Polaris Slingshot Forum banner
1 - 15 of 15 Posts

·
Registered
Joined
·
113 Posts
Discussion Starter · #1 ·
Sorry to resurrect an old and tired topic, but I feel I should share. Haven’t been on here in a while, maybe someone else has discovered this too. I’ve tried everything, clean it often with soap and water, I’ve adjusted it every which way, sometimes it’s pretty good for quite a while. It tends to ride towards the right(outside) of the sprocket. Occasionally you have to drive on dirt or gravel, like in a parking lot, it starts squealing right away.
Recently I tried rubbing a bar of soap on the outside edge of the belt. Eureka! It was quiet all day! Now I keep a scrap of bar soap in a baggie in the glove box. If it hollers, we stop for a minute and give it a rub. I think soap is pretty benign, don’t want to use any oils or other harsh chemicals…
 

·
Registered
Joined
·
3,009 Posts
Recently I tried rubbing a bar of soap on the outside edge of the belt. Eureka! It was quiet all day! Now I keep a scrap of bar soap in a baggie in the glove box. If it hollers, we stop for a minute and give it a rub. I think soap is pretty benign, don’t want to use any oils or other harsh chemicals…
Sounds benign enough to me. Once I made the mistake of starting to mess with the belt of our 2015 in the first place, it took several years of frustrating trial and error to finally find it's "sweet spot" again. If most were to look at our belt position today they would say that it is adjusted too far to the left, where it appears to be riding upon the inside lip at rest. However, I have figured out that our belt wants to walk towards the right, or outside, while under power, so obviously it is riding upon the inside lip only until power is applied. Being adjusted in this way now must be allowing enough room so it does not walk far enough towards the outside so to rub on that lip, and thus squeal. Also I have figured out that the looser the belt, the noisier it typically becomes and I am thinking that this is because the looser belt tends to walk more? So what I finally hit upon by accident here is to adjust our belt to near factory specs after a ride on a hot day. By doing it this way I am assuring that this will be the tightest the belt will ever become, (keeping in mind that the belt gets tighter the warmer it gets.) With how our belt is finally adjusted today, I no longer need to constantly lube it and I only need to take a scrub brush after it every several thousand miles or so to keep it quiet, even when operating where it is dusty.

A final note of possible interest is that if readers have not picked up on it, for the OP and myself it has been the belt coming into contact with the outside lip which has been giving us the most grief. Has anybody noticed that with the later models that Polaris has eliminated this outside lip? Coincidence?

Bill

Added note: Since commenting here I became curious and checked that our garage is at 70 degrees and belt deflection is a little over 0.8 inches.I originally adjusted the belt after a ride at around 100 degrees to approximately 0.65 inches.
 

·
Registered
Joined
·
113 Posts
Discussion Starter · #3 ·
Thanks for that info Bill. I had to replace the clicking rear wheel bearing a couple years ago and it was a challenge to get the tension and alignment adjustments to a good spot. Took the SS to Arizona with us last winter, it’s a lot more dusty there than up here in Seattle. I got tired of cleaning the belt almost every day. I use a bottle jack under the swingarm so I can spin the wheel while cleaning.
 

·
Registered
Joined
·
208 Posts
A SS tech told me to just spray a dry lube product on the belt when it started to get noisy. That seems to work for about 2,500 miles then it needs another spray
 
Joined
·
616 Posts
Sorry to resurrect an old and tired topic, but I feel I should share. Haven’t been on here in a while, maybe someone else has discovered this too. I’ve tried everything, clean it often with soap and water, I’ve adjusted it every which way, sometimes it’s pretty good for quite a while. It tends to ride towards the right(outside) of the sprocket. Occasionally you have to drive on dirt or gravel, like in a parking lot, it starts squealing right away.
Recently I tried rubbing a bar of soap on the outside edge of the belt. Eureka! It was quiet all day! Now I keep a scrap of bar soap in a baggie in the glove box. If it hollers, we stop for a minute and give it a rub. I think soap is pretty benign, don’t want to use any oils or other harsh chemicals…
Hi @Firewrench! This is a very valid topic, and there's a lot to absorb and understand here.

Let's start with belt alignment and tension. The specified alignment location for the belt is to the inside (left side) of pulley. If you're running to the right, it should be re-aligned. The process for doing so isn't complex, but it does require specific tools, as does adjustment of the belt tension.

