OK...I have a question(s):
1) what exactly is this compensator I keep reading about?
2) and, what exactly does it compensate for?
3) finally, why does it seem to be such a problematic component in 110's.
Please...don't tell me that as a new SERK owner I'll have wait for it to crap-out to understand!
1. It's basically the primary drive sprocket on the left end of the engine shaft. It has three ramps and springs in it, to attempt to provide some cushioning between the engine and the rest of the drive train when you transition between power on and power off.
2. Its function is to help compensate for the stresses that are delivered to the crank shaft via the primary chain from the rest of the drive train, to provide a smoother transition between power on and power off. Harley cranks are notorious for having high runout ever since they went with the pressed-together crank on the Twin Cam engines. The compensating sprocket is an attempt to keep these cranks living longer, by trying to take up some of the slop in the rest of the drive train, so the force doesn't bang on the crank so hard when you accelerate or decelerate.
3. The comp has always been a troublesome component. The MoCo is on their 4th or 5th design change on this thing, and they continue to fail prematurely. It got worse in '07 when they implemented the new CruiseDrive drivetrain for the 96" engines, and the 110" engines on the CVOs. The newest comp version has a plastic ramp that glues onto the inside of the primary cover, to attempt to provide better oiling of the comp. The '14-up outer primary covers have the ramp already molded into them from the factory.
I've been thinking about going to the Evolution Industries solid sprocket to get rid of the comp altogether. But then, I'd probably have to get my crank welded/plugged/balanced, with the Timken bearing, so IT wouldn't fail prematurely. I will probably have to do that anyway at some point.
Unless you ride very lightly, you will have comp issues at some point. I ride hard, and my comp is going at 19,000 miles. Many have failed with many less miles. Engine kickback on starting, a backfire on starting, rattling noise in the front of the primary, a loud THUNK when turning the engine off, and general jerkiness in the drive train are all symptoms of comp failure. My bike has all of these symptoms.
Hope this helps.
Ken
Author
Topic: 103 verus 110 (Read 8989 times)