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Discussion Starter · #1 ·
my dealer is struggling to remount my oem hugger without having the rear tire rub it inside.

the hugger had been installed when the bike was delivered and no rubbing problem ever existed until the dealer changed out my front sprocket, going from 19T to 18T about 10k miles ago. In the process, I simply agreed to leave the hugger off and have ridden it that way for another 10K or so.

Now, I'm changing my chain and rear sprocket (from 43T oem to 45T) and have asked that my oem hugger be reinstalled, thinking that now, with a new chain (112 link cuttable to 110 or 108) there should be plenty of room and adjustment space to allow for the hugger.

But, guess what? They called to report that the rub is still there-- about a 6" rub along the inner centerline of the hugger from near the inside, bottom, front of the hugger along an arc upward and rearward. The depth of the rub is pretty shallow but still noticeable. Naturally, when the tire heats and expands, this could become worse.

They also tell me that even at the farthest rearward point that the axle can move back that the rub is still there.

My thought is that the only thing that could be causing this is that at some point now or earlier, a tech reversed the concentric on the rear axle, which might account for enough change in height of the axle within the slider that it is causing the rub-- ie the axle is now riding higher in the adjuster slide than it had and that is the cause of the rub. It would seem that the size of sprockets, etc. is having no bearing on this. It was all fine until the dealer mounted a different front sprocket, or perhaps this might have occured during a tire change at some other time. Either way, I cannot understand why a rub would now occur if it was never there before, especially if the wheel can move all the way aft and still have the rub.

Anyone out there have a thought on this, or better yet, actual experience with this problem? thanks very much.

If it is the concentric-- anyone know if having it reversed would cause this problem, cause any other issues, such as damage to axle, bearings, drive train, etc.? and, most importantly, whether you can detect an out of position concentric visually or not? Finally, how much distance would the axle move upward if the concentric were reversed 180?
 

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2004 Daytona 955i, 2018 Indian Roadmaster, 1980 CB650C in resto
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Are you using the stock tire size?
 

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Discussion Starter · #3 ·
short answer is, yes.

I've been thru many tires but have always checked to be sure they measure w/in a very small tolerance difference of the oem tires. In general, and per the manufacturers' detailed sizing charts, all tires I've used, e.g. Dunlop Qualifiers, Pirelli Corsas, etc. are all virtually the same exact diameters, profiles, types, etc. as the oem's and have always used the oem and recommended sizes.

Today, the dealer discovered that by leaving on the standard chain guard and then mounting the hugger w/o it's provided chain guard, that the hugger no longer rubs, although it's a very close tolerance. This "fix" still may not prevent the rub, once the tires are at operating temperature though, so I'll need to ride it to verify that. It also allows the hugger to slightly flex and vibrate but may be ok nevertheless. A fix for that may be to drill the chain guard for the two attaching bolts that would connect the hugger to the chain guard and bolt it as was designed for it's provided chain guard. Again, this further highlights why this is such an odd occurence as the hugger originally was mounted when the bike was purchased new and never rubbed until the dealer got into sprocket changes and one would think that it's provided chain guard would have been configured to keep the hugger in the right position, and I know that it did. There is no sign of wear around the two bolt holes on the original chain guard or the hugger that would have allowed either to shift position, so it's still a mystery to me why this has occured.

I first went from an oem 19T to a JT 18T, keeping the oem 43T rear. That should have reduced the amount of chain spacing needed in front and not introduced any tolerance issue, yet according to the dealer it did and they even decided they'd have to cut the oem chain, from 108 to 106 in order to make all that work ( a little shorter swing arm may have made it steer a little quicker too, so no big issue there).

Now, with the chain and rear sprocket needing replacement anyway, I've elected to replace the front sprocket again, but w/an oem 18T(outrageous at $75) and try out a 45T rear with it. This required using a 112 link chain, which was cut to 110, and a clip link installed instead of a rivet link, so I can re-gear if I don't like the result. My alternate is a 44T rear, which may then take the chain to 108, which would be back to the oem chain size at that point.

I suspect, I'll end up going with the 44 rear, at which point I'll rivet the link and keep it that way.

My goal here has been to have the hugger protect the new Penske rear shock and spring that I mounted about 10k mi ago (better late than never I guess). And, to see if I can optimize throttle response, acceleration, handling, etc.

I'll take it to the track tomorrow for a lapping day and see how it all works out.

Thanks for the feedback and any further thoughts, anecdotes, etc.
 

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The concentric on the ST and I presume you have a single side swingarm on your RS can be adjusted in the wrong direction. Here are some of the things that happen when this is done.

The bike leans REALLY FAR over when on the side stand.
The seat is much shorter / bike is less tall.
The wheel is mounted higher because the axle mount is raised to the top of the arc on the swing arm.

This is likely your issue. Tell the dealer to turn the concentric adjuster the other direction (after loosening the lock bolt) and the hugger should fit again.

Good luck, hope this fixes things for you.
 
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