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CVO Technical => Drive Train => Topic started by: Aussie on February 23, 2018, 05:46:05 AM
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Drive belt finally needed re-tensioning, before undoing anything I placed some tape on axle adjustment cams to monitor how much the axle needed to be rotated to get the correct tension.
Original tension was set by dealer 6 Year’s ago”. Although I do a routine check at each service interval.
What I found was after re-tensioning the belt cam washers were in a different location to each other.
Left side +2mm Right side -5mm
Procedure I use to set drive belt tension,
Loosen axle nut.
Push wheel forward to release any tension on belt.
Re-tighten axle nut to 20nm.
Rotate axle using welded nut on left side until correct tension is achieved.
Pictures of tape show the variation after adjustment was made.
Left side +2mm adjustment.
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Right side -5mm from original location
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Rotating rear wheel several rotations to check belt to pull alignment and belt now runs close to centre of pully.
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Close up of belt alignment to pully.
To double check wheel alignment I use the string line method I have been using for years only I measure to the rim and not the tires.
Alignment between front and rear wheel is .040” (1mm), that’s nearly perfect.
Not sure how the Dealer adjusted the belt tension to get the cam washers in the position they were.
Removed the axle nut to check back lash of the adjustment lobe to axle on right side only and found the cam washer was quite loose rocking back and forth on the axle in a radial direction.
Now the questions are,
How accurate is the rear wheel cam adjustment?
Has the MOCO made allowance in the manufacture of the swing arm for the loose fit of the cam washers to axle, hence the cams being in a different position?
Where should the belt track on the pully, left side or centre?
Has there been a service bullitin on the belt adjustment, FLHX is 1/4”-7/16” (4.6-11.1mm) in the service manual, seems a little tight to me. Set mine at 3/8” (9.5mm).
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that is with 12 inch shocks if you changed your to 13 inch shocks that maybe why it seamed tight
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Has there been a service bullitin on the belt adjustment, FLHX is 1/4”-7/16” (4.6-11.1mm) in the service manual, seems a little tight to me. Set mine at 3/8” (9.5mm).
Actually the spec for 2012 was changed from the spec for 2007-2011 models. Those were 1/4" - 5/16" (always gave me a chuckle, since +/- 1/32" is a tighter tolerance than Harley has for some mechanical parts). As you noted, for 2012 they opened that up a bit to 1/4" - 7/16". At 3/8" you are still within the new range so it should be fine.
As for the method Harley uses on Touring models to set rear wheel alignment and tension, it was obviously not designed for precision. I always assumed it was more about making it easier for them to quickly assemble the bikes. We get a lot of complaints around here about strange tracking and tire wear, and the first thing most of us recommend is to check actual wheel alignment (measure) and not assume Harley's system is even close. Your example here is evidence of that.
Jerry
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Actually the spec for 2012 was changed from the spec for 2007-2011 models. Those were 1/4" - 5/16" (always gave me a chuckle, since +/- 1/32" is a tighter tolerance than Harley has for some mechanical parts). As you noted, for 2012 they opened that up a bit to 1/4" - 7/16". At 3/8" you are still within the new range so it should be fine.
As for the method Harley uses on Touring models to set rear wheel alignment and tension, it was obviously not designed for precision. I always assumed it was more about making it easier for them to quickly assemble the bikes. We get a lot of complaints around here about strange tracking and tire wear, and the first thing most of us recommend is to check actual wheel alignment (measure) and not assume Harley's system is even close. Your example here is evidence of that.
Jerry
Left side of belt was running along side of pully.
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Never ceases to amaze me how informative and helpful people are and willing to give a hand. I know when I changed tires on my '13 last summer I marked the original spots with a marker and tape. Went back pretty close. Def a lot easier than my old 2000 ultra. I did have cupping on my orig back tire though.
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After a test ride to check belt tracking I pulled up and belt was back to the left side of pully but not fully against pully edge.
On my return home belt was in centre again.
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I had the same problem when I had the rear tyre replaced. After getting it home I checked the belt tension (didn't trust the shop putting the correct tension on) it was way loose, after getting the correct tension on I run it briefly with the wheel off the ground and found the same thing you had (belt off center). I didn't notice if it was off center before I started, most likely was.
The right cam lobe had play and as you didn't pull the wheel back the same amount.
I sorted out by using a welding rod bent it over at one end and butted up on the bottom swing arm shaft cover plate bolt and used a felt marker to mark the rod at the centre of the left axle shaft, then on the right side ( with the axle just snugged up to hold it) put the rod on the same bolt on the other shaft cover plate and tapped the cam till the shaft center aligned with the mark. Briefly run the wheel again and the belt centered.
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I use the rod method on my FatBoy having to adjust the rear wheel alignment with adjustable bolts on either side of the axle and belt runs the same as my Street Glide.
I was surprised to see the cam washers on my Street Glide had so much radial play that’s why I used the string line method to double check to see if wheel alignment was correct.
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I use the rod method on my FatBoy having to adjust the rear wheel alignment with adjustable bolts on either side of the axle and belt runs the same as my Street Glide.
I was surprised to see the cam washers on my Street Glide had so much radial play that’s why I used the string line method to double check to see if wheel alignment was correct.
I never understood why Harley went away from the adjustable bolts on each side they use on everything else for those useless cams on the Touring models. I think I still have the rod I made back in 1999 for my Dyna, with a 90° bend on one end that went into a hole on the swingarm and a moveable piece that I lined up with the center of the axle. The only problem with that system is that as long as the swingarm pivots on rubber bushings you still don't have the greatest precision. Still beats the crap out of the cam system though. The straightedge/string/laser methods are the best way to go.
Jerry