Chain rubbing tire

Mitch81special

XS650 Enthusiast
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Hi all
This isn't somthing i'v seen before so just hoping to get a more experienced opinion. Iv got an 81 special and It seems like my chain occasionally makes contact with my tire. I'm guessing it's only when leaning the bike over in a sharp curve. As it is there's maybe a 1/8" - 1/4" clearance. Is this somthing to be concerned with? Is there anything I should be checking? Is there any adjustment for this? Tires are dunlop 130-90 16
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Hey Mitch---Looks like the wheel may be cocked. The axle adjusters on both sides need to be the same , you need to measure the adjusting bolt. Also there are hash marks on the swing arm above the adjuster and a scribe mark on the adjuster, again both sides need to be the same......

tim
 
A pic of the right side adjuster may be helpful......

tim
 
It looks about even but you must measure the length of the bolt in the rear of the adjuster.....

tim
 
Swing arm bushings shot.......?????

tim
 
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Yes, check the play in your rear wheel to check the swing arm bushings. Put it on the center stand and grab the wheel at 3 O'clock (at the very back). Push pull. Does it have much play?
However, it does look like your wheel is out of alignment.
 
Checked the play in the swing arm as yamadude mentioned, I don't feel any play. I measured the bolt and made the adjustment, it was only off by about 3mm. Also my manual says that spindle nut should be torqued to 108 ft lbs? Is that right? Seems like alot.
 
Checked the play in the swing arm as yamadude mentioned, I don't feel any play. I measured the bolt and made the adjustment, it was only off by about 3mm. Also my manual says that spindle nut should be torqued to 108 ft lbs? Is that right? Seems like alot.
Yes, it needs a good deal of torque. Exact torque is not critical.
How does it look after 3mm adjustment?
 
I have an '82 and an '83 Special. Just got down on my hands and knees in the garage.
I've got about 4mm more clearance than you on both of my bikes.
 
See how your chain rollers are wearing only on one side? Means your sprockets are misaligned. Either the tire is cocked off to one side or your wheel spacers are wrong.... and have been for a while now.


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Best way I know to check rear wheel misalignment is the get to about 35-40mph on a flat straight road (if it's crowned, run in the center) and take your hands off the bars. if the bike starts turning left, the rear wheel is cocked to the right... and vise versa. Fine tuning that way is more accurate than trying to measure.
Of course, this assumes everything else on the bike is straight... frame, forks etc.
 
If the wear indicator and the amount that the adjuster nut needs to be tightened on the brake rod are any indication, it may be time you consider getting some new rear brake shoes. At the very least, for the time being, I'd re-position the brake arm on the splined shaft. Rotate it clockwise one or two splines, whatever it takes to get better positioning of the adjuster nut on the brake rod .....

full
 
Hi all
This isn't somthing i'v seen before so just hoping to get a more experienced opinion. Iv got an 81 special and It seems like my chain occasionally makes contact with my tire. I'm guessing it's only when leaning the bike over in a sharp curve. As it is there's maybe a 1/8" - 1/4" clearance. Is this something to be concerned with? Is there anything I should be checking? Is there any adjustment for this? Tires are dunlop 130-90 16View attachment 191101 View attachment 191102

Hi Mitch,
it's more like something you have to live with.
The XS650's stylists swapped the Standard's 4"-18 rear tire to the Special's 5"-16 rear tire but weren't allowed to change anything else in that area.
Note that the only thing that differentiates between a Standard and a Special is the rear shock angle. Everything else can be changed from each to other by swapping parts.
Which is why a Special's 5" tire has a shoe-horn tight fit. It's swingarm was designed to fit a Standard's 4" tire.
Also your bike's rear axle is set just about all the way forward. Is the chain too short (should be 104 links)
or does your rear sprocket have more than the stock 34 teeth on it?
And yeah, your rear axle nut's cotter pin is installed sideways.
The pin's loop end should drop into the castle-nut's slot with one tail clipped short and bent back
over the nut's flat and t'other tail bent forward and across the axle bolt's tail.
 
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