random power

I have a Bosch Smart System Performance Line Speed. It has less than 30 hours on it total. The bike will randomly cut in and out randomly. I have had it to the bike shop and the error reads that I disconnected the battery completely or that it has lost contact with the battery. The shop has...

I have a BBS02B (36V, 350 Watt) kit with an 850c display fitted to my Cannondale Trail 2 29er. I have it set up for three assistance levels (50% level 1, 75% level 2 and 100% level 3). When riding, the power meter rapidly changes between any value between 0 and around 600 Watts. Normally, level...