07 Road King Starting Noise
Grand HDF Member
Joined: Jan 2012
Posts: 4,459
Likes: 2,896
From: Oklahoma
The comp isn't necessarily "damaged". The problem comes from the spring (inside a can on the rotor) being too weak to provide the resistance needed to keep the comp movement from bottoming out. Unless something abnormal has happened, you will not see any damage when looking at the installed comp. Other than the sprocket itself, the wear parts are all internal and require disassembly to see. Because the spring is too weak, you will probably see very little wear on the cam and slots. It just isn't adequate for the job, much like trying to open a pop bottle with a tooth pick.
Seasoned HDF Member
Joined: Mar 2021
Posts: 18,475
Likes: 3,723
From: backwoods
The comp isn't necessarily "damaged". The problem comes from the spring (inside a can on the rotor) being too weak to provide the resistance needed to keep the comp movement from bottoming out. Unless something abnormal has happened, you will not see any damage when looking at the installed comp. ck.
Grand HDF Member
Joined: Jan 2012
Posts: 4,459
Likes: 2,896
From: Oklahoma
Did you not "unstack" the compensator parts to see how it works? In the center of the rotor there is a sheet metal cover welded in place that has the spring captured inside. Part of the compensator has that spring press on it to recenter the sprocket piece when there is no load on it. If your machine has already had the compensator upgraded with some version of the Screaming Eagle compensator, the above description will make no sense. You will have the belleville springs (big cupped washers) that stack to make the spring and the outer side of the rotor will be just a flat machined surface. Just noticed you have an 01 machine so I don't know if either description of the compensator or rotor applies to your machine.
Last edited by btsom; Apr 24, 2022 at 10:58 AM.
Seasoned HDF Member
Joined: Mar 2021
Posts: 18,475
Likes: 3,723
From: backwoods
Did you not "unstack" the compensator parts to see how it works? In the center of the rotor there is a sheet metal cover welded in place that has the spring captured inside. Part of the compensator has that spring press on it to recenter the sprocket piece when there is no load on it. If your machine has already had the compensator upgraded with some version of the Screaming Eagle compensator, the above description will make no sense. You will have the belleville springs (big cupped washers) that stack to make the spring and the outer side of the rotor will be just a flat machined surface. Just noticed you have an 01 machine so I don't know if either description of the compensator or rotor applies to your machine.
The rotor is the cover on the other side of the inner primary, that covers the statior. Sprocket seal is inside of stator. Mine is stock from 2007. I have had primary and staor off multiple times, I am not picturing it the way you describe. I am guessing the spring is not really a spring like we normally think of a spring?? Not a coil??
I have an 01 and 07, I have had both apart. Inside primary off and stator removed.
Some people here are talking about taking inner primary off. To do so, you need to remove the compensator first. Sounds like maybe the next revision requires removing stator, which would need you to remove inner primary, unless you grind. I have not tried grinding.
I think of the compensator almost as a three dimension gear
Grand HDF Member
Joined: Jan 2012
Posts: 4,459
Likes: 2,896
From: Oklahoma
I have replaced the original compensator on my 08 Road King with the first version SE comp. That is why I know what the original comp looks like. 70,000 miles later I replaced that unit with the current version so I am familiar with that one also. The compensator acts as a shock absorber between the crank shaft and the transmission to smooth out the power pulses and lessen the strain on both the transmission and the bottom end of the engine.
The stator comes off easily and except for some locating tabs which it clears within the first 1/4 inch of movement when removing, it can easily be maneuvered to clear the primary case. The rotor, on the other hand, is splined to the crankshaft and can only move in and out, not sideways until it clears the crankshaft. Before it clears the crankshaft, it will jam against the inner side of the lip of the primary case so it can't be fully removed unless that lip is ground down just a little (the edge, not the face) or the primary case is loosened or removed.
"I think of the compensator almost as a three dimension gear". I am unable to wrap my head around that, have no idea what you are trying to communicate. Everything that we can handle is 3 dimensional. If you are talking about something on the bottom right side of the engine, that is cam chest/oil pump area and has nothing to do with the compensator. I get the feeling we are talking past each other rather than talking about the same subject. Check out a youtube video on Harley compensator replacement and see if that is what you are trying to talk about. A picture is worth 1000 words. Perhaps someone else understands what you are saying better than I do and he can help you. I'm stumped.
