2nd session of belt gymnastics

[ButterSmooth]

In an effort to not hijack the "burning rubber smell' thread, thought I'd post my belt adventures here.

Today was my second session of belt tweaking -- I'm moving slowly, but making improvements. The belt is no longer riding on the front pulley outboard flange and on my first test it was about 2mm off the rear flange. It has since moved back toward the rear flange and a little off-center in the front.

The tension was more interesting. Started out at 210# (Krikit II) and #C (33Hz), 3/8 of a turn (CCW) on the adjuster produced A (27Hz). That should be about 160# on the Krikit, but it indicated 195# at the loose spot and 205# at the tight spot. I could twist the belt more than 90°, which in my Harley and Indian belt experience indicates a loose belt. At this point I trust the frequency measurement more than the Krikit, so when the rain stops, I'll give it a test ride.

Re-torquing the axle was another adventure. I have a socket that fits inside the muffler, eliminating some of the hassle of the task. But, my gosh 166# is a lot of force. Last time I did it, but this time I quit at 150#. And the muffler mount bolt must be secured with red loctite -- couldn't touch it with an 18" bar.

[PinkRosePetal]

How did you manage to get your belt to not ride the outside flange on your front sprocket?

[IdahoMtnSpyder]

According to BRP TSB a few years ago tension is not critical, except don't have it too tight or too loose. I don't remember the numbers. As for tracking just make sure it tracks between the flange and outer edge of the rear pulley. Don't worry about the front unless it's really riding hard against the flange. In that case you probably have a problem with the engine not being correctly mounted in the frame. The belt will move a lot during riding, and especially when you back up. The best time to check the belt alignment is after riding some distance and stopping while still going forward.

As for the rear axle torque get a torque wrench extender. Amazon has several. Search for 36 mm harley or vw wrench. With it you can easily get the 166 lb-in torque with a 120 lb-in wrench and getting a wrench onto the nut is no problem. Just watch to make sure the axle doesn't creep forward when you torque the nut. I have that problem but most do not.

[ButterSmooth]

PinkRosePetal, belt dynamics and steering are kind of strange. The rear pulley steers the belt left and right (outside, inside) on the front pulley. If you move the adjusters to steer the belt to the inside, it will also move the belt to the outside of the rear pulley, correcting both alignment problems. Tightening the right adjuster (the driver's right) or loosening the left adjuster steers the belt off of the outside flange of the front pulley. Of course you have to keep the tension adjusted correctly for all this. And the belt alignment changes when you actually ride -- that's why I'm moving slowly with this, getting in good test rides between adjustments.

[ButterSmooth]

...
As for the rear axle torque get a torque wrench extender. Amazon has several. Search for 36 mm harley or vw wrench. With it you can easily get the 166 lb-in torque with a 120 lb-in wrench and getting a wrench onto the nut is no problem. Just watch to make sure the axle doesn't creep forward when you torque the nut. I have that problem but most do not.

I've got a 250lbf torque wrench that's 2' long, so getting 166 lbf isn't a problem. It's just that my built-in 'something-is-going-to-break' alarm starts going off at about 150 lbf.

I seem to remember a line in the manual that says, '...the belt must not contact the front pulley flanges...', but maybe that's not right. I yield to your experience with Spyders, I am a newbie.

[IdahoMtnSpyder]

And the belt alignment changes when you actually ride -- that's why I'm moving slowly with this, getting in good test rides between adjustments.

If you're brave and confident jack up the Spyder, tie down the front wheels, and run it through the forward gears. Quicker than going for a test ride. Also, it's best to check belt tension with the rear tire off the ground. That way it hangs all the way at the bottom of the shock every time you check and adjust. The belt tension varies as the rear wheel moves up and down so off ground readings are more consistent check to check.

You will, of course, get a VSS error since the front wheels aren't turning, but that clears as soon as you start riding.

[ButterSmooth]

If you're brave and confident jack up the Spyder, tie down the front wheels, and run it through the forward gears. Quicker than going for a test ride. Also, it's best to check belt tension with the rear tire off the ground. That way it hangs all the way at the bottom of the shock every time you check and adjust. The belt tension varies as the rear wheel moves up and down so off ground readings are more consistent check to check.

You will, of course, get a VSS error since the front wheels aren't turning, but that clears as soon as you start riding.

