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Grinding Sound on Start Up

franka

Active Member
2007 mechanically stock Road King with 50,000 miles and impeccable service record. Recently, when starting (random doesn't happen with every start) awful grinding sound culminating with backfire through the air cleaner. Bike always starts after a couple two or three try's and runs perfectly with no issues. Not riding until I find out what it is, any ideas? Starter, pinion gear, bushing etc?
 
You will have to pull your clutch basket check for this. The splines on the inner hub are subject to this noise. They seem to strip out on the back side. As they get worse you get the grinding & kick back problems. See attached pic, item # 10 highlighted in redUntitled 2.jpg
 
The other thing I would be worried about is the nut on the compensator backing out enough to let the rotor wallow around. Trust me, you do not want to let this go for too long. Drain the primary (check the magnet in the plug) and open up the Primary. Check everything in there. If the fluid smells burnt, I would bet your stator has some burnt coils. Have to pull the compensator, clutch basket and chain off so you can pull the rotor. If the compensator nut is loose, inspect the dogs on the hole in the rotor to make sure they are OK. When my compensator nut backed off, the rotor wallowed around enough for the magnets to jam against the stator coils and lock the rotor. The driveshaft sheared off all of the dogs in the rotor hole!!! What a mess!! Needed new rotor and stator.

Cheers,

TQ
 
+1 on TQ's post, basically the same thing happened on my 05 Ultra Classic.
Thank God for extended warranty.
 
First, the most likely cause is the starter clutch getting tired and worn. It is the over run clutch that lets the starter gear that engages the ring gear on the clutch basket spin faster than the starter as the engine catches. It is a sprag clutch that starts to make that noise in the early stages of failure. If you still have the factory compensator, it probably makes an occasional loud metallic bang or crack when you press the starter button. The bang is the compensator slamming against the max travel limit because of a weak spring. That bang puts a heavy shock load on the starter clutch and causes early failure. Mine went out at 15,000 miles. Sometimes a new battery "cures" the grind for a while, but it will return. Unfortunately the only long term fix is to replace the compensator with the latest Harley version or an after market different design. Baker has one that most like pretty well but it is more expensive than the Harley compensator. Both will require a new rotor, the current one is not compatible with either new compensator. Finally the list is completed with a replacement starter drive. "Allballs" makes a popular one which has worked well for me about 8 years. You are far from the first person with an 07 0r 08 96 ci engine who has needed to change these parts. Few others have gotten 50,000 on the factory equipment as you have. There are many pictorials and videos on net for the compensator change if you are one who likes to do his own work. If not, you will at least see what the old and new parts look like. Harley didn't upgrade the compensators from the factory until the '11 model year and that early version comp has its own set of problems. The latest version seems to be doing pretty well and that is all that Harley sells now. If you hear a "growl" as the engine comes to a stop at shut down, you probably need a new inner primary bearing also. I believe that the inner primary bearing is also damaged by the compensator slamming against its stop. Wish it was better, less expensive news, but many have had the symptoms you describe and the above is the fix.
 
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Sorry for the delay in updating all of you who offered suggestions on what the issue could be. Turned out to be both the starter motor and the compensator spring pack. However, since we had the primary open and the bike has 50K miles on it we also replaced the clutch assembly, compensator, and inner primary and race bearing. Amazing how much quitter everything is down there and how much smoother it shifts gears, feels like a new bike!
 
I have done that work myself and know what the parts ran. I am curious if you had the work done at a shop, how much the labor was.
 
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