, 2002 - 02:01 PM


...well, the cases did -- when this big fat guy kickstarted it. If anyone has any leads on a used set of cases and a right side engine cover (or advice on attempts at repair) it would be *much* appreciated if they would pass the info to Mike at mkeefe@midwestmotocross.com. I'll also tell Mike to check here.



  • YZ400Court

Posted January 15, 2002 - 04:48 PM


I'm a big fat guy. Maybe I should not kick my bike? What happened?

  • Kirtwell

Posted January 16, 2002 - 11:02 AM


I'm a little on the fat side too..should i know something before I bust my cases too

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  • yz454

Posted January 16, 2002 - 06:59 PM


I know TRC can help you with your cases.contact me .

  • James980

Posted January 17, 2002 - 05:15 AM


Originally posted by YZ400Court:
I'm a big fat guy. Maybe I should not kick my bike? What happened?

He started it, rode about 60 feet, came back to the truck, stalled the bike and started it again. This time, the kickstarter stayed down, he rode it about 10 feet, stalled it again and then noticed the broken cases. My guess is either:

A) the kickstarter return spring broke and a chunk wedged between the clutch basket gear and kickstarter gear, putting lateral pressure on the kickstarter shaft and forcing the case to crack; or

:) it just freakishly broke after the first quick ride; thus, the kickstarter shaft was out of place; thus, the return spring was not engaging.

Him being fat actually probably didn't have much to do with it, although the ugly factor may have come into play.


  • Victor_Delgadillo

Posted January 17, 2002 - 08:46 AM


I think that you'll have problems with the kickstart assembly, may be when the kickstart stay down and the bike was running the hole gears made a mess inside... probablly is the same that happend to me, but i do not start the bike... and the repair cost me about 350.

  • Thumpy79

Posted January 17, 2002 - 01:27 PM


The same thing happened to my brother-in-law's KTM. When the kick start is down and the bike is in gear and moving, the gearing goes haywire and crack goes the case.

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