Since Murphy is my guardian angel, I'm not brave enough to run my Spyder tied down in any way. I did that once to adjust the belt tracking on my Indian Scout and escaped unscathed. But the alignment still changed when ridden, due I think to suspension movement and frame/swing-arm alignment variances. Having an RT without auto-leveling suspension of the 'L', the rear shock is at full extension when on the ground or jacked up. I've tested the tension in both cases and it is the same. I'm not in a hurry to get this task 'checked off the list', and since the as-delivered alignment has worked for 3000 miles, making small corrections to improve the alignment and hopefully reduce vibration doesn't endanger the belt or anything else. I've watched videos of 'live' alignments and it makes the process look trivial. Still need to ride for a while to see what changes, though.

[Possible]

Unless the drive pulley is inline with the pivot point of the swingarm, the tension on the belt will change as the swingarm pivots. It shouldn't be
the same on the ground, as in the air. It will be tighter on the ground as the swingarm has pivoted as the shock/spring is compressed. Mine went
from 160-180 lb. in the air to 180-200 lb. on the ground.

Good idea to take it slow. I set mine to 0.84" in the air. I reset the tension at the same time, and all was well for a couple weeks. It has since moved
back to near, but not against the flange, about 0.010" now.

[ButterSmooth]

Unless the drive pulley is inline with the pivot point of the swingarm, the tension on the belt will change as the swingarm pivots.

Absolutely.

It shouldn't be the same on the ground, as in the air. It will be tighter on the ground as the swingarm has pivoted as the shock/spring is compressed. Mine went from 160-180 lb. in the air to 180-200 lb. on the ground.

The air spring on the RT keeps the suspension at full extension at any pressure above 50#, so mine doesn't change. I'd imagine you could do the same on the RTL by adding air to the spring -- as long as you don't turn on the key. If you do, the auto ride height will kick in and take the pressure down.

Good idea to take it slow. I set mine to 0.84" in the air. I reset the tension at the same time, and all was well for a couple weeks. It has since moved
back to near, but not against the flange, about 0.010" now.

Always different after some miles, in my experience.

[Possible]

Aha, I hadn't considered the self adjusting suspension.

[ButterSmooth]

I wanted to give this thread a poke because I'm still concerned about the difference in results between the Krikit and a frequency meter. With the meter the tension/alignment adjusters work just like tuning a string (in this case a string bass). It's very sensitive to changes, while the Krikit almost seems immune. Using the Krikit seems simple and straight forward, but I must be doing something to influence it's readings. Any thoughts?

[Possible]

Just an amendment: I hadn't realized I had been backing into the garage, which I understand can affect the belt tracking. So I drove
straight in tonight, and the belt distance from the flange measures 0.079". So now I've very happy.

I think the Kriket II works very well, It shows the difference between the tightness of the belt when we first got it, and then after
loosening the tension about 1/2 turn. And the difference between on the ground and in the air. Why do you feel you're influencing the
readings?

[IdahoMtnSpyder]

I hadn't realized I had been backing into the garage, which I understand can affect the belt tracking.

Not CAN, DOES!!!!!!!

[MONK]

The air spring on the RT keeps the suspension at full extension at any pressure above 50#...

So, are you saying that any increase in air pressure over 50# is useless? The owners manual (some fine folks here) said for my weight, I should run about 65#. If the add'l 15# doesn't matter, why am I doing this?

Not doubting you but curious as I feel I may be missing something.

[BLUEKNIGHT911]

I wanted to give this thread a poke because I'm still concerned about the difference in results between the Krikit and a frequency meter. With the meter the tension/alignment adjusters work just like tuning a string (in this case a string bass). It's very sensitive to changes, while the Krikit almost seems immune. Using the Krikit seems simple and straight forward, but I must be doing something to influence it's readings. Any thoughts?

The KritKit gauge Tells you to put it in the Middle of the belt. There's a reason for that !!! .... Otherwise it would say " put the D**n gauge anywhere you want .... sounds pretty simple to me ..... good luck .... Mike

[ButterSmooth]

So, are you saying that any increase in air pressure over 50# is useless? The owners manual (some fine folks here) said for my weight, I should run about 65#. If the add'l 15# doesn't matter, why am I doing this?

Not doubting you but curious as I feel I may be missing something.

