emergency info request

hey all, this is really a yz426 deal, but since it involves product failure i wanted to ask the largest possible audience. i've been asked by a friend who owns a dealership to diagnose a failure for him. so, here's the question that will help me answer his:

has anyone heard of a yz4xx owner breaking the kickstart SHAFT? to be clear, this is not the kickstart lever, which was reported breaking on some early '98 models, but the actual shaft it is attached to.

thanks in advance, any info would be helpful.

if you don't mind, please copy my personal email at wpattison@ignition.com with any answers by close of business monday.


will pattison

racer, engineer


damm you must have one hell of a kick i've never herd of this before

The shaft itself broke? Not the ratchet mechanism, stop, case, splines, gear, or idler gear? Maybe the ratchet jammed and the motor broke the thing via the idler gear.

More than one person here has had the stop somehow come out, it is a strip of steel secured by two bolts to the cases.

Here’s one post on the subject.

Here’s anotherone.

This happened to me also (but it was on a high compression extremely modified XR400)...the day my Dad brought my new bike home he went to start it up (and of course my Dad kicked the thing like a 2 stroke w/o finding top dead center) well since my dad is a BIG fella (6ft 3inches 265 lbs) the countershaft snapped like a twig (but remember the XR countershaft wasnt made for high compression) well after 2 wks of waiting (remember I havent even rode the brand new bike yet :D ) we split the cases and put it back together and now it runs great (since he knows how to start it)

I belive the YZ is made for high compression since it is :) If i were you I would take the right cover off (ive never done this on a YZ so I cant give u the particulars) and check to see if you busted the sprocket on the kickstarter mechanism or maybe it popped off out of the groove!

What kind of noise does it make when you depress the kick starter? Does it even move?

Hope this helps!



I get my kicks on a 2001' YZ426!

Friendswood, TX

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