08 yz450f kickstarter problems

12 replies to this topic
  • akoett

Posted March 15, 2010 - 04:50 PM


:lol: I was at the dunes this weekend and had been riding for about 30 minutes. got to the top of a dune and my bike died. I tried kicking and kicking, noticed that the kickstarter was extremely hard to kick like that is almost a catch. After i had gotten it started my bike sounded totally different (exhaust sound) I need some ideas of what this could be ? :banana:

  • tek_01

Posted March 15, 2010 - 05:26 PM


jumped time?

  • akoett

Posted March 16, 2010 - 09:18 PM


as in jumped time you mean? Would timing make my kick starter do that tho? and I was also wondering if it could be that my valves arent adjusted right?

  • ragge86

Posted March 16, 2010 - 09:48 PM


he means the camchain jumped 1 on more tooth on either camshaft. check if the cams&crank line up with the marks, you can find out how in the manual.

  • akoett

Posted March 18, 2010 - 08:58 AM


hey thanks guys I will check this as soon as i get some time. I will let you know how it turns out! I also wondered i seen a bunch of other guys having this same problem jumping time, and they say that it messed up there whole top end ? whats that all about?

  • tek_01

Posted March 18, 2010 - 01:07 PM


timing is when everything basically rotates "in time", so if your piston is moving up when it should be going down than it may hit your valves etc and totally destroy your motor. If it only jumped one tooth than you should be ok in regards to damage but should find out why it did it (stretched/kinked cam chain or faulty tensioner maybe)

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  • akoett

Posted March 18, 2010 - 07:06 PM


I checked my tensioner and it is fine! the chain looks ok! but what I am wondering how this made my kickstarter so damn hard to kick

  • grayracer513

Posted March 18, 2010 - 07:38 PM


If the exhaust cam advances by one tooth, the timing of the auto decompression system is thrown off with it, and there will be so much compression that you basically can't kick through it.

  • akoett

Posted March 18, 2010 - 10:07 PM


You guys have been a lot of help. I know i might sound a little off in the head with some of these questions but this is my 1st 4stroke ive torn into so. Thanks again.

  • tek_01

Posted March 19, 2010 - 01:50 AM


So what was the verdict, how does the timing look? all the marks line up?

Do you have a manual?

  • akoett

Posted March 22, 2010 - 09:45 PM


Hey I found out I did get a little sand in the motor, and the timing jumped one tooth. So I am going to put a top end kit in it and a new timing chain. I really do appreciate all of your help guys.

  • akoett

Posted March 23, 2010 - 06:58 PM


Can I hone my cylinder there is a tiny, i mean tiny line in it

  • tek_01

Posted March 23, 2010 - 07:08 PM


You can use a ball hone to lightly hone your cylinder however if the line is deep enough to catch your fingernail when scraping it through the cylinder, than i'd say its too deep.

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