Auto Decompress sticking on '07?

2 replies to this topic
  • DusTRhodes

Posted August 12, 2010 - 12:27 PM


A couple of times this past year while sitting on the line going through my pre dead engine start routine my engine pretty much locked up after a firm kick from the top of the stroke. In one case the kick start broke loose and racheted as I tried to push through the stroke. Both times that it locked up, all was fine after a minute or so of waiting. At the time I figured that the auto decompress wasn't doing it's thing for some reason.

Now ... I have the top end apart. The decompress mechanism operates smooth as silk but the paw feels sticky when leaving the contact surface on the cam gear and starting to move inwards. It seems like it has a tendancy to stay in the outward position but hasn't stuck while I was playing with it.

Any ideas how to fix this sticking tendancy?

This is on an '07 with a Rekluse.


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  • grayracer513

Posted August 12, 2010 - 01:08 PM


Read this first:


Now, it could be simply that you are kicking the engine over so fast that you are causing the flyweight to swing out, retracting the AD pin, and thereby making the AD system inactive. The flyweight swings out at around 700 RPM, so it's actually possible to do this, and then have the crank park itself at the beginning of the full compression stroke. In this case, the solution is just to kick a little slower.

If it's actually sticky, it may be kind of tough to correct, since the mechanism is pressed together (the flyweight pivot pin holds everything together). Maybe pulling the cam and cleaning things thoroughly will do it.

  • DusTRhodes

Posted August 13, 2010 - 10:50 PM


Thanks Gray!

Had more time to work on it tonight. A little bit of solvent where the arm rests on the gear inner surface removed the sticking tendency.

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