103cu Problem
103cu Problem
Need some feedback. I have 2010 SG with 103cu,255cams,SE Pro Tuner,V&H Power Duals and Hi Output Slipons. Bike has ran great since I did all upgrades at 5,000miles. Now at 14,000 When I crank it over it makes a violent noise and almost sounds like its kicking back and does a hard back compression thu the throttle body. I am a heavy equip mech for about 18yrs so I am handy with the wrenches,but I am not a VTwin Mech. Wrenched on them very little. So any input is greatly appriciated. Ps I do not have the auto or manuel de-compression. Some have said I need them. Not apposed to doin them. Just curious if i needed them why I has not did it till 6,000mi later.
Intermediate
Joined: Jul 2008
Posts: 31
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i would lean toward a compensator issue.......... I have a friend who's bike started making horrible sounds when cranking, and recently while going a steady speed, it souded like a thrashing machine eating boulders, then cleared up shortly afterward. He rode on for a couple months until the "latest" SE compensator came in yesterday and in the shop now getting replaced under warranty.
been wathing compensator posts for awhile, and bad cranking sounds can be a symptom.
been wathing compensator posts for awhile, and bad cranking sounds can be a symptom.
Outstanding HDF Member
Joined: Jul 2007
Posts: 3,341
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From: Woodinville, WA
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Cruiser
Joined: Jul 2007
Posts: 219
Likes: 0
From: Central Illinois
Save yourself the trouble if it was the compensator it would be an issue while running...not just cranking. I change about a clutch a week, its the weak link to these increased displacement engines.
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From: Phoenix '53, '88, '09 Big Twins
the starter can easily be activated from inside the primary...turning the chain and plucking off fingers.
what ever you find I think you will want to add compression releases.
the H-D does not have much in the way of flywheel ( so they will rev faster)- this means less stored energy when trying to rotate against compression.
remember that the motor ALWAYS stops on a compression stroke- and to push over TDC is difficult.
I always "flick" the starter button to that the motor is either pushed past TDC, or rebounds moving the piston back down the bore--- either way when I next apply the starter the motor can get a little momentum before hitting compression again.
releases would help you out after you solve your problem which may just be the compensator or starter clutch ( Bendix).
tip: do not use air impact tools on the compensator or the clutch hub nut ( left hand thread!). Impacts can knock the magnets off of the rotor, destroying the stator. and the tranny shifter dogs can be pooched.
Mike