I wanted to provide an update on the reliability of the Derby Cycle Impulse II motor system. I own a bike shop in Boulder, CO and used to focus exclusively on electric bikes. I've sold thousands of electric bikes and serviced many of the bikes on the market current and past. I'm a Mechanical Engineer by training, have worked in Silicon Valley as an Electrical Engineer, and a certified machinist so I have quite a bit of background with motors from both a mechanical and electrical standpoint. I have a few customers that purchased the Focus Thron Speed 27.5 bikes equipped with the Impulse II motor system. One of those customers recently experienced a loud noise which he thought was coming from the motor. Upon inspection I could tell immediately that it was a bearing. Since Focus USA decided not to warranty the problem, I decided to open the motor and fix it myself. What I found was interesting. Bearing failure was indeed the issues but I found that the bearings used on the part of the motor that failed were, in my opinion, severely undersized. Most of the e-bikes that I have sold have been equipped with the Panasonic mid-drive. I have customers that put 8-10 thousand miles a year on those bikes and they never fail. Personally I ride a bike with a Panasonic motor and I have just over 39,000 miles on the bike (not a misprint). The offending bearing on the Impulse motor is located on the gear reduction shaft, which holds the large plastic/nylon gear with the one way bearing. I am posting a picture of the bearing sitting next to the same bearing from the Panasonic motor. As you will see, the Panasonic is MUCH bigger. This customer with the Focus Thron has just over 2500 miles on the bike. In my opinion, that is still low mileage. For a bearing to fail after so few miles is shocking.