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I took the sled in trade got about 100-150 miles on it and lost the top end (well kinda..) i rebuild the top end, it sat for the summer season. I put a ilttle oil in the cylinders for initial start up today, it idles smooth, has nice throttle response but has sort of a ticking/knocking sound i know some of the sound is coming from the primary clutch but i cant tell if its just that or something in the motor.. when I rebuilt the top end i checked all the bearings in the bottom end and it seemed tight. ive put more work in to this sled than i have been able to ride it.... any help or advice would be aprecited..
 

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Remove primary clutch, run engine and recheck for noise.

I assume being a 700 it's stock bore size. Were piston to cylinder clearances checked just to be sure though?

Quick check for connecting rod bearings: Remove spark plugs. Insert screwdriver down spark plug hole, roll engine over by primary clutch, holding screwdriver straight up and down with other hand. Let the screwdriver follow the piston, but try to support its weight with your fingers. At the point the engine goes past top dead center and the piston just starts to move downwards, stop rotating the clutch and push downwards on the screwdriver. The tension of the rings to the cylinder will hold the piston in the bore until you push it. If there is excessive rod bearing or wrist pin clearance you will feel it. Compare each side and you will know if one is bad.
 

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Discussion Starter · #3 ·
I thought It was very bad to run the engine with out the clutch on it? yes i checked my clearances, when i went to order the new piston and rings i the cylinders in to the shop and measured everything because i A; didnt know what motor was actually in the sled (number plate was worn off) and B; wanted to make sure i got the right pistons. i just performed your test and i dont feel any play really at all? i did a compression test (even tho i just rebuilt it) and i came out with 146-145 almost exactly on both cylinders
 

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You won't hurt the motor running it with the clutch off. It will however be hard to pull over because the clutch acts as a flywheel and gives it the inertia to roll past the compression. It's a good sign that you can't feel any play in the rod bearings.
 

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Discussion Starter · #5 ·
ill try that next, i put a long 3/8" extension on the crank case and the jugs and put my ear to it with it running and couldnt hardly hear it> With that being said im gunna try the clutch and hopefullly thats the only issue, Thank you for the help!
 
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