2002 road king drivetrain alignment

[oldscoolz]

Quick question. Which way do I need to move my front motormount alignment to correct for abnormal wear (cupping) on the outboard side of my drivebelt?

Here's the background. My '02 FLHRI is at 60k miles with its original drivebelt (I think that's right. I bought the bike with 20k on it and have never put a belt on it). I've noticed some cupping of the outside edge of the drivebelt that has been there for as long as I've owned it. No problems with abnormal sounds, vibration, or how the bike tracks. I've checked the wheel alignment and its Ok.

I'm doing routine winter maintenance and changing my tranny pulley from a 32T to 34T, and with 60k on the bike, I figured I'll change the belt. This would also be a good time to address that issue of drivetrain alignment. It's not bad in terms of how the bike operates, but its a little out of line to get that cupping on the outside edge of the drive belt. All I need to do is change the horizontal axis of engine/tranny a little. Here's the focus of what I'm looking for: 1. Which way do I need to move the horizonal axis of the engine/tranny to correct for abnormal wear on the outside edge of the belt? 2. How far (how many threads on the adjustment linkage) should I move the axis? I'm thinkin this should be a small change of axis, maybe only 2-4 threads on the adjustment linkage.

Thanks.

 

[oldscoolz]

here's a photo of the belt wear

 

[Bodeen]

Rear wheel alignment could also contribute. Check out Jake's video's on alignment. Very informative..

Installation Videos | Glide-Pro USA

 

[dolt]

I'm with Bodeen; check wheel alignment before tinkering with chassis alignment. I have attached a file that specifically addresses checking and adjusting wheel alignment on Harley's. Change pulley and belt and then follow the "string line" alignment procedure and if the chassis is not aligned, you won't be able to align the wheels. If the wheels align, roll up a few miles and see if the belt is still showing signs of cupping. Chassis alignment is not often required and is a much more time consuming and exacting procedure; a last resort. Have you identified what/where the belt is making contact?

 

[fin_676]

I have a few questions/thoughts going through my head on this one
As I have never had a touring model of Harley I am going off how I think it is set up
I am under the impression that the engine gearbox and swing arm being a unit and rubber mounted into the frame with front and rear rubber mounts on the engine and gearbox with the swing arm being mounted by bearings to the gearbox with rubber bushings in the frame to isolate the vibration
Therefore the relationship of the gearbox to swing arm is fixed although a bearing or 2 might be worn allowing for a wee bit of slop
But any drivetrain alignment would not alter the relationship of the gearbox to the swing arm and if this is correct then the only place that there could be an alignment issue is with the rear wheel
However worn swing arm bearings could also cause a wee issue

Brian

 

[oldscoolz]

thanks all. i checked the wheel alignment with the string (fishin line) method and it looks fine.

brain, i'm right with you on your analysis. two questions. how can i check the swingarm bearings without pressin them out of the swingarm? i haven't noticed any slop or play in the swingarm. second, if the engine/tranny/swingarm doesn't have any lateral flex then what is the purpose of the front engine mount linkage adjuster? if that's the case, there should be only one correct place for that front engine mount (at a right angle from the swingarm shaft) and there'd be no reason to ever change that angle.

 

[fin_676]

To check swing arm bearings raise rear wheel off the ground grab rear wheel at furthest point from swing arm and try to move wheel from left to right if there is any slop in the bearings you will feel the movement however any movement could also be from a wheel bearing grab top and bottom of wheel and try to twist it any slop in that bearing will be felt then
I think that drivetrain alignment is to ensure that front and rear wheels are in alignment and on the same vertical alignment
Wear on an edge of the drive belt could be caused by the belt pulleys being out of alignment this is adjusted by use of different spacers behind the front pulley
All this information is taken out of my head based on my experiences and I have never touched a touring Harley so there may be some wrong info

Brian

 

[tourbox]

I had the same wear on my '96 UC as your belt. It turned out to be a rubber flap that was riveted to the belt guard, outside portion, that had been flipped up over the belt when a tire was changed. That belt had 80k on it when I changed it out. It was funny because the rubber flap didn't seem to have any wear on it. I don't know if yours have that flap or not.
tourbox

 

[dolt]

I still want to know what the belt is coming into contact with to trim off the corner of the "teeth" as shown in the picture. Knowing that is the first step to addressing the issue.

