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

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

Related Content


The "going back to the other darkside" adventure... by Monk

Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  94 replies
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

YZ450F 03 Sparks driving me crazy by SirAttard

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.