Are you down with learning how to do it yourself? I'd be happy to guide you if so.
 

·
Registered
Joined
·
113 Posts
Discussion Starter · #6 ·
Hi @Firewrench! This is a very valid topic, and there's a lot to absorb and understand here.

Let's start with belt alignment and tension. The specified alignment location for the belt is to the inside (left side) of pulley. If you're running to the right, it should be re-aligned. The process for doing so isn't complex, but it does require specific tools, as does adjustment of the belt tension.

Are you down with learning how to do it yourself? I'd be happy to guide you if so.
Sure. I have the shop manual and the big Allen socket. The manual is a little confusing…
It don’t think it tracks “severely” to the right, I’ve followed behind on my Harley to watch it track.
If you can explain it better than the manual, I’m all ears!
Thanks!
I think I have the tension pretty close.
 
Joined
·
616 Posts
Sure. I have the shop manual and the big Allen socket. The manual is a little confusing…
It don’t think it tracks “severely” to the right, I’ve followed behind on my Harley to watch it track.
If you can explain it better than the manual, I’m all ears!
Thanks!
I think I have the tension pretty close.
What's interesting about the alignment adjustment is that it is literally designed to flex the chassis to affect the position/angle of the angle drive. The chassis casting in that region is intended to allow this flex via its large openings.

Loosening the swingarm pivot nut allows one to turn the big 22mm Allen in (clockwise) which flexes the chassis on the right until the belt tracks to the left side of the pulley. Of course, the large swingarm pivot nut on the right side must be loosened first to afford this adjustment, then tightened afterwards to 190 foot lbs.

Sometimes a fair amount of force is required to get the angularity needed. This adjustment is best done with the rear wheel off the ground so one can spin the rear wheel and assess the adjustment and its resultant belt alignment.

Bear in mind that as you perform this adjustment, belt tension is also affected. The farther you turn the big Allen in, the tighter the belt will get. Are you familiar with the actual belt tension adjustment and how to perform it?
 

·
Registered
Joined
·
113 Posts
Discussion Starter · #8 ·
I’d have to re-read the manual, I think I remember you have to loosen the bolts that hold the angle drive? IIRC, I couldn’t get the angle drive to move much. It’s been a few moons ago…

also I thought that spinning the wheel by hand isn’t the same as having it driven by the engine.
 
Joined
·
616 Posts
I’d have to re-read the manual, I think I remember you have to loosen the bolts that hold the angle drive? IIRC, I couldn’t get the angle drive to move much. It’s been a few moons ago…

also I thought that spinning the wheel by hand isn’t the same as having it driven by the engine.
First, of course, we must remove the black plastic access panel concealing the drive sprocket.

Yes, the mounting bolts need to be loosened, they are 18mm heads just above and below the leading edge of the pulley. They fit in slotted holes for movement. Forward of that area, an adjusting nut (also 18mm) allows one to either relax the angle drive rearward or pull it forward to achieve the correct tension. The nut is accessible by a box wrench from underneath, or a deepwell socket from inside the cockpit, as a hole is provided there for access. The deepwell also works well to get the two bolts loose/tight, as it clears the sprocket well. Of course, having the swingarm pivot axle loose also removes that clamping tension from the rear of the angle drive, which is needed for belt tension adjustment.

The belt alignment is a matter of geometry, so it behaves the same loaded or unloaded. Tightening the swingarm axle with the big Allen will move the rear of the angle drive to the right; the resultant angularity change of the drive sprocket moves the belt to the left. This will also tighten the belt as it also slightly extends the difference between centers of the two pulleys, so being able to adjust the belt tension is rather synonymous to adjusting its alignment on the drive pulley.

Run the Allen in like 1/4 turn at a time and spin the wheel. Repeat as needed until the belt is riding to the left (inboard) side of drive sprocket. Then adjust belt tension.

I have some useful detail about belt tension as well. Let's cover that when you are ready to dive in with your tools!
 

·
Registered
Joined
·
113 Posts
Discussion Starter · #10 ·
Thank you Bill! I almost feel like I’m getting a personal instruction session…
Your explanation makes a lot more sense than the manual.
I’m ready to give it another try. I’ll try to find time this weekend and report back. I’ll measure the belt deflection afterwards.
I understand the belt gets tighter when hot.
 

