Rear Belt Drive- Alignment and Tracking : V-Twin Forum: Harley Davidson Forums

ramcr913 · 12-09-2012, 09:12 PM

I am building a mild chop (build thread in chopper section) and am in the process of lining the belt up. It is looking pretty good, I can roll the wheel forward and backward and the belt tracks true. The belt is centered on the rear pulley, and is close to centered on the transmission pulley. The question is- should the belt ride the flange on the transmission pulley? Here is what it looks like-
After adjusting the axle, the belt stays centered on the rear pulley:

The belt is just to the inboard of center on the transmission pulley:

The belt has plenty of room relative to the swingarm and frame to move to the outboard side. It only clears the tire by about 3/16":

I have searched this forum and a few others; some say to let the belt run wherever it wants, as long as it clears everything. Others say that their HD service manual says to run the belt outboard to the transmission flange. My instinct is to space the rear pulley just enough to give a little more belt-to-tire clearance.
Opinions...?

mark p · 12-10-2012, 10:25 AM

Go with your gut, outboard is better but what you have going looks better then some I've seen even on some stock bikes.

ramcr913 · 12-11-2012, 08:53 PM

Mark- yeah I think I am going to move the pulley over with a 1/8" spacer. That will give the tire a bit more clearance and put the belt pretty much in the center of the drive pulley, and no flange wear on the side of the belt.
Thanks for the input

Rollmeaway · 12-11-2012, 09:57 PM

I have always ran mine at the flange, depending on your frame & belt guard clearance & thats if your running a guard I would up the spacer to 1/4" that way you would have 7/16'' clearance at the tire. I have seen modified bikes which only have 1/8'' clearance at the tire & run without any hitches.

I say why slim up on the spacer at an 1/8'' & go to a half way point which will get you closer to the flange. If I am reading your scale right in your picture it is showing 7/16 to the flange. If you were to go to a 1/4'' spacer that would be a 1/16'' over half way & on the safe side away from the tire, but again providing you have the extra clearance at the frame.

It would still leave you 3/16'' to the flange which is a comfortable space for adjustment.

hardheaded · 12-12-2012, 09:08 AM

your trans pulley is made so that the belt will ride to the out side flange when bike is rolled forward and inboard when it's rolled back.if you are on a softail frame you should center wheel from center of swingarm bearings.wheel should track slightly to outside flange when rolling forward,very light scuffing on outside of belt.been running mine like this for many years.

Mohead1 · 12-12-2012, 10:45 AM

I center the wheel like "hardheaded" says, then roll the belt and watch how it runs, forward and back. Then if necessary, turn adjuster nut/screw one flat either way to center it in the rear pulley. Let the tranny side ride where it likes, then lock it down and check everything

hardheaded · 12-12-2012, 03:20 PM

mohead 1 is right 1 flat at a time it's very touchy,this is the way to get alot of miles out of your belt ,take the time to get it dead on.

ramcr913 · 12-12-2012, 07:02 PM

Yeah, I already have it adjusted it to ride in the center of the rear pulley, as Mohead and Hardheaded suggested. I intend to finalize this drive with the belt still not touching any flange at all if I can help it.
Rollmeaway, good points made... and I will mock up the belt guard this weekend and see where we're at with it.
One thing though- rolling the wheel forward and backward does not track the belt side to side on the transmission pulley at all. It is not a stock HD pulley, it is the Ultima pulley that came with the tranny. I had a new BDL pulley on a different bike last year, and as long as the belt was centered in the rear pulley it didn't track side to side either.
Thanks all, for the replies. I appreciate the insight.

hardheaded · 12-13-2012, 08:26 AM

Quote:

Originally Posted by ramcr913

Yeah, I already have it adjusted it to ride in the center of the rear pulley, as Mohead and Hardheaded suggested. I intend to finalize this drive with the belt still not touching any flange at all if I can help it.
Rollmeaway, good points made... and I will mock up the belt guard this weekend and see where we're at with it.
One thing though- rolling the wheel forward and backward does not track the belt side to side on the transmission pulley at all. It is not a stock HD pulley, it is the Ultima pulley that came with the tranny. I had a new BDL pulley on a different bike last year, and as long as the belt was centered in the rear pulley it didn't track side to side either.
Thanks all, for the replies. I appreciate the insight.

that's kind of weird because all harley pulley track to the outside rolling forward worder why after market is different?

ramcr913 · 12-14-2012, 03:08 PM

Hardheaded- no idea why the aftermarket pulleys would be different. I can pull the belt to either side of the transmission pulley, and it will promptly track back to where it is in the picture, regardless of which way I spin the back wheel. I kinda like it, no pulley contact on the side of the belt.

Rollmeaway · 12-14-2012, 08:31 PM

There is no difference whether it's RC, PM or OEM once the trans & pulley are aligned with the rear axle ajusters they all track the same. What will alter the position of the belt on the trans drive is the spacing of the rear pulley to the rear wheel hub.

Been down this road & it is very precise providing the rear adjusters are equally torqued & the wheel is parrallel to the swingarm.