I've noticed that my drive belt sits right on the outer edge of the rear pulley. It never moves over the edge and the full width of the rubber teeth are engaged but it looks a bit odd to me. I never noticed this on my previous GT or ST. Does anyone else have the same? I'm just not sure whether it's something I need to be worried about. The bike has around 2000 miles on the clock and is still under warranty. So I could run it into the dealership if it looks as though I have a problem.
Just had a look at mine and it is sitting centrally on the sprocket. It looks like yours has moved slightly outwards, looking at the marks on your pulley. What is the tension like?
My 2013 F800GT belt normally runs towards the inside of the pulley. Not super tight against the inside lip/stop, but just naturally tracks in that direction. With so few miles, it seems unlikely anything is worn, but might be worth checking your hub clamp bolts, axle bolt and belt tension. Put it on the center stand, grab the wheel and manually try wobble the tire back and forth, should be tight and no clunks or deflection. Luckily it's under warranty so if anything seems questionable ask the experts.
Thanks for the replies. My previous GT and ST belts used to run towards the inside of the pulley as well, which makes me wonder if anything is amiss. I'll try wobbling the back wheel to check for play in the hub. The belt tension seems ok. If I can't find anything I may just run it into the dealership. They are reasonably close by.
Rich,
In my 14 years ownership of an ST and two GT's the belt runs fairly close to the inner flange of rear pulley.
However, I have noticed on all the bikes, if I push the bike backwards a fair distance [up driveway and into garage], the belt drifts away from the flange. Recovers when forward motion returns.
I would be inclined to have a ride to dealership.
Thanks Chris, that's really interesting. I have noticed that when I arrive at my destination the belt is central on the pulley. It moves to the edge after I have pushed the bike backward into the garage. It's around a 6 meter distance to push it backward into the garage.
I would definitely have the dealer look at it.
With the bike still under warranty do not do any wrenching on it.
They do not “all do that”, so don’t let the dealer tell you that.
Good luck
It's good you asked this question. It shows you pay attention to how your bike looks and feels. In fact, you compelled me to check my '18 GT's belt, and turns out it's centered, so it's good. But if you ever have doubts, for sure ask the question and take it to the dealer if there's any doubt.
Never accept, as the previous poster said, "they all do that".
Ok, so I went out to the bike and rotated the rear wheel 360 degrees in the forward direction of rotation. Belt is now back running in the centre of the pulley, which suggests that it runs centrally when travelling along. Seems it migrates to the outer edge if the bike is moved backward. I don't recall seeing this on my previous GT or ST but Chris F seems to have had a similar experience. Wondering if anyone else experiences this belt moving on the rear pulley. I will probably drift by my local dealer in a couple of weeks anyway just to check.
Worth checking the front drive sprocket is correctly torqued. I noticed the belt on my ST had migrated to near the outer edge of the rear sprocket and thought nothing of it. Couple of days later the front sprocket emerged after cutting through the plastic cover, bounced of my right boot and took off down the highway. Bike was low kms and belt original so pretty sure the sprocket had never been touched.
I think the OP was referring to the smaller front drive pulley on the gearbox rather than the large pulley on the rear wheel. If that's the case then it looks as though both pulleys can suffer issues. Very worrying.
It would be interesting to find out which sprocket flew off. I thought the front sprocket on the ST was better protected against hitting the rider's boot.
Hello there !
Has anyone posted an actual solution or the cause of the problem?
I have a 2009 F800ST with less than 15,000 Miles on it. I have recently noticed that the drive belt is tracking way to the right, just barely past the teeth (just as described in this thread) on the rear pulley but not any farther. However, when I turn the rear wheel while on the center stand the belt goes back all the way to the left next to the flange where it should be (I listened carefully and didn't hear any wheel bearing noises or saw any wobling either).
But when I bring it down from the center stand and I roll it in the garage it tracks slowly to the right again...ughh.... I have ridden it for at least 40 miles like that, and I don’t feel or hear anything, but I want to fix it. I did look at the front pulley bolt torque and it all looks normal.
Is it possible that at a recent service the belt was tightened too much and is causing the belt to track to the right (I remember the belt to be pretty loose even when new)?
or is it possible when the belt was adjusted that one of the two "adjuster clamp screws" was not tightened correctly?
I was thinking about loosening the belt and starting over.
Thoughts?
Hello there !
Has anyone posted an actual solution or the cause of the problem?
I have a 2009 F800ST with less than 15,000 Miles on it. I have recently noticed that the drive belt is tracking way to the right, just barely past the teeth (just as described in this thread) on the rear pulley but not any farther. However, when I turn the rear wheel while on the center stand the belt goes back all the way to the left next to the flange where it should be (I listened carefully and didn't hear any wheel bearing noises or saw any wobling either).
But when I bring it down from the center stand and I roll it in the garage it tracks slowly to the right again...ughh.... I have ridden it for at least 40 miles like that, and I don't feel or hear anything, but I want to fix it. I did look at the front pulley bolt torque and it all looks normal.
Is it possible that at a recent service the belt was tightened too much and is causing the belt to track to the right (I remember the belt to be pretty loose even when new)?
or is it possible when the belt was adjusted that one of the two "adjuster clamp screws" was not tightened correctly?
I was thinking about loosening the belt and starting over.
Thoughts?
I changed the rear tire of my Zero yesterday and noticed that its drive belt is rubbing against the cogwheel's flange. The specifications for the belt call for a 1mm gap between the flange and the edge of the belt. That means that I will need to adjust the tensioning bolts (which are just like any other motorcycle with a double-sided swing arm and a chain) to move the belt on the sprocket. By adjusting one side or the other of the adjustment bolts, you can move the belt to once side or the other on the cogwheel. Does the ST have any sort of similar adjustment that will angle the wheel slightly one way or the other to move the location of the belt on the drive sprocket?
Could the belt on the drive sprocket be offset a little? Maybe all you need to do is to push it back toward the engine to cause the location of the belt on the driven sprocket to move over too.
Thanks to everyone for your kind responses. What is interesting is that while up on the center stand as I turn the wheel by hand the belt tracks perfectly on the left side like it always has.
Check the front drive sprocket and see where the belt rides while the rear is at the outside of the wheel sprocket as shown on post #1.
If it is at the outside lip, then you should be OK. The belt is running at its limits. No two bikes are the same on this subject (too many variables).
If it is at the inside lip, there may be an issue with the belt itself. Suggest removing the belt and turning it around and re-installing (per procedures).
I had the same experience on my F800S. Belt not riding where it should, often found the belt even after only going forwards somewhere off the limit on the inner side of the pulley. So I took the rear end apart and lo and behold: the bearings themselves were fine, but the ring that the bearing next to the pulley is supposed to run on had ruined the rear axle. You won't hear any problems with the bearing and it will spin just fine if you're not putting any weight on it, but that doesn't mean that the axle isn't toast.
Take the rear pulley off ( its locked with 150 Nm and loctite, so your breaker bar should be the "I'm not asking"-type - 150 Nm is 15kg of force with 1m of leverage) and try to pry the ring out that the shaft seal that you'll see there seals against. If that's moving ( mine fell right out after I took it out of the rear swing arm), your rear axle is considered toast by BMW and the entire eccentric along with it.
They'll sell you a third gen rear axle as a replacement. For a considerable sum of money.
This is what mine looked like after I got the eccentric off:
the brown stuff was powdered rust formed out of shavings. the rough surface tight below the splines is where the bearing surface for the roller bearing is supposed to be pressed on. Needless to say, there isn't a lot of pressure going on there.
Side note: Why does this forum mention jpeg as an allowed format, but then only lets me upload pngs?
Regarding your jpeg/pngs (whatever those are) you will need to post your question in the Forum Help/Support section. The Form Administrator, HalfPint, should be able to answer your question. (Eventually)
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