07 450 - can't kick with spark plug in, can with out


8 replies to this topic
  • fldrifter

Posted December 28, 2013 - 04:34 PM

#1

This seems to be a different issue than my last valve seal problem. The bike ran fine and kicked over fine, this has come up now after that was solved.

The bike is almost impossible to kick over with the spark plug in. I took the plug out and I can kick the bike over fine. No issues, feels like it should. Put the plug back in and I can get half a kick before it's a brick wall. Bike has spark as well, tested it.

I thought it is my auto decompression, so I put the bike in third gear and was able to roll it a couple feet back and forth and can hear the cylinder moving. But still a brick wall when trying to kick.

Second problem, possibly what my issue above is. My clutch lever does not seem to put the bike in neutral. I have adjusted the lever and even used a bar to pull the mechanism on the transmission back but the bike won't come out of gear. I can change gears for the most part without it. What I mean is shifting to first gear, it will sometimes shift, other times it stays in neutral. If it shifts properly the bike will go through all gears without issue. If it doesn't shift then it stays in neutral no matter what.

I have taken the clutch / clutch basket out. Everything looked fine and the bike would shift gears seemingly fine. The basket is fine as it has no groove wear from the plates.

I'm at a loss at this point. What do I need to check or look at?

  • Arizo

Posted December 28, 2013 - 05:50 PM

#2

I can be wrong but the problem about not being able to kick it over, maybe your exhaust valves don't open up?

  • grayracer513

Posted December 28, 2013 - 07:51 PM

#3

Cam timing.  The exhaust cam has slipped, probably because the chain has kinks in it.



  • fldrifter

Posted December 28, 2013 - 07:55 PM

#4

Tomorrow I will take the valve cover off and take a look. If the chain kinks should I order a new one? Preferably with a master link so I don't have to take everything a part?

Also, when setting TDC, my crank has 3 mark lines? The manual says nothing about 3 marks, just 1. I used the middle one, was this correct?

Edited by fldrifter, December 28, 2013 - 07:59 PM.


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  • grayracer513

Posted December 28, 2013 - 08:01 PM

#5

The chains don't come with master links.  If the cam timing is found to be incorrect, the chain needs to be replaced.

 

http://www.thumperta...f/#entry2520291



  • fldrifter

Posted December 28, 2013 - 09:09 PM

#6

Thanks for the link, I will need to order a flywheel puller with the chain if I find that to be my problem.

  • fldrifter

Posted December 29, 2013 - 10:25 AM

#7

I don't know how you have answers for everything, but you were correct. No surprise there.

http://i.imgur.com/jibr772l.jpg

Exhaust cam has slipped 1/3 the way around. Makes sense why the bike ran the first two times I fired it up after the rebuild. As it hadn't slipped yet.

  • grayracer513

Posted December 29, 2013 - 01:07 PM

#8

And the chain is bad, by the looks of it.  Note the circled links.  All the pins on the top run should be on the same straight line.

 

What happened is that the engine "bounced back" off compression once as it was shut down.  The reversal of tension pulled the kinks out on the back side, leaving slack in the front, and slid the chain over the exhaust cam.

Attached Thumbnails

  • jibr772l.jpg


  • fldrifter

Posted December 29, 2013 - 01:26 PM

#9

Ah I see the kink in the picture.

I've ordered a flywheel puller and new chain so happy new year to the bike work. Lol





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