Big problem on my yz450 '07 broken crankase

6 replies to this topic
  • publio71

Posted April 29, 2007 - 03:18 AM


Today i was racing on my region championship where i live, and at one time the gear dosen't go in, and the bike stop. I look on my bike and i see the crankcase broken.My is a 07 yz450f, the same problem happen to some one????? Thanks if some one can help about this.

  • dooweb2

Posted April 29, 2007 - 03:31 AM


did the bike lock up and stall while riding? and kick starter locked up ? its possible . one of your gears is coming apart.. yes you have to split the cases to fix.. but it could also be something else

  • publio71

Posted April 29, 2007 - 06:47 AM


The bike start whit no problem, but have a hole in the back side of the crankcase and the gear dosent work.

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  • grayracer513

Posted April 29, 2007 - 08:17 AM


You don't have any options. You need to take it apart and repair as necessary.

  • publio71

Posted April 29, 2007 - 11:34 AM


What i am asking if some one have the same problem on gear, i know i have to repair, i just ask if some one happen the same.

  • grayracer513

Posted April 29, 2007 - 11:52 AM


There have been a small number of people who have had problems with a failure in the starter gear train. These gears turn full time, and if something goes through them, or they break, they can damage the cases. However, if I understand you correctly, the engine starts and runs OK, but will not move. If the problem was in the starter gears, this would not be true.

  • BergArabia

Posted April 29, 2007 - 12:42 PM


Sorry to hear about your gearbox ...
Sounds like a new case for you..

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