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« on: August 19, 2020, 12:08:09 AM »
While it is the case that belt and pulley and drive sprocket wear together as an assembly, the bike has just over 3200 miles on it and the kind of wear we are talking about may be very small. This is still something to consider, and thank you.
In the matter of the wheel adjusters, they will not necessarily be even, on a Zero. The belt tracking procedure in the manual describes a deliberate difference between the left and right side adjusters, in order for the belt tracking to be shifted to the right or left as needed, much the same as the deliberate tilting of the upper bandsaw wheel to control the tracking of a bandsaw blade. Therefore, the rear wheel IS deliberately angled ever so slightly off of a right angle to its axis of rotation to achieve correct belt tracking on the pulley. (This is different from the wheel adjusters on the Milwaukee ICE bike I had. Accurate landmarks on both sides of that bike were provided to insure accurately matched adjusters. That belt was maybe 4 times as wide as the Zero belt, and the wheel pulley was flanged on both edges to keep the belt in place.)
In the matter of rear wheel runout, I made my observations at the wheel rim, where it meets the tire, and I believe the wheel runs true. As I said, I set up a heavy stand near the wheel pulley, to monitor the wobble of the pulley, and marked the pulley with chalk. There are 4 bolts holding the pulley to the wheel. The chalk mark was symmetrically opposite two adjacent bolts. Loosening the bolts opposite to these bolts and springing the pulley slightly, the pulley seemed to run true, visually. Radically improved over the previous condition. I made a pair of thin shim washers and put them in place and re-fastened the two bolts and ran the wheel again. I was satisfied with the run of the pulley, and proceeded to re-track the belt, per the manual instructions.
On tightening the axle bolt and running the wheel at about 10 mph (indicated) I hear the clicking sound, rising and falling in frequency as the wheel increases or decreases in speed. If it is the belt finding its new shape, I can live with that. I just need to know that I am not murdering a bearing in the wheel.
I intend to re-do the belt tracking adjustment again, to see what happens. I come from a heavy industry background, in which shimming a pulley is an acceptable fix to improve alignment, so I am comfortable with 2 shim washers on a 4 bolt pulley. My concern is the new noise. Thanks.