Author Topic: oil leak on new bike left side  (Read 355 times)


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Re: oil leak on new bike left side
« on: January 25, 2017, 11:22:47 am »
My guess on the source of the oil is a pinched o-ring or poor seal for the sensor to shift drum interface.  As for noise there are a couple of areas that I have found make them sound like farm equipment.  My 690 has 16,000 miles on it.  First is the rocker arms. They were making lots of noise I first thought were wide valve clearances.  Although that really didn't make sense to me.  I checked and found the problem. I've replace both intake and exhaust because the intake rocker bearing was so worn out. I could not even believe it was still running as strong as it did.  The second sourc is the crankshaft main bearing.  I'm replacing mine now.  The play wasn't sever but a definite rattle when I took the cylinder off and gave the small end of the rod a wiggle side to side and twisting side to side.  The clearance between the big end and the crank was in spec but very loose feeling.  Once chucked up in the lathe I could really make it noisy by grabbing the small end to turn the crank.  Anyway I bought a new crank and it sure is tighter and smoother.  The engine isn't back together yet.  I've heard that if a KTM engine isn't noisy then it must be broken though.  I'm hoping the engine rebuild was not a waste of time and money.  There is also another area of potential noise some 690's have exhibited and that is the balance shaft bearing surface.  I didn't have that issue.