Random fast changing power readings on BBS02


New Member
United Kingdom
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 1 shows a smooth power level anywhere between around 150 and 200 Watts as demanded. Also, the P (walk) assistance is meant to be limited to around 4mph. Randomly this will not be the case and the bike will surge at quite a high power level when the P function is activated. I have tried disconnecting the throttle and the gear change sensor. Neither affect this problem.

Has anyone else experienced this problem? Is it a known problem and is there a cure?