Went out (2003 FLSTC) Sunday and noticed some knocking at a stop light, at idle. To me I thought it might have been piston slap or wrist pin slap as it got less and less the warmer it got. However, jumping out the spark plugs one at a time didn't get rid of it, making wrist pin slap more likely of the two.

When cold raising the RPM, the exhaust masked the sound but it is still there. When warm, higher than idle RPM and you can't hear the knock.

When I took it to the dealer and had my guy look at it and ruled out cam compartment issues and says he doesn't think that it is piston or wrist pin slap. He didn't know what it was, but the only thing he really mentioned was the counter balancer. My worry is connecting rod bearings, as I believe that requires the flywheel assembly to be replaced, at a cost of $1000.

When my guy looked it over he took a bunch of measurements. He did mention that the crank runout was 'good'. I don't how that would apply to the connecting rod bearings.

How likely might this be a connecting rod / flywheel issue do you think? Are they common? I can't seem to find occurrences of failures.

My concern is that it's going to be close to a grand to tear it down and investigate already. Another grand or so to buy a flywheel assembly and we are close to 2500 total when everything is all done.

Thanks for reading.

-Rick

 

I am rebuilding my crankshaft right now because of rod bearings. 5 years ago when the bike had 10k miles on it, it spun a wrist pin bushing. Mine are tapered. Yours are not. I had to get my crank rebuilt because of this. Now it is 40k miles later and just last week I tore my engine down and found bad rod bearings. Yes the crank must come out to repair that. If it is wrist pin bushings, you could do that on the bike. The crank assembly is rebuildable but I would guess HD doesn't say that. After you determine that is the problem, I would contact Darkhorse crankworks. They can lead you in the right direction. Or maybe that was my problem. There are others that rebuild them too. Good luck.

 

You might as well look at the HD LongBlock Program.

TC88 - $3750
TC95 - $4150

 

Check your compensator nut before you do anything expensive. Mine sounded like hell, turned out to be nothing but a loose nut. I could move it with my fingers...

 

Wow , bummer

 

Thanks everyone, dealer said he thought it might be balancer or rod bearing. Worst case scenario was going to $3500. Me and the wife decided to trade it in on a 2008 Ultra Classic.

Very different bike but I like it.

Thanks again!