Reply To: Have I broken my new Bobber? Great British Handcrafted Motorcycles › Forums › CCM Motorcycles – General Discussion › Have I broken my new Bobber? › Reply To: Have I broken my new Bobber? 5 June, 2022 at 12:21 pm #12079 martin G10Member Hi, The circumference numbers came from Phil Collier After Sales Manager CCM. CCM setup uses 2200 for the Six and 2020 for the Bobber, P1 = one magnet per revolution of the wheel. martin