Drive Belt / Removal / Tension / Alignement

    Here is all you need to adjust or remove your belt:


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    I haven't tried to adjust the belt alignment using this procedure yet because I can't understand is how these instructions will get the belt to run straight on the rear sprocket.


    1) I lifted the rear wheel and took my hand and pulled the belt sideways toward the passenger side as I rotated the wheel. The belt moved all the way to the drivers side of the angle drive sprocket and and the rear wheel sprocket. When I let go of the belt and just rotated the wheel, the belt immediately moved right back to the left side of the angle drive and rear sprocket until it hit the side lip on the rear sprocket. To me, this tells me the angle drive sprocket is not parallel to the rear sprocket. I've aligned this type of setup on equipment and you have to have both sprockets in as perfect alignment as possible so the belt will track straight on both sprockets.


    2) So my question is, how does turning the cross shaft correct for the parallel alignment of the angle drive or the swing arm? I can see how the cross shaft will move the swing arm left or right but this is not going to move the angle drive since it is bolted to the frame. On motorcycles, the rear wheel is adjusted with the two side adjusters to get the belt to run centered in the rear sprocket by changing the angle of the rear wheel sprocket just enough so both sprockets are parallel to each other. I don't see how this is possible on the slingshot.


    Note: I loosened all of the bolts on angle drive and cross shaft nut and slid the angle drive back as far as it would go and then forward until it hit a stop point. This left the belt a bit on the loose side. I don't know what stops the angle drive from going any more forward on the drive shaft side unless possible the drive shaft itself? I think when I tighten the belt tension nut on the angle drive to get the right amount of tension, it moves the angle drive slightly more forward than the left side and this is causing the belt to run inward on the angle drive sprocket and cause the problem of running against the inside lip of the rear wheel. If some one with technical knowledge of how this cross shaft adjustment really works I would really appreciate it. Also, before I try this, just how do you turn the cross shaft?

    Never kill a perfectly good liver with cheap liquor.

    Figured out how the cross shaft turns. Played around with that but does not fix the problem. Going to have to start playing with shims on the angle drive and see if I can get the belt to run true on the rear sprocket.

    Never kill a perfectly good liver with cheap liquor.

    How did you get the cross shaft toturn. Mine looks like a smooth round hole. Never mind. Found it on the battery side. Seems that the shop manual missed that, as there is no reference to opposite side adjust!

    Belt was really tight on mine and I was finding it impossible to move the wheel assy forward. While setting the bolt torques for adjustment I had a flash. Let the sling move it. I set the adjust torques to 20 and 10 and loosened the adjuster bolt about a half turn. Backed out of the garage about 40 feet or so and did a couple of power starts, with short chirps from back tire. Back into garage and found the assy tight against the adjust bolt. I repeated again to get a lot of slack in the belt. Tomorrow I will slowly adjust to spec. I was afraid to open the adjuster too much for fear of really slamming the assy forward. Figured it was better to move in small increments. So for those needing to get some belt slack, this worked beautifully without having to beat on the sling anymore.
    One other helpful tool is a $13, 25 inch breaker bar from harbor freight.

    FYI, the wheel assembly or the swing arm assembly does not move when adjusting the belt tension, only rhe right angle drive assembly moves. Loosening the swing arm pivot shaft nut and backing off the shaft allows the right angle drive assembly to move within it he oblong shaft hole of the right angle drive. The pivot shaft is locked into the Slingshot frame keeping the swing arm in alignment. Some corrosion does form between the drive assembly and the other pivot components which may make the drive assembly difficult to begin to move, follow the instructions of belt tension as stated. The pivot shaft requires a 22mm Allen socket. The shaft needs to be back out one turn for the angle drive to move freely to adjust. Sometimes understanding what moves while adjusting makes things a little easier. Good luck.

    Edited once, last by mniron: correction ().

    Fixit, I dont know if you have seen the parts breakdown on the Polaris site. If you haven't are pix of the rt angle drive and the swingarm.


    I can see the oval track in the angle drive where the swingarm shaft moves. But the only way I can see for belt position adjustment is if the shoulder on the swingarm cross shaft is not concentric and could change the angle of the swingarm???


    Below are links to the polaris pages. They heve a nice zoom feature to see detail. Hope this helps cause I'm at a loss to explain that adjustment.


    Parts | Polaris Slingshot Store


    Parts | Polaris Slingshot Store

    mniron, does the cv joint then provide the slack for movement of the angle drive? How does turning the cross shaft adjust belt position?