The stator comes off easily and except for some locating tabs which it clears within the first 1/4 inch of movement when removing, it can easily be maneuvered to clear the primary case. The rotor, on the other hand, is splined to the crankshaft and can only move in and out, not sideways until it clears the crankshaft. Before it clears the crankshaft, it will jam against the inner side of the lip of the primary case so it can't be fully removed unless that lip is ground down just a little (the edge, not the face) or the primary case is loosened or removed.
"I think of the compensator almost as a three dimension gear". I am unable to wrap my head around that, have no idea what you are trying to communicate. Everything that we can handle is 3 dimensional. If you are talking about something on the bottom right side of the engine, that is cam chest/oil pump area and has nothing to do with the compensator. I get the feeling we are talking past each other rather than talking about the same subject. Check out a youtube video on Harley compensator replacement and see if that is what you are trying to talk about. A picture is worth 1000 words. Perhaps someone else understands what you are saying better than I do and he can help you. I'm stumped.
Seasoned HDF Member
Joined: Mar 2021
Posts: 18,475
Likes: 3,723
From: backwoods
Last edited by Rounders; Apr 24, 2022 at 09:30 PM.
Seasoned HDF Member
Joined: Mar 2021
Posts: 18,475
Likes: 3,723
From: backwoods
I .
that is cam chest/oil pump area and has nothing to do with the compensator. I get the feeling we are talking past each other rather than talking about the same subject. Check out a youtube video on Harley compensator replacement and see if that is what you are trying to talk about. A picture is worth 1000 words. Perhaps someone else understands what you are saying better than I do and he can help you. I'm stumped.
that is cam chest/oil pump area and has nothing to do with the compensator. I get the feeling we are talking past each other rather than talking about the same subject. Check out a youtube video on Harley compensator replacement and see if that is what you are trying to talk about. A picture is worth 1000 words. Perhaps someone else understands what you are saying better than I do and he can help you. I'm stumped.
I have rebuilt harley engines, top and bottom end. I know the difference between cam shaft and comp. Pinion and sproket sie of engine. I am curious what the failure point people are seeing on the compensators. After one fails, and you inspect it, what looks different from when it left the factory.
Seasoned HDF Member
Joined: Mar 2021
Posts: 18,475
Likes: 3,723
From: backwoods
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
Grand HDF Member
Joined: Jan 2012
Posts: 4,459
Likes: 2,896
From: Oklahoma
The sprocket remains in the same plane with the clutch sprocket. The three spokes of the sprocket rest in that valleys of the three lobe cam which is splined to the drive shaft extension which is likewise splined to the crank shaft. Spring tension on the splined cam tries to force the sprocket spokes back into the center of the valleys each time the two pieces are not in that position. This action creates a "cushion" between the engine crank shaft and the sprocket. My original factory comp spring was too weak to prevent the drive and driven pieces from slamming against their stops. When I removed it there was no heavy wear where I would have expected it, where the drive and driven pieces interfaced. I theorize that is because the spring was weak and I replaced it at about 15,000 miles due to the loud bang on almost every start.
The SE comp also got noisy by 70,000 miles. When looking at that one, there were only standard shiny spots at the cam and sprocket spoke interface where I would have expected the wear. On disassembly I found the splines on the crank shaft extension piece cam drive splines heavily worn. They originally were "V" shaped but about half of each "V" was worn away making the slop I heard as a rattle. Again, the impending failure could not be discovered with out disassembly.
The SE comp also got noisy by 70,000 miles. When looking at that one, there were only standard shiny spots at the cam and sprocket spoke interface where I would have expected the wear. On disassembly I found the splines on the crank shaft extension piece cam drive splines heavily worn. They originally were "V" shaped but about half of each "V" was worn away making the slop I heard as a rattle. Again, the impending failure could not be discovered with out disassembly.
The comp in my '08 went out at around 28,000 miles. I had it at the dealer several times for bad starting noises and they said it was all fine. Ended up breaking the chain, inner primary case, clutch basket and starter shaft. Thankfully it was under warranty but I was still without a bike for a while. I followed the tech's recommendation and had a Hayden tensioner installed. I broke a shoe on the Hayden after 4,000 miles, and it was always noisy but it did it's job otherwise.