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I have noticed on my bike, as well as several pictures of other k1200lts online that the rear tire isn't centered with the dressing i.e. rear fender, saddle bags, and trunk?

I had thought at first that my frame must have been tweaked by a P.O., but when I saw that the majority of the rear pics I could find on the internet showed the same results: rear tire being approximately 1" right of center I thought that it must have been a manufacturing flaw, or something that an engineer thought would better balance the bike.


I was reading through a tire thread when I came across a post that may have answered a question I have had about rear end alignment.

The rear Dunlop had a history of rubbing against the Driveshaft Housing/Swingarm unless you added an additional spacer ring/shim like the one that is already there.

HTH,

John
Am I understanding this post correctly? Is there a spacer between the wheel, and the final drive? and if so is the thickness by any chance 1/2", or more likely 12mm?

I have yet to take off my rear wheel, but I noticed the offset while pondering a hitch install.

Thanks in advance for the help! Dale
 

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There is a spacer between the rear wheel and the final drive, but it is only about 1.6mm thick, definitely not even close to 12mm. The purpose of the spacer probably has nothing to do with wheel alignment, but rather to insulate the aluminum wheel from the aluminum drive flange.
 
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There is a spacer between the rear wheel and the final drive, but it is only about 1.6mm thick, definitely not even close to 12mm. The purpose of the spacer probably has nothing to do with wheel alignment, but rather to insulate the aluminum wheel from the aluminum drive flange to prevent the effects of corrosion.
This makes sense because I've seen the effects of galvanic corrosion, and the little amount of time that it takes for it to set in especially when road salts are present.

Does this mean that my rear/sub frame is tweaked in the same manner as nearly every other rear picture of a k1200lt that is on the net?

I thought I was just seeing what I wanted to see until I asked a neutral party at work (who is a construction worker) to put his eye on the images, and he saw the same pattern, a consistent 1"right of center.

Do any of you readers have this issue?
 

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I forgot to install that spacer once, as a result the wheel rubbed the swing arm leaving a fine mark on the wheel (all away around)
 

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There is a spacer between the rear wheel and the final drive, but it is only about 1.6mm thick, definitely not even close to 12mm. The purpose of the spacer probably has nothing to do with wheel alignment, but rather to insulate the aluminum wheel from the aluminum drive flange.
Why would you need to insulate between the same materials?
 

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aluminium molecule gives up one electron to corrode easier than steel does so aluminium will protect the steel although no where near as well as zinc which gives up electrons quite freely
 
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I don't have my manual handy, butt the rear wheel/ track offset is engineered in. There is a procedure in the book about how to set up the measuring jigs to get the offset correct. I don't know the dimensions, butt someone with a book can look that up and post. BTW, again I'm not sure, but most two wheel vehicles will have an engineered offset.
 

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Correct Dick, the rear wheel is offset to the front wheel centreline by 4mm according to the BMW workshop manual (in fact there is a range stated), and yes, there is a procedure for checking alignment & offset. As for the steel spacer and all those electrons, well,.... maybe the same factory technician the over-shimmed all those FD units also took too much off the steel boss on the end of the FD carrier and they had to throw a spacer in there ;)
 

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On the earlier bikes, some makes of tires rubbed the swingarm, even with the standard 2.00 MM spacer in place. BMW supplied 3MM spacers to use in these cases.
 

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So it's not necessarily abnormal for my rear tire to be a half inch right of center?
I would so it's alright as a visual, but if you wanna know if it's within the offset specs, you'll need to follow the manual's procedure for track off-set. Plus you want measurements taken relative to the bike's suspension parts, frame and wheel run-out and NOT the tupperware parts.
 

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I would so it's alright as a visual, but if you wanna know if it's within the offset specs, you'll need to follow the manual's procedure for track off-set. Plus you want measurements taken relative to the bike's suspension parts, frame and wheel run-out and NOT the tupperware parts.
Yes, I would be more suspect of the alignment of the bodywork than of the wheel.
 

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It is by design, that is why they handle so well...
 

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It is by design, that is why they handle so well...
That shows the offset range to be between 5 MM right of center to 14 MM left of center. The original poster states his is considerably to the RIGHT, so something is quite wrong with his bike.

Edit: The picture is misleading. Looking at the formula I see that the range is actually 5 MM LEFT of center to 14 MM RIGHT of center. So the wheel can be over 1/2" to the right, and still be in spec.
 
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That shows the offset range to be between 5 MM right of center to 14 MM left of center. The original poster states his is considerably to the RIGHT, so something is quite wrong with his bike.

Edit: The picture is misleading. Looking at the formula I see that the range is actually 5 MM LEFT of center to 14 MM RIGHT of center. So the wheel can be over 1/2" to the right, and still be in spec.
We don't know that anything is wrong with his bike's wheel alignment. The diagram posted is only addressing relative alignment between front and rear wheels. I see no absolute reference to the bike itself. The OP is referencing to the body work which is a very tenuous reference at best.

To know if anything is wrong, he needs to check the alignment between the wheels as in the diagram. I don't know if BMW has a reference to the frame or depends on the front wheel being centered in the fork and serving as the reference. This seems unlikely as bent forks would mess up that reference. Seems like there must be a frame or engine reference somewhere.
 

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The OP sounds like he is referencing pictures for the alignment in comparison to the body work and pictures can be very misleading.
 

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Discussion Starter #19
The OP sounds like he is referencing pictures for the alignment in comparison to the body work and pictures can be very misleading.
It's true that pictures can be misleading, but out of multiple pictures I saw more that duplicated my concern, few that looked centered, and none that were to the left side.
 

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Well, I just went and looked. My wheel looks centered to me.

Many years ago when I rode an FLH, I had a mishap one evening that tweaked the frame just a little. After replacing the obviously bent parts like fenders, crash bars, handle bars and gas tanks I went for a ride. It handled a little odd, not real bad, it was rideable but I decided to fix it right. Got the frame spec from the manufacturer after some trouble. Stripped it down to the frame ( a whole lot easier than doing that to an LT) and went to measuring. The steering head was twisted to one side. Straightened it to factory spec and put it together. It tracked better than it ever had ( I had it since new), tires wore evenly but it developed another oddity. At the time I lived in Nebraska and the only cruise control we had was the throttle lock, could ride for many miles without touching the handle bars. But. After the repair, if you came off of a bridge and it had a drop off, it would develop a wobble that slowly got worse, best fix was to give it a little throttle and you were good to the next bridge/overpass.

Motorcycle frames have a fairly wide range of specification. If they handle OK and the tires wear OK, be happy and ride it.
 
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