Both front and rear wheels can be aligned but the "drive train" may not be aligned in the chassis. The drive train alignment can be adjusted on both the "x" and "y" axis to the chassis. Having the drive train out of alignment can cause handling issues such as the infamous "bagger wobble" and will also cause odd wear patterns and cupping on the rear tire and in more extreme situations could exhibit wear on the edge of the drive belt. However, the wear pattern on the picture the OP posted doesn't appear to be the result of the drive train being out of alignment with the chassis. JMHO and could certainly be proven wrong.

I have attached two photos of the rear wheel on my '02 FLHT. The first photo shows a rear wheel that is aligned with the front but offset in the swing arm. The second photo shows the rear wheel also aligned with the front but now centered in the swing arm after a chassis alignment. The bike used to wobble a bit in a high speed sweeper, say one marked at 50mph but taken at 80mph. After centering the wheel in the swing arm and replacing the rubber "donuts" at the swing arm; the wobble is gone. I think the donuts had more to do with eliminating the wobble than the chassis alignment but not sure.:small3d002:

I doubt that your swing arm bushings are worn to the point that the wear would be the source of the belt wear. However, at 60K miles, I would replace the rubber "donuts" at the swing arm as they will compress .030" to .040" over time and will present high speed handling issues.

As I stated in a previous post, aligning the drive train to the chassis is a time consuming task and requires accurate digital levels and lasers. Jim's does sell a tool for about $400 that eliminates the lasers. There is a drive train to chassis alignment procedure in the service manual but there are other procedures that I prefer to use.

The belt must be making contact with something to exhibit the wear pattern in the OP's photograph. Finding out what/where that contact is taking place is the key to addressing the issue. Where does the belt ride when the wheel is rotated forward? Where does the belt ride when the wheel is rotated backward? What is the belt rubbing on? The OP says he bought the bike with 20K miles on the clock and the belt was showing the wear when he bought the bike, so perhaps the previous owner solved the problem but did not change the belt? If the belt is not making contact with anything but the pulleys, I don't see how pulleys could produce the wear pattern shown in the photo.

 

[oldscoolz]

thanks dolt. sounds like you've been down this road. here are some comments about the cupping wear on the outside of the belt. the manual says that some of this type of wear is not unusual. (6-14 in the manual. "while some bevealing of the outside edge is common, and by itself is not usually harmful, it is an indication of sprocket misalignment."

my belt rides along the outside edge of both the tranny and wheel pulleys. there's no abnormal wear on either pulley. to me, this suggests that there's a shorter distance between the outside edge of the two pulleys than the inside edge. another way to put this is that there alignment is off by the rear wheel being deflected to the right, or the tranny end of the engine/tranny being deflected to the right. this would cause the belt to tend to ride to outside and wear on that side where it first comes into contact with each pulley as it goes round and round.

dolt, u bring up another point. if the rear wheel is dead straight, but not positioned in-line with the tranny pulley, you could get this same kind of belt wear. when you talk about moving the rear wheel in relation to the rear fender, this is another way to line up the pulleys. the types of changes i've been talkin about assume that the pulleys are lined up but not parallel. another possibility is that the pulleys ARE parallel but they're not lined up.

i've previously looked at that possibility and concluded that i shouldn't change the wheel spacers or use a spacer between the wheel and the rear wheel pulley. i actually bought a spacer for the pulley, put it on, and found that i didn't have enough clearance. so i left everything stock back there. like yours, my rear wheel is positioned off center to the left in relation to the rear fender.