After reading about a multitude of belt issues and adjustment problems on this forum (one poor guy was thinking of selling his Thunderbird because of all the belt horror stories he read), the time came to adjust my belt. I had gone past the recommendation of adjusting at 2,500 and took it to 5,000 because even though on the loose side, the belt was performing well. Absolutely no noticeable wear, no chirping and the belt always ran to the outside flange of the wheel pulley. I decided to do everything by the manual the first time, just to see where that got me. Before starting, I bought the belt tension gauge and the wheel alignment tool from Triumph
Prior to adjusting, I measured the wheel alignment using the alignment tool, just to see where the factory had it set. The measurement was 3.048” on the left and right sides. I then tightened the belt, but this is the only thing I didn’t do to factory spec. They recommend a maximum deflection of .350” and I came in at .375, simply because 3/8” was easy to read on the deflection gauge and I decided to err a little on the loose side, since the belt will loosen with use anyway. The wheel alignment wound up at 3.094” on each side. I tightened everything up to factory torque specs, put it all back together and went for a ride. Not surprisingly, the belt performed smoothly, did not chirp and continued to end up against the right flange, just like it did from the factory. I only took a 50 mile ride, but if it goes sour over the next couple of thousand miles, I’ll update this thread.
During the procedure, I inspected every inch of the belt with a high intensity light and it is still looking like new. There were some very slight rub marks (no noticeable wear) on the right edge, not surprising because the belt does rub against it.
On the issue of where the belt is tracking, I think these belts are designed to ride against the flange and trying to get it to ride in the middle with a 1/16” gap on each side is a waste of time. Mine has been against the outside flange for 5K, still looks great, doesn’t chirp and is not showing edge wear. It continues to ride the right flange just as it did from the factory.
On the issue of chirp, I think that this is caused by a belt/pulley misalignment, just as it is in autos. If a belt contacts the edge of the pulley at enough of an angle, it rides up the edge then snaps back down, causing a chirp. This happens quickly and repeatedly, making it sound like you have birds in your back wheel. My guess is that often times, the rear wheel is improperly aligned after belt tightening and the dreaded chirp begins.
This procedure worked for me. If you are having chirp issues, I suggest that before you spend a lot of time and/or money you might want to try and set everything back to the factory spec and then work it from there. Also, I don’t have a clue as to how to check belt alignment unless you have a laser belt alignment tool. I’ve seen these for as low as $50 but can’t vouch for how effective they are.
As always, this is just my experience and opinion. I hope you find it useful.
Prior to adjusting, I measured the wheel alignment using the alignment tool, just to see where the factory had it set. The measurement was 3.048” on the left and right sides. I then tightened the belt, but this is the only thing I didn’t do to factory spec. They recommend a maximum deflection of .350” and I came in at .375, simply because 3/8” was easy to read on the deflection gauge and I decided to err a little on the loose side, since the belt will loosen with use anyway. The wheel alignment wound up at 3.094” on each side. I tightened everything up to factory torque specs, put it all back together and went for a ride. Not surprisingly, the belt performed smoothly, did not chirp and continued to end up against the right flange, just like it did from the factory. I only took a 50 mile ride, but if it goes sour over the next couple of thousand miles, I’ll update this thread.
During the procedure, I inspected every inch of the belt with a high intensity light and it is still looking like new. There were some very slight rub marks (no noticeable wear) on the right edge, not surprising because the belt does rub against it.
On the issue of where the belt is tracking, I think these belts are designed to ride against the flange and trying to get it to ride in the middle with a 1/16” gap on each side is a waste of time. Mine has been against the outside flange for 5K, still looks great, doesn’t chirp and is not showing edge wear. It continues to ride the right flange just as it did from the factory.
On the issue of chirp, I think that this is caused by a belt/pulley misalignment, just as it is in autos. If a belt contacts the edge of the pulley at enough of an angle, it rides up the edge then snaps back down, causing a chirp. This happens quickly and repeatedly, making it sound like you have birds in your back wheel. My guess is that often times, the rear wheel is improperly aligned after belt tightening and the dreaded chirp begins.
This procedure worked for me. If you are having chirp issues, I suggest that before you spend a lot of time and/or money you might want to try and set everything back to the factory spec and then work it from there. Also, I don’t have a clue as to how to check belt alignment unless you have a laser belt alignment tool. I’ve seen these for as low as $50 but can’t vouch for how effective they are.
As always, this is just my experience and opinion. I hope you find it useful.