Loose Drive Belt

    Saw a Sam post on belts and it got me thinking to check my tension since I recently (mileage wise) had the rear bearings replaced. The dealer I used seemed to like tight belts so I figured mine would probably be too tight. Lifting the rear wheel off the ground and applying 10 lbs of pressure yields a movement over an inch, which is way too loose according to Slingshot repair manual (should be .4 in). Strange part to me is that when the rear wheel is on the ground the belt is as tight as a piano spring. We all know that a too tight belt is rough on bearings and I would assume that the risk of a loose belt is track movement or popping off. With it tight on the ground its not coming off and checking and rechecking the track, it doesn't appear to be moving. What am I missing here? What's the downside to a loose belt? Why do we check with the rear wheel off the ground when we run it with the rear wheel on the ground?

    Quote from airoutlaw

    Roll the sling forward and backward to find the tightest belt area... tension check there. Chances are you won't find a detectable difference in the tightness.

    I never really thought about that possibility with the belt. It is definitely something we look/watch for on the race bike chain.


    Tim "Ghost" Ganey
    Winfield, Alabama
    205spam412spam2868

    Since purchasing our SlingShot three years ago there has been quite a bit of amateur anecdotal evidence offered concerning the drive belt tension, mostly on loosening it, but very very little actual "scientific" evidence. In my continuing research I have been becoming more and more convinced that Polaris, and Gates, really do understand the concept of proper belt tightness where tight, (not too tight, mind you), is better than loose. Thus the reasoning why I have returned to keeping our belt tension near factory specs.



    Bill

    Quote from Flybuddy

    Saw a Sam post on belts and it got me thinking to check my tension since I recently (mileage wise) had the rear bearings replaced. The dealer I used seemed to like tight belts so I figured mine would probably be too tight. Lifting the rear wheel off the ground and applying 10 lbs of pressure yields a movement over an inch, which is way too loose according to Slingshot repair manual (should be .4 in). Strange part to me is that when the rear wheel is on the ground the belt is as tight as a piano spring. We all know that a too tight belt is rough on bearings and I would assume that the risk of a loose belt is track movement or popping off. With it tight on the ground its not coming off and checking and rechecking the track, it doesn't appear to be moving. What am I missing here? What's the downside to a loose belt? Why do we check with the rear wheel off the ground when we run it with the rear wheel on the ground?

    @Flybuddy, you do not lift the rear wheel off the ground at the frame. the wheel needs to be raises to spin the wheel for the tightest spot at the swing arm at the back. The Belt is not check for tension with swing arm in the down position. Yes, if you raise the sling at the frame, the swing arm will lower to the lowest point of the shock. The belt will be very loose. This not the way to check for the tension. You do need to spin the wheel, but the way I have found to do this is to place my "Motorcycle Jack rail" under the back edge of the swing arm. I will post a video of this here. If you made any adjustments with the belt in the position described, you will have a way too tight belt. Again, the reason for raising the wheel is to find the tightest point on the belt and pulley. That is where you want to check the belt tension and make adjustments. I hope all will read this.


    My motorcycle Jack is the Yellow device I have at the Back Wheel. I describe how and where I raise the Slingshot. If you do it anywhere else the drive belt is not in the position for checking belt tension.


    @Flybuddy, there are two independent adjustments for the belt. They do not interfere with each other. First, you have Belt Alignment, this is where the belt rides on the rear pulley. The second is belt tension, this is how much deflection is there in the belt when 10 lbs of pressure is placed on the belt. Each adjustment is different and use different bolts to make the adjustments. Now there is one bolt that is common to both adjustments, the Pivot Bolt, the main swing arm pivot point. This bold is loosened for both adjustment. You must look at the whole video for each adjustment procedure and follow the adjustments and I hope it will guide you to a successful adjustment. If you have questions, I be glad to answer and help with anything that is not clear. These are more difficult adjustment to perform and should not be needed all the time. Before making any adjustment to a belt, it is very important to understand what is happening with the adjustment. The swing arm has a travel throughtout the full range of the shock. The arch is not proportional, so there are points that may be tighter than others in the travel. The normal ride is with the belt in the most extended point, so that is where the adjustment should be checked. This is what has to be thought about when instructions are given. Sometime the instruction of raising the wheel may not be clearly understood as to where to do this. Anytime a question like that comes up, seak a more clear understanding about that point. I want to help all folks issues such as this.