    Thanks for the info. I bought mine used and i've been working through some problems.

    Again, the swing arm does not move as it is locked into the frame, the angle drive moves. This can only be achieved by loosening the pivot nut and the backing out the pivot shaft with a 22mm Allen socket from the opposite end(drivers side). The angle drive then can be move forward to tighten and to the rear to loosen the belt, it also can be angled to align the belt. Maybe by looking into the swing arm removal procedures will better help to understand what I am trying to convey. The only way the swing arm moves other than pivot, something would need to break.

    Edited once, last by mniron: correction ().

    Quote from Roy658

    mniron, does the cv joint then provide the slack for movement of the angle drive? How does turning the cross shaft adjust belt position?


    Thanks for the info. I bought mine used and i've been working through some problems.

    The first question answer is yes, Loosening the pivot shaft by backing out one turn frees the angle drive to be moved. The shaft is turned in tighten the bearings of the shaft along with tightening down on the angle drive, the pivot shaft nut tightens the drive completely and locks the shaft from moving or backing out.

    @Roy658, Sorry, been away for a couple of days at a funeral.


    I've played with trying to get the belt aligned so many times I can now do the belt tension in my sleep I think. I have never had a problem setting the belt tension. Getting the belt aligned however is an ongoing trial and error. To loosen the belt I do it this way:


    1) Loosen the two angle drive mounting bolts
    2) Loosen the angle drive adjusting bolt lock nut
    3) Back off the angle drive adjusting bolt a few turns until it can be turned by hand
    4) Loosen the cross shaft nut on the passenger side until it can be turned by hand


    You can then move the angle drive back if you want to take the belt off. Will have to keep loosening the angle drive adjusting bolt each time you need to slide the angle drive back further.


    To set the belt tension I did learn something about the order in which you tighten all the bolts up that eliminated that loose feeling in the rear tire. I am not sure why it happens or at least on mine it has and I have been able to reproduce it so I know it does work.


    1) Torque the cross shaft to 20 ft lbs or close to it
    2) Snug up the angle drive mounting bolts hand tight. Manual has about 10 ft lbs. Either works.
    3) Tighten the angle drive adjusting nut while you keep checking the belt tension until you get the desired tension you want. I leave mine a little on the loose side. PM me if you want to know why so we don't get off onto another topic. Mainly my personal choice.
    4) Tighten the adjusting bolt lock nut
    5) Torque the cross shaft to 150 ft lbs. (Doing this one first eliminated my loose feeling in the rear tire)
    6) Torque the angle drive mounting bolts to speck
    7) Torque the cross shaft to the 190 ft lbs. That took a 24" cheater bar for me.


    I have not had any problems doing it this way and some may have done it other ways so which ever one works is good.


    My current problem is getting the belt to ride in the center of the rear pulley or as the book says "more to the left side". I've tried turning the cross shaft but it didn't cure the belt alignment on the rear pulley and I am not sure how it can. To me it just seemed more to aligning the rear wheel left or right. No matter what I did with the cross shaft, the belt still runs against the left side of the rear pulley a little to tightly and squeaks, squeals or just makes an aggravating rubbing sound. Hopefully someone with the knowledge and has gotten the belt to run a little more straighter on pulley can chime in with how they did it. In my simple way of thinking, the two pulleys are not running true to each other and I don't see how to change that.

    Never kill a perfectly good liver with cheap liquor.


    Are you backing out the pivot shaft? This is done from the drivers side with a 22mm Allen socket. Also when you torque to 20 pounds, are you torquing from this side or the pivot shaft nut? I ask because your instructions are not clear on those two subjects.

    Edited once, last by mniron: correction ().

    mniron, Thank again. Followed the outline you wrote and though not a pleasant job the result is great. Just took it for a 10 mile test and its quiet! Considering.
    Couldn't find a 22mm allen anywhere so I used an M14 bolt and a couple of 22mm nuts, spot welded the thing together and it worked. They have a nice one on Amazon for 10 bucks that I ordered in case there is a next time.
    Thanks for your time as this old man really needed the education.

    I didn't mess with the pivot shaft when setting the belt tension. Just loosened the pivot shaft nut. I'm not sure why you would need to back out the pivot shaft itself? The angle drive will slide forward and backward without having to turn the pivot shaft from the drivers side to adjust the belt tension or at least mine does. Maybe there is something in that causing the belt alignment problem.


    Now as to the belt alignment, I'm assuming the pivot shaft plays some part in that but so far turning it left or right has not done anything to change the belt from sliding to the inside of the back pulley. I'm probably not seeing what or why this is supposed to correct that. My pivot shaft took a bit of levering to break it free and turn the first time.

    Never kill a perfectly good liver with cheap liquor.

    Quote from FixIt

    I didn't mess with the pivot shaft when setting the belt tension. Just loosened the pivot shaft nut. I'm not sure why you would need to back out the pivot shaft itself? The angle drive will slide forward and backward without having to turn the pivot shaft from the drivers side to adjust the belt tension or at least mine does. Maybe there is something in that causing the belt alignment problem.


    Now as to the belt alignment, I'm assuming the pivot shaft plays some part in that but so far turning it left or right has not done anything to change the belt from sliding to the inside of the back pulley. I'm probably not seeing what or why this is supposed to correct that. My pivot shaft took a bit of levering to break it free and turn the first time.

    Backing off the pivot shaft one turn I believe is to insure the angle drive will move freely back on forth without binding. But in your case you must first correct the belt alignment then adjust the tension. By turning the pivot shaft it moves the entire swing arm assembly to the right by turning it in and to the left by turning it out, pay close attention to Step 5 in the Drive Belt Alignment Adjustment procedure.


    This will aligned your belt, then follow up by following the belt tension procedure and you should be set. I would recommend to follow the entire belt tension procedure step by step including backing out the pivot shaft. I believe some of your problems have been omitted steps. The alignment moves the swing arm right or left with the pivot shaft, the belt tension moves the angle drive forward or backward.


    If you still have problems with the alignment, I would highly recommend a warranty claim if the pulleys are not parallel with each other. Could try to use a laser to check this.

    Edited once, last by mniron: Added comments ().

    Well, I've done the step 5 and saw how it moves the entire wing arm left or right but when I rotate the rear tire doing this the belt moves right back over to the left side of the rear sprocket. All that I was able to see rotating the pivot shaft is that it makes the belt track left or right on the angle drive sprocket but doesn't fix the problem with the belt moving over against the inside of the rear wheel sprocket and rubbing the side of it. I'm starting to think the angle drive mount may be a little out of alignment on the frame. I have found that if I loosen the belt until it is too loose per the instruction the belt will track more to the center of the rear sprocket. It's about to drive me nuts trying to figure this out. From all I can see, the angle drive sprocket and rear wheel sprocket are not parallel to each other and I can't figure out yet how to correct this.

    Never kill a perfectly good liver with cheap liquor.

    Quote from FixIt

    Well, I've done the step 5 and saw how it moves the entire wing arm left or right but when I rotate the rear tire doing this the belt moves right back over to the left side of the rear sprocket. All that I was able to see rotating the pivot shaft is that it makes the belt track left or right on the angle drive sprocket but doesn't fix the problem with the belt moving over against the inside of the rear wheel sprocket and rubbing the side of it. I'm starting to think the angle drive mount may be a little out of alignment on the frame. I have found that if I loosen the belt until it is too loose per the instruction the belt will track more to the center of the rear sprocket. It's about to drive me nuts trying to figure this out. From all I can see, the angle drive sprocket and rear wheel sprocket are not parallel to each other and I can't figure out yet how to correct this.

    I did add a couple of comments to my earlier post, I would give it one last try and follow every step in the procedures no matter if it seems irrelevant. Then if the alignment problem persists, verify with a laser to see that the pulleys are not parallel. If this is the case then it definitely is a warranty issue. It seems like you have a good understanding of how it is supposed to work, it may be very well the alignment is frame related. Please keep us informed.

    That is something I haven't considered. I'm not sure how I can check the alignment of the swing arm to the frame without some special jig set up. I believe the swing arm has bearings on each side. I have seen posts that said they had to replace the swing arm to fix the rear bearing failing which I would assume is a factory machining error.


    The next thing I was thinking to do is to remove the drive shaft and see if moving the angle drive forward to get the belt tension set will let the two sprockets stay aligned with each other. I can only move mine forward so far and it seems to be stopped by the drive shaft but that leaves the belt a little on the loose side. I've been avoiding taking the whole swing arm and angle drive out but that looks like where it is heading.

    Never kill a perfectly good liver with cheap liquor.