sticking decompression pin

I put a new piston in my '08, started fine but the decompression pin stayed engaged. It made a lout tick obviously, until I rapped it out on the track, took a 1/4 lap riding hard to stop ticking. Now I can barely kick it over, I can but I'm afraid of tearing my ACL. I took the valve cover off and noticed the decompression weight had not returned to where it should have. So I grabbed it and wiggled it a little and the weight went to where it should. It's now easy to kick over but it does the whole process again. I took the cam sprocket off and tried manipulating the decompression shaft by hand and noticed it sticks lightly. I got the manual out and the pin is installed properly as was the shaft and weight assembly. I'm planning on checking the decompression pin for burs, but until I try that I was wondering if any one has experienced this and if there is a simple remedy. Thanks.

Got some dirt in it or the return spring has come out/broken by the sounds of it. Only other thing, as you say, could be burrs on the pin making it stick.

There might be a bur on the inside of the cam, seen that with some aftermarket cams not on any stock ones.

:worthy: When I took the engine apart I was talking on the phone instead of paying attention, and I stripped the allen screw that holds the cam gear to the cam shaft. To get it out I pounded a Torx socket into the allen screw and then used a mechanical impact driver on it, I was surprised that one of the ears didn't snap off the cam shaft. On closer inspection the ears ( where the two 6mm allen screws go) are pressed on to the cam shaft and in the process of hammering out the stripped fastener I pushed the ear assembly about 50 thousandths of an inch down the cam shaft. So when I tightened the cam sprocket to the cam shaft it caused the decompression weight to bind on the resulting lip. I fixed it with a bearing puller and a 3 pound flying press. It now functions properly. :D

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