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It is almost too late for this tire but why would it wear on only one side and not the other? 2002 K1200RS if it matters.
 

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Actually, front tires wear unevenly on all motorcycles due to the fact that during outside turns the tire travels much farther on that side than it does on inside turns. Of course, if you live in Kansas, you might be able to wear out the middle first!
 

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If you read the manual carefully you'll realise that the rear wheel is offset.That contributes to the slight pull to the right generally found on the K1200RS and also uneven front tire wear.

Took me a while to figure that one out and why my left arm/elbow hurt after long days on the road.7-800 km or more per day and countersteering through all that.

So I took the rear wheel spacer out.Front tire still wears left but way less than before and my elbow pain disappeared.
 
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It's the radius of the turn. On the outside lane, the wider radius causes more wear on that side of the tire (the left side in the U.S. and most countries that drive on the right side of the road.) The bike is leaned over longer in a left turn that a right turn. That results in more wear on that side of the tire. Happens to some degree on any motorcycle. I will admit that the K bike has a forward weight bias that is hard on front tires. Mine would cup a sport-touring tire to the point of irritation in about 2500 miles. Didn't seem to matter what brand of tire or the inflation psi. The steering would get so heavy, I'd end up replacing the front with more tread left on it than I might on another type of motorcycle. The tele-lever fork geometry might have something to do with it as well.
 

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If you read the manual carefully you'll realise that the rear wheel is offset.That contributes to the slight pull to the right generally found on the K1200RS and also uneven front tire wear.

Took me a while to figure that one out and why my left arm/elbow hurt after long days on the road.7-800 km or more per day and countersteering through all that.

So I took the rear wheel spacer out.Front tire still wears left but way less than before and my elbow pain disappeared.
Hi H96669. Is this really true about the offset of the front and rear tires? When I first got my 2003 K1200GT, I kept drifting or maybe it was just turns to the left vs the right were noticeably different. I commented to my son-in-law a seasoned rider. His explanation was on me being right handed making my turns seem different, that and a new rider skills. Anyway, I don't notice it now, but I am very curious about your tire offset statement. Regards John
 

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Mr.jrmull....rear wheel offset spec is in the manual.I don't have it with me but the spec isn't set to a single measurement.BMW spec will be Minimum to Maximum and if I remember the difference between min/max is rather large?

Meaning that some bikes will have more offset than others.There is somewhere on the internet a procedure by an engineer who removed the offset.Very involved as he had to build an alignment jig and calculate but he successfully fixed his bike and got rid of the uneven tire wear.

I have the link somewhere but I am a long way from my computer.Unless I remember where that was it will have to wait until late September.

Rear wheel offset is directly related to the drifting to the right and although most won't notice we are always countersteering even on straight roads.Front tire will wear left because of that and my left elbow also suffered.

Easy check? Set cruise control at 60mph and let go of the handlebars?All I can say is that I corrected most but not all the drift to the right when I removed the rear wheel spacer.Better front tire wear pattern and most importantly relieved the tension on my left elbow from the constant countersteering.

Rear wheel spacer is somewhere in my shop.Never going back on and I should have removed it 250,000km ago.

I can't speak for other bikes but there could be a clearance issue without the spacer.Them 3 little Torx bolts holding the ABS ring in place may touch the wheel?But not in my case....2mm clearance.

K100RS.....R100GS....No wheel offset on them. I could lock the throttle and go for miles in a straight line with hands off the handlebars.And never wore out the front tire on the left first.
 

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Mr.jrmull....rear wheel offset spec is in the manual.I don't have it with me but the spec isn't set to a single measurement.BMW spec will be Minimum to Maximum and if I remember the difference between min/max is rather large?
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Rear wheel spacer is somewhere in my shop.Never going back on and I should have removed it 250,000km ago.

I can't speak for other bikes but there could be a clearance issue without the spacer.Them 3 little Torx bolts holding the ABS ring in place may touch the wheel?But not in my case....2mm clearance.
A long time ago at about 50,000 KM, I also removed the rear wheel spacer to reduce the offset. Like yours, from this point on my "pull-to-the-right" was reduced to almost nil. Since this, I have ridden 100,000 KM with many changes of tire brands and the correction is still stable.

HOWEVER, as you have posted, ANYONE who intends to do this must be aware of certain RISKS if you have the 5.00 inch rim:
1) on K1200RS once the spacer is removed the wheel can only be installed in one specific position (out of 4 possible rotation position). Otherwise one of the small bolts of the rear brake rotors (holding ABS speed sensor) will hit the wheel casting and cause a "potential" crooked install.

The above "wheel install" issue was discussed a few times on the now defunct I-BMW forum. The 3 attached pictures will help visualize / check proper install without a spacer.

2) In some countries, in case of an critical accident related to handling/control, you could be liable of riding a modified motorcycle. Someone could argue the factory installed this spacer on all K1200RS for a good reason (and it was missing on yours).

3) I cannot suggest that you try this on your K1200RS - what has worked for me might NOT work for you and MAY cause dangerous handling - you have been warned ;-)


WHAT ARE these SPECS: As you have posted above, the specs allowed are much larger for Offset to the left (front wheel can be 14 mm LEFT of rear wheel centerline). On the opposite, the offset to the right allowed is only 5 mm (front wheel is right of Rear centerline). See end of section 46 in BMW shop manual for the K1200RS - I have not checked my CLYMER for equivalent info, but I know it is published in BMW shop manual.

I have NOT measured my original offset before removing the rear wheel spacer, but the fact the pull-to-the-right was reduced to almost nil was good enough for me. However the front tire cupping / wear on left has not fully disapeared - as discussed in earlier posts, there are other factors at work (heavy steering biased of K1200RS, front tire pressure , Telelever design, crown of the roads...)
 

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Thanks Jean......!

My 5.5" wheel can be mounted in any position without interference.Maybe the 5" is different?

I had the FD off the bike when I checked fitment without the spacer.Center wheel bolt on only and rotated FD against the wheel,no clearance issue anywhere.

Lots of thread left on this pair of Dunlop's Roadsmart.8,000 kms so far and most of that through Montana/North Dakota/Minnesota/Michigan so no twisties and flattened the center as expected.Starting to cup now that I can find curves in QC and have to step over the tire ridge when leaning.All expected but the previous pair "started and kept" in the western twisty roads wore out near perfectly.

At 8000 kms the Michelins/Metzelers were always done for.10-11,000 and maybe even better with the cheaper Dunlops I'll stick with them for a while.
 

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Thanks Jean......!

My 5.5" wheel can be mounted in any position without interference.Maybe the 5" is different?

I had the FD off the bike when I checked fitment without the spacer.Center wheel bolt on only and rotated FD against the wheel,no clearance issue anywhere.

Lots of thread left on this pair of Dunlop's Roadsmart.8,000 kms so far and most of that through Montana/North Dakota/Minnesota/Michigan so no twisties and flattened the center as expected.Starting to cup now that I can find curves in QC and have to step over the tire ridge when leaning.All expected but the previous pair "started and kept" in the western twisty roads wore out near perfectly.

At 8000 kms the Michelins/Metzelers were always done for.10-11,000 and maybe even better with the cheaper Dunlops I'll stick with them for a while.
Thanks for the note about the wider 5.5 inch rim being safe without the spacer - mine is the 5.00 inch rim of course. So... I have edited my post above to specify that this issue is related to the 5.00 inch rim.

Glad you like the Dunlop RoadSmart III as I also took advantage of their nice $$$ rebate last year. Mine has accumulated only 4,000 KM up to date, but overall most reviews I had read were positive - so is my experience until now. However I have not yet tried it in fairly heavy rain.

Got sick of the high price of the Michelin Pilot-Roads and the bad cupping on front (that came way too early to scrap a tire that still had some good tread). The other "good choice" are the Pirelli Angel-GT, but like Michelin PR these are getting expensive...

Please, let me know a bit before you get to my area during the current trip.
 

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Amazing. People spend a lot of money to get tire balancing tools to place those tire weights accurately. Not much on tire alignment and setting spacers. I will have to pay more attention to that next tire change.

Not typical of me to ride no-hands going down the highway but I sure would want the bike to ride straight.

I appreciate you mentioning the trait.
 
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