After 15,000km on my bike I noticed a pulsing action in the back wheel when braking. At first I thought I had some grease on the rim but it didn’t go away. Turns out there was a long crack all along the rim where the brake pads have worn away the metal. Keep in mind that these little wheