I was riding home recently when the motor started making a grinding noise. I got it home and took the cover off and saw that a C-clip on the right-hand side had broken up into a half-dozen little pieces which were now all stuck to the motor magnets.
I cleaned out the broken bits, bought a box of C-clips and installed a new one. I put the side cover back on and noticed that it didn’t sit flush against the side of the motor, there was a tiny gap. Apparently the bearing in the side cover had been pressing against the C-clip and that was probably what caused it to fail. Looking at the wear on the axle it’s clear that the bearing was riding a bit too far inboard, too close to the C-clip.
I emailed Oxygen about the problem and they offered to repair the motor under warranty, but it would mean shipping it back to the UK. I looked into shipping costs and decided it wasn’t worth it. The motor still works fine, if there was a bigger problem then I would have paid for shipping and taken their offer to repair it. It would be great if Oxygen established a US distributor, but they were totally helpful through this whole process and I still give them high marks for customer service.
I was worried that the side cover pressing on the new C-clip would cause it to fail eventually too. The big aluminum piece in the picture above is pressed solidly onto the axle and doesn’t move, and even if it did try to move the side bearing would hold it in place. So I figured that the C-clip really wasn’t doing anything and decided to just remove it. I’ve put about 150 miles on the motor without the C-clip and it’s been fine.
For reference, my kit is the 2012 version. For 2013 Oxygen switched to a different motor, so hopefully this problem shouldn’t affect any of the newer ones.
I also managed to badly crack my LCD unit when the bike fell over while I (stupidly) had it balancing without the front wheel. Oxygen has also switched to a new LCD unit for 2013, so I got a bit of an upgrade with my replacement unit. The new one is better than the old one on several counts. It adds an assist level zero, so it can still power the speedo/odo even if I don’t need e-juice. The whole unit is a bit smaller, which is nice, and it incorporates the buttons into the same unit, which clears up some extra handlebar space. I’ll add some pictures of it later…
Original review, March 2013.