NO not at all. Without any weight on the machine 50# tops out the suspension. When you get on, with your chosen pressure, the ride height settles to the desired position. The 50#+ thing is only true for an unloaded RT.

[ButterSmooth]

Just an amendment: I hadn't realized I had been backing into the garage, which I understand can affect the belt tracking. So I drove
straight in tonight, and the belt distance from the flange measures 0.079". So now I've very happy.

I think the Kriket II works very well, It shows the difference between the tightness of the belt when we first got it, and then after
loosening the tension about 1/2 turn. And the difference between on the ground and in the air. Why do you feel you're influencing the
readings?

For some reason the Krikit doesn't register changes in tension with as much sensitivity as the harmonic meter. I suspect the most fallible part of the measuring system - me.

[ButterSmooth]

I went for a 65 mile test ride today, after my rainy day maintenance -- the belt tweaks and the 3000 mile service. Changed to a full synthetic 5w-40 MA2 oil. The shifts are quieter now, but the big changes are attributable to the belt tension and alignment. The 42 to 52 mph whine has been reduced by about 50% and I can hear the exhaust tone now. The GRONK that accompanied starting out from a stop is gone. The vibration in the 60-70 mph range is much reduced and what remains is from the front tires, I think.

All this improvement and the belt isn't right yet. At the end of the ride the belt was again against the inner rear flange. I think the 160#, 28Hz is the place to stay with the tension, as I continue to move the alignment further from the rear flange. I'll continue to move it out 2mm and then ride and recheck.

[Possible]

I don't want to hijack this thread, but what the heck is that GRONK that I hear occasionally when starting out? Most noticeable if
I have backed up, and then started back forward again. Doesn't happen often enough to be annoying, just curious.

[ButterSmooth]

I don't want to hijack this thread, but what the heck is that GRONK that I hear occasionally when starting out? Most noticeable if
I have backed up, and then started back forward again. Doesn't happen often enough to be annoying, just curious.

Let me qualify this first -- my answer is pure speculation, based on my GRONK and the fact that it has gone away. I think it has something to do with the belt trying to climb up the front pulley flanges and chattering down. Since I've aligned my belt away from the flange, it no longer happens. But you make a good point; Since reversing moves the belt, it may return if I try reverse, then forward. Before alignment, mine did it every time leaving a stop.

[Possible]

Very good idea. I hadn't considered the fact that the belt does move around when changing direction. That certainly makes sense. Thank you.

[BLUEKNIGHT911]

Very good idea. I hadn't considered the fact that the belt does move around when changing direction. That certainly makes sense. Thank you.

Not only in reverse but whenever the belt is in motion ..... years ago there was a video posted on this Forum by one of the members. .... it showed the rear sprocket and the drive belt while the Spyder was being driven on the road ..... the belt was moving back and forth on the sprocket teeth ... continuously..... After I saw that video, I stopped being concerned about minor changes in Exactly where the belt was on the Sprocket when the Spyder was stopped ..... good luck .... Mike

[Possible]

That certainly would be reasonable. And a good reason to ensure the belt is properly situated on the sprocket if possible. Seems to me
that if the belt is moving around while riding, then it would be more likely to try and climb the flange is it starts out up against the flange.
If it starts out in a neutral position it's more likely to run centered. Especially when you consider that, generally, it seems to maintain the
set clearance over time.

But JMO of course.

[ButterSmooth]

...
If it starts out in a neutral position it's more likely to run centered. Especially when you consider that, generally, it seems to maintain the
set clearance over time. ...

I have very little belt experience on the Spyder, as indicated by the thread title. I did, however, battle extensively with my Scout (Indian wars?). Chassis stiffness seems to be the big driver in belt position stability. Go around a left corner and look at the belt, then go around a right corner and look at the belt -- very different results. Go down a rough road and look again -- another different result.

The only reasonable approach is to start with the belt in the most neutral position (centered in front, with some flange clearance in the back) and then mostly forget about it. When you know you've rolled to a straight stop (like in the garage), glance at it once in a while, but don't be obsessive. You should always visually inspect your machine as a force of habit -- it's amazing how many potential problems are avoided with a simple look.

[Possible]

I can't say about the Indian, but Harley's have a flange on both sides of their belt pulleys, because they have a rubber mounted swingarm and
keeping strict alignment is impossible.