·
Registered
Joined
·
113 Posts
Discussion Starter · #11 ·
Bill, you are the Man! Your instructions made it easy. I think I was too tentative asjusting the 22mm allen. I ended up turning it in about 5/8 of a turn. I moved it a quarter turn 3 times, until the belt was riding hard to the left. I put a jackstand under the wheel hub and let it down so the weight was on it like its sitting on the ground. Ran it in first gear and watched the belt. I moved the big allen out 1/8 of a turn, now it’s riding “gently” to the left. Belt deflection is just over 3/4”.
When I tried adjusting tension before, I didn’t know you had to have the pivot locknut loose. Now I know. I’ll snug up the belt a tad and go for a spin.
Thank you! Thank you!
 
Joined
·
616 Posts
Bill, you are the Man! Your instructions made it easy. I think I was too tentative asjusting the 22mm allen. I ended up turning it in about 5/8 of a turn. I moved it a quarter turn 3 times, until the belt was riding hard to the left. I put a jackstand under the wheel hub and let it down so the weight was on it like its sitting on the ground. Ran it in first gear and watched the belt. I moved the big allen out 1/8 of a turn, now it’s riding “gently” to the left. Belt deflection is just over 3/4”.
When I tried adjusting tension before, I didn’t know you had to have the pivot locknut loose. Now I know. I’ll snug up the belt a tad and go for a spin.
Thank you! Thank you!
Wow that's wonderful to hear! I'm pleased you found this informative. Hopefully others will too. I'm also going to put all this info in a descriptive video to help the community.

A couple more aspects regarding belt tension:

Yes, as you mentioned, heat plays a part. We will usually set the belt on the loose side, for especially down here in Florida, the heat of operation will expand the swingarm sufficiently that the belt will be too tight if adjusted to stock spec cold. All that engine heat ends up flowing under the machine and goes right othe swingarm, whcih as a large aluminum casting, absorbs it like a sponge. We've studied this effect in action; the difference in tension from cold to hot can be startling.

Load also plays a part, for when the suspension compresses, the belt is tightened, another result of the geometry. We will put a driver in the machine when we check belt tension. If the machine is usually toting two people, we will put two people. If the machine is typically loaded down with cargo, well - you get the idea.

So our basic approach is to set it at about 3/4" slack cold, with the appropriate load in the machine. This allows a bit of leeway for the inevitable tightening that will occur when the swingarm warms and expands.

This overall method of belt alignment and tension adjustment has proven to consistently provide the quietest, smoothest operation while also removing the stress from the axle bearing that a too-tight belt produces. When the suspension is uncompressed from load and the swingarm is cold, it will actually seem too loose. Don't sweat it. All the involved parts play together much better on the loose side than the over-tight side.

Now you know what I know about this critical region after 6 years of Slingshot husbandry. I have scrutinized, experimented, observed and adapted until arriving at this process. It never fails to satisfy :)
 

·
Registered
Joined
·
113 Posts
Discussion Starter · #13 ·
Took it for a spin, about 3 miles, it “sounds” great! No sound!
Re-checked deflection, closer to 3/4”, we don’t have the severe heat here in Seattle. So I think we’re in good shape.
Thanks again for sharing your expertise. Greatly appreciated!
 

·
Registered
Joined
·
3,009 Posts
What's interesting about the alignment adjustment is that it is literally designed to flex the chassis to affect the position/angle of the angle drive. The chassis casting in that region is intended to allow this flex via its large openings.
This is an interesting statement to me where over the years I have come to understand adjusting the alignment of the drive belt necessitated pushing the angle drive left or right. I do not recall ever reading anything where the frame is being flexed to accomplish this task? Here I thought I had finally came to understand all of this and now I am all confused again?

Bill
 
Joined
·
616 Posts
This is an interesting statement to me where over the years I have come to understand adjusting the alignment of the drive belt necessitated pushing the angle drive left or right. I do not recall ever reading anything where the frame is being flexed to accomplish this task? Here I thought I had finally came to understand all of this and now I am all confused again?

Bill
Yessir, that's what's happening. The adjustment is actually one of angularity, which is why it's also critical to reducing belt noise. Only the rear of the angle drive is being shifted, right or left so as to accomplish the correct angle.

When the belt rides to the left edge of the drive sprocket via this method, the centerlines of the angle drive output shaft and the driven rear wheel sprocket/rear axle are as close to parallel as possible, in so achieving the ideal arrangement for quiet belt operation and longest wear.
 
1 - 15 of 15 Posts
Top