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I've been reading several posts regarding the left pull issues and having come from an ST1300 know that bike had similar issues. The folks on the ST-Owners web site found a resolution, as I can testify, it worked for me.

So, my K1600GT had an ever so slight left pull. When I changed to the PR4's I decided to give this a try on my BMW.

Specifically, I loosened the pinch bolts, put full weight on the front end and rocked the bike, then re-tightened the right (right side from sitting on the bike looking forward) and then tightened the left side. This is reverse of what the article below states but my logic was that I had a left pull whereas he describes the right pull. So, I either remedied my issue or it was a fluke when I installed my new tires. I just glad I've got no pull.

I hope this is a simple resolution for us. Please let us know if you've tried it and it works.

Article ST1300 - Bike Pulls to the Right

NOTE: THE TORQUE SETTINGS ARE NOT FOR THE K1600.....THIS IS FROM THE ST-OWNERS WEB SITE.

(Note: Axle pinch bolts are finger loose at this point)

1. Tighten the left axle pinch bolts to 22 N-m (2.2 kgf-m, 16 lbf-ft)
Note: Indication of “Left” is if you were sitting on bike
2. Tighten Axle Bolt to 79 N-m (8.1 kgf-m, 58 lbf-ft)
3. Tighten the right axle pinch bolts to 22 N-m (2.2 kgf-m, 16 lbf-ft)
4. Now loosen the left axle pinch bolts
5. Note: During the assembly process, this is where you would be installing the brake calipers.
6. Set the bike down where the bike's weight is on the wheels. Lock the front brake and push the suspension up and down several times.
7. Tighten the left axle pinch bolts to 22 N-m (2.2 kgf-m, 16 lbf-ft)


You’ll notice that they have you loosen and retighten the left axle bolts before and after you’ve tightened the axle. I think this may be where the front end pulling is coming from. With the left axle pinch bolts tightened down, tightening the axle bolt would pull the two forks together……or more precisely, it’s pulling the left fork towards the right. Once you’ve tightened down the right axle pinch bolts, loosening the left axle pinch bolts lets the assembly center itself.

I hope I explained this in a way that makes sense.

So if your ST is pulling to the right, and it's definitely not tire related, give this a try. Loosen everything up and tighten it in this order. Make sure the front tire has no weight on it when you do it, too. Put the bike on the center stand and have someone push down on the bike while you work. If you've had your bike less than 30 days or are approaching the 600 mile service, take it back to the dealer. Tell them it's pulling, (don't say it happens when you take your hands off) and ask them to loosen and recheck the front wheel. Mention that the set-up manual is specific about how the front wheel is torqued and if not done correctly it will pull.

I also looked to see if there was anything with the back wheel that could cause it. The wheel just bolts on with no adjustment possible from what I can tell.

It’s interesting to note how the set-up directions for the previous year differed. For the 2007, they indicated that the axle bolt be torqued first, then the right side pinch bolts, the brake calipers would be installed and then the left side would be torqued.
 

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In my experience, the pull almost always goes away with new tires (PR3 and RS2 for me) and then progressively returns as the tires age.
 

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This should not work on the K16.

The ST13 has an axle with a bolt on one end that in theory could pull the forks together (assuming the other end of the axle is clamped in its fork leg).

That can't happen on the K16: the K16 axle cannot be inserted unless the right leg pinch bolt is loose. Once inserted, the axle threads into the bushing in the left leg (the left pinch bolt must be tight, or the bushing rotates and the axle can't be tightened). Because the axle is still loose in the right leg, it can't pull the legs together.
 

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Discussion Starter #4
That can't happen on the K16: the K16 axle cannot be inserted unless the right leg pinch bolt is loose. Once inserted, the axle threads into the bushing in the left leg (the left pinch bolt must be tight, or the bushing rotates and the axle can't be tightened). Because the axle is still loose in the right leg, it can't pull the legs together.
After the axle is installed and all is tight, loosen the pinch bolts to take the load off of the forks and then put the weight of the bike on it, lift it back up and tighten the pinch bolts.

The axle should've already been tightened/torqued to spec before loosening the pinch bolts.

I theory, any twisting load put on the forks by torquing the axle should now be relieved.

If you have the pull, what do you have to lose to try it? If it fixes your pull, I (or we here) would like to hear about it and likewise, if it doesn't fix your pull I'd still like to hear your response.
 

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I theory, any twisting load put on the forks by torquing the axle should now be relieved.
That is exactly the point: with the K16's arrangement, you can't have a twisting load -- the right pinch bolt can't be tightened until the axle has already been fully torqued, and before you torque the right pinch bolt, there's no torque being applied to the axle at the left leg (since you've stopped tightening the axle).

If you have the pull, what do you have to lose to try it?
Time I could be spending trying to figure out a rational explanation that fits the K16's actual configuration.

If it fixes your pull, I (or we here) would like to hear about it and likewise, if it doesn't fix your pull I'd still like to hear your response.
Don't get me wrong, I'm a charter member of the left-pull club (there are some threads from the early days of this list that show the extent to which I was willing to go to fix it). I more than most would love to find a solution. Just trying to save folks time trying to transfer a technique from a different bike with a fundamentally different axle arrangement to the K16.

At best the ST1300 approach would result in the entire axle/bushing/wheel combination being shifted to the right as the left bushing slips sideways out of the left leg -- that is exactly the result of my Duolever shimming project (i.e., shifting the wheel to the right relative to the bike's centerline, which cured the pull, but left the handlebars turned off-center).

Sorry, but there is nothing in the K16 axle arrangement which would alter the "tilt" of the tire, the issue fixed by releasing the pinched-together ST13 fork legs.
 

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In my experience, the pull almost always goes away with new tires (PR3 and RS2 for me) and then progressively returns as the tires age.
Mine has been the same 100% of the time and I'm on my third set of tires - made no difference. I have thought of loosening the pinch bolts and rocking it, but have not tried it yet. Might just for grins.
 

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I have found the easy answer. if I move my backside a little to the right my bike no longer pulls to the left
 

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I'm able to consistently remedy my left pull by putting 6l of water in the right bag (pretty sure that's over the weight limit). It's amazing what a difference it makes for reducing the effort to turn right.
 

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Just a thought, and possibly this has been brought up in the past, so I prefer not to be berated for it, but, my belief that these bikes seem to want to wonder, pull, tilt to the left is the rotational reaction from the spinning of the drive shaft, if looking longitudinally from behind the bike my guess would be that the shaft spins anti-clockwise thus wanting to drag the bike to the left. Again, please don't pile poo on me, just a thought. I think BMW believe they fixed this with the additional flex point in the swing arm, but perhaps the drive shaft of the K16 is more substantial due to the horsepower and torque of the beast and still creates a reaction. Happy to be wrong, just a thought/suggestion. Baz.
 

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The other forces you have to consider are the two giant gyroscopes called wheels which would naturally counter the action of the driveshaft and the distribution of their weight away from the center of mass would allow the wheels to have a far greater influence on balance than the driveshaft would which is closer to the center of mass. Its not the driveshaft.
 

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I hear ya, all I can say is that all my drive-shaft bikes have had a similar feel, K1, K75, K16, R1100s, R12GS, if I want to take my hands off the bars I know I have to transfer a bit of weight to the right side of the seat. Normal riding with hands on the bars it's not noticeable. I have never noticed it on any of my chain driven bikes. I certainly would not dispute what you say, just my observations.
 

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is the rotational reaction from the spinning of the drive shaft, if looking longitudinally from behind the bike my guess would be that the shaft spins anti-clockwise thus wanting to drag the bike to the left.
Over the prior 28 years I have owned a '75 GL 1000, a '76 GL1000, a '92 K75s, a '95 K1100LT, A '12 GTL, and an '18 GTL. Of the six shaft driven bikes with ~500,000 miles between them, the only bikes that pull left are the GTLs.
 

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I hear ya, all I can say is that all my drive-shaft bikes have had a similar feel, K1, K75, K16, R1100s, R12GS, if I want to take my hands off the bars I know I have to transfer a bit of weight to the right side of the seat. Normal riding with hands on the bars it's not noticeable. I have never noticed it on any of my chain driven bikes. I certainly would not dispute what you say, just my observations.
Some of those bikes had driveshafts on the opposite sides, and that dictates that the shafts would have rotated in opposite directions?
 

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All I know is I went for over a mile hands-free yesterday. And I had stuff in my left bag with the right bag empty. I could get it to pull left consistently if I shifted my butt left. I could get it to shift right consistently if I shifted my butt right. It took what felt like a slight right of center position of the butt to keep it neutral.
 

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I'm a former ST1300 guy. This procedure cured my severe left lean on the 1600, now very neutral, it stays going where you point it. Much nicer to ride now and the new tires have over 2k on them with no change. BTW I do this to all bikes. Besides it's easy and free so what do you have to lose by trying it if your bike leans and you're changing tires?
 

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The idea of this being a result of the driveshaft has been suggested before. And while there certainly is torque on the shaft, it occurs in equal amplitudes and opposite directions at each end.
Imagine you're sitting in a small boat on the water. This boat has a solid vertical shaft attached to the floor with a wheel on the top allowing you to put a twisting force on it. No matter how hard you twist, the boat will be unaffected.
My 1600 tracks straight, but the left pull has been reported enough times to be considered a legitimate concern. I think, however, it is a geometry problem, not one of physics.
 
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