Posts by mniron

    I would like to see this swing arm failure discussed a little further. In these photos I see two points of interest that possibly contributed to this failure.

    • I would like to know if the scuff marks on the tire was caused by the failure or were they the result of spinning donuts on a hard surface. If they resulted from high "G" maneuvers, that could have contributed to the swing arm failure.
    • On the lower photo think I see a flaw in the casting of the swing arm. If, indeed, that is a flaw I see, that would be the primary cause of the failure in my opinion.

    I sure would like to get the opinion of some of the more knowledgeable members here.

    I don't think the G-force would break the swing arm, the rear tire breaks traction first unless something was struck from the side. The 2015 Sl models had break away wheels :) .


    I see the same area you mentioned which does look like a flaw. It will be a while to hear the final take on this as Polaris will take at least month to resolve.

    mniron, Are those bushings inserts in the bearings?

    The two #2 bushings locks the ball bearing inner race, frame and angle drive together. The #18 bushing is actually the inner race of the needle bearing of the axle. Minor wear of the #18 bushing would not throw off the alignment noticeably, it would however if the needle bearing failed and bushing worn. There would be noticeable movement in the rear wheel at this point of failure. The #6 bushing locks the right side of the angle drive and frame, it is also the inner race for the needle bearing. The swing arm moves right or left on the #6 bushing by turning the pivot shaft from the drivers side in or out, the ball bearing with the #2 bushings and the #3 snap ring moves the swing arm right or left.

    My prayers go out to them, there may not be a fatality but I would be shocked if there is not some serious injuries. Looks bad, just hope the slingshot got the worst of it and not the occupants.

    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.

    Having had my swing arm off and installed myself, it would be my guess that your issue lies at the angle drive not being square and that is where I would concentrate my efforts. The pivot shaft has a needle bearing on the belt side and a ball bearing on the opposite. The assembly of the pivot shaft, bushings and bearings makes it nearly impossible for there to be a issue in that area. The only issue in the pivot shaft might be the snap ring holding the drivers side bearing, but you stated that the swing arm does move right and left so I doubt this is broke or missing. The first area of suspect in the swing arm would be the needle bearing on the pulley side of the rear axle in which you have made no comment and I assume is in good condition. This bring me back to the angle drive alignment being suspect. I had used lasers to align pulleys and belts on motorcycles and worked very well, especially when doing wide tire change outs. I have not needed to do this as of yet on the slingshot, but I would place a line laser square on the angle drive sprocket and take measurements from the front and back the rear drive pulley. I would prove first the pulleys are not parallel before tearing apart. Your comments does lead me to believe something is wrong in the angle drive area especially when you cannot move the drive forward enough to get the belt tight.

    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.

    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.


    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.

    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.

    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.

    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.

    Part III


    When I got the Slingshot ready to leave Reeds Towing I stopped by their office to see what I owed for storage and taking Mavis to the ER the day before. The response was "Ah, nothing". I told them that was to kind and asked again, same reponse. Was not acceptable to me so I gave the guy $20 and told him to at least give that to the gentleman that took Mavis to the ER. Tuesday, I took the front lowers that I removed apart saving the hood bumpers, bolts, brackets, red wings and Assualt grill. Loaded all the parts including the front lower frame and black spoiler in the trunk of the rental car and headed to the recycling center for disposal. Bill directed me to the recycling center and told me the gal's name at the center was Betty. As I drove in, Betty came out and greeted with an evil eye and ask what I was doing there all the way from Michigan thinking that I was dumping off junk in her facility as I was opening the trunk to the rental car with Michigan plates. I told he that Bill warned me about her and he was sitting the passenger seat. After she saw Bill she soften right up and all was fine! From the recycling center we went to the UPS Store to send the salvaged parts back home to Minnesota.


    On the way back to Bill's, I stopped at Walmart to get some Keurig coffee singles to replace some of what we used the last couple of days. I placed them in his cupboard without his knowledge much to his delight after we were gone. I got things packed ready to get back on the road while Mavis washed the towels and linens to leave Bill's apartment as it was when we arrived. The laundry took a little longer than expected so so I helped Bill repair a high pressure concrete driveway washer and straighten up his garage while Mavis tidied up the house and apartment. This was the least we could do for Bill who was so kind and relieved us of so much in a stressful situation.


    Bill is an 80 year old man in liver failure along with other ailments who lost his wife 10 years earlier. Much to Bill's delight I gave him a cap from SSITS and offered him a ride before we left for Minnesota. I really think it was special to him. Bill is a special friend of ours.