chicago bmw has the belt for 227$
If the time has come to change your belt:
The basic steps involve:
1: loose the eccentric clamp
2: remove fastener for sping strut (so that we can insert the belt)
3: remove belt cover
4: unclip ABS sensor
5: strap rear wheel to rear frame
6: strap swinging arm
7: mount the belt and reverse order
According to Daily:
Belt changed at 90,000 miles and again at 131,000 miles. I wouldn't consider it an easy job, but if you have a good tool selection, it isn't all that bad.
I think the hardest part, was gettin' those lousy little bolts that hold the rear brake caliper to the swingarm out. I finally took a 1/4" drive, 6mm socket, cut 1/2" off of a 6mm allen wrench and used it in the 6mm socket to get to them, with a 6" long 1/4" drive extension. The problem is, there just isn't enough room to get a standard 3/8 drive allen in there.
The rest of it is pretty simple, just use common sense. Do not try to take the belt guard off, just take out the bolts that hold it to the swingarm and leave everything hang there. I didn't take the wheel off the first time, that was a mistake, the job is much easier with the wheel off. You have to support the brake caliper and the swingarm from the rear frame section. I just took a couple of straps and went all the way around the frame where the seat perches.
You have to disconnect the shock linkage at the swingarm and remove the swingarm pivot bolt altogether, watch for any spacers when you pull that long bolt out. After you get the swingarm pivot bolt out, you can pull the swingarm back and you'll have enough space to slip the belt between the frame and the swingarm. CAREFULLY!!!! You don't want to twist or kink that high dollar belt!! Just be very careful and watch what you're doing, make good use of the "what if" scenario before you do anything.
As far as belt tension goes, the preliminary adjustment is to tighten it enough so that you cannot push the belt down far enough to touch the swingarm on top, at center span, with a reasonable amount of force. Take it out for a ride, when you get back, just get off the bike, leave it on the sidestand, DO NOT ROLL IT UNLADEN AT ALL and see where the belt is riding on the rear sprocket. If the belt is somewhere between 0 and 2mm from the inside sprocket flange, the tension is good. If the belt is running 3mm or more from the inside flange of the rear sprocket, it's too loose. Tighten the adjustment 1/2 turn at a time and test it each time, until you have the proper belt position on the rear sprocket.
Finally, when you have the proper belt tension, do a final check on the torque on the eccentric pinch bolts and the adjuster bolt, torque the 2 pinch bolts to 16 ft.lbs. first and lastly, torque the adjuster bolt the same. Recheck all three of them in about 200 miles, if they take any torque then, recheck them again in another 200 miles until there is no change.