A friend just got a 01 road king, carbed and it's had the 96" kit installed. The bike starts fine when it's cold but after riding a few miles and shutting it off it will fire off but makes a clanking sound then shuts off. It will start fine the second try. Other than the kit and se slip ons we don't know what's been done. It has 22k miles and we trying to find a starting point. The battery tested fine and from reading it sounds like a possible compensator problem. Is their anyway to check that or any other suggestions?

 

My first question is how old is your battery. The engine when cold is looser, the metal is contracted and the engine has a little less compression. When hot everything is expanded and tighter. More compression.

What you are describing is the first tail tell of a battery getting weaker. It has enough juice to turn the motor over with the engine cold but is fighting to turn it over when hot.

The noise is from the compensator kicking back because the starter doesn't have enough battery power to push it through a compression stroke which it where the engine usually stops. The reason it starts fine the second time is it has kicked back off the compression stroke enough to give the starter a running start on the compression stroke.

This is not the only possible cause but it is the first to check.

 

The older compensators (like this one) don't typically come apart, but instead the nut backs off. Most likely not the problem in this case because the noise wouldn't be there then gone.

 

The battery is 2.5 years old. We took it to autozone and had it load tested and they said it was fine.

 

Anybody?

 

Maybe the starter clutch failing... I had similar happen, it wouldn't totally zing back out but it would make some clunky sounds. I think that was an $80.00 part....

 

With electrical things, testing them is only part of the story. If that battery is that age, but hasn't been kept on a smart charger while not being ridden, and isn't ridden at least weekly, I would agree with the folks that the battery is weak.

Sometimes, there is no accurate diagnosis available, and ya gotsta take the 'shotgun approach'. The engineers among us will try to work it to death with diagnosing, but sometimes, that's just what it boils down to.

In this case, if you suspect that the compensator is the problem and want to start with that rather than a new battery, it's time to get dirty...take off the primary cover and take a peek.

 

History shows that the old style compensators worked well through the 88 ci engines but were not up to the forces generated by the 96 ci engines. Now that your buddy's machine is a 96, there is a good chance the compensator is going through the same slow failure seen on the 07 through 10 production machines. The spring has a tendency to slowly weaken to the point that there is little to no tension in the center of compensator movement allowing a "rattle" back and forth between unloaded extremes. Then comes a loud metallic crack or bang when engaging the starter when the compensator is abruptly slammed against its movement limit.

Diagnosing a noise on the internet is always tough and risky. You might well be better off to pay for an experienced ear before dropping $400 to $500 on a new comp and learn that isn't the real problem.

 

What is strange is, it shuts off? Are ya saying it actually starts and runs with the clanking noise then shuts off? Or does it just fire/pop make noise and stop? If it is the latter my guess is ya raised the cranking compression with the 96 kit and without compression releases it is "kicking back". A good way to destroy the starter drive and/or starter.

 

Man, truer words have never been spoken! To me, it sometimes seems like folks spend more time on the net looking for an easy fix or other miracle that just doin' it the old school way...get a couple of leads on what the problem might be, and just tear into it and see what you find!