Is the rear pulley tight? If the rear drive pulley is not tight it will wobble during high speed spin and drop the belt. Only other cause I can think of for this would be the rear bearing starting to fail allowing the entire shaft to wobble. You would be aware of this courtesy of a very loud sound during spin though.
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Is the rear pulley tight? If the rear drive pulley is not tight it will wobble during high speed spin and drop the belt. Only other cause I can think of for this would be the rear bearing starting to fail allowing the entire shaft to wobble. You would be aware of this courtesy of a very loud sound during spin though.