is this engine reasonably fixable? kickstart issues

4 replies to this topic
  • ironmonkey

Posted May 25, 2013 - 11:31 PM


Hi, I bought a yz450f engine off ebay with the knowledge that the kickstart housing was completely blown off, however the blown off part is not structural. Seller claimed kickstart works but it is jammed. Seems like one of the two kickstart bolts came loose, the kickstarter then severed it off, with half the bolt dangling inside and causing mayhem, resulting in the blown case and the jammed kickstart.

Here are the images below:


Do I really need to replace the severed bolt? I have no idea how a kickstart works. I havent assembled the engine back to try the kickstarter again, and wont be able to until next weekend. I'm planning to use this engine for a go kart, so there wont be frequent kickstarting.

Edited by ironmonkey, May 26, 2013 - 06:17 PM.

  • Geoffit

Posted May 26, 2013 - 05:38 AM


For the ks to work all of that stuff needs to be there. The broken bolt can be removed but it looks like the shaft hole in the case is mangled as well. A fair amount of labor is needed . You will need to split the case for sure

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  • ironmonkey

Posted May 26, 2013 - 05:59 AM


What does the bolt do? The kickstart should still crank the engine over, which for my purposes is all I need.

The shaft hole is okay, I think the mangledness you are talking about is just the washer sitting on top of it (sorry for the poor quality pic). Unless you are referring to something else?

Edited by ironmonkey, May 26, 2013 - 05:59 AM.

  • grayracer513

Posted May 26, 2013 - 02:57 PM


The bolt anchors the plate that cams the ratchet out of engagement so it doesn't run against the gear while the engine runs. Looks like a lot of welding and machine work to me.

  • ironmonkey

Posted May 26, 2013 - 06:16 PM


where is the required machine work?

What i know at the moment, is that if I want to plow ahead I will need to source the bolt and plate and chemiweld the blown casing back (as its not structural).

Edited by ironmonkey, May 26, 2013 - 06:19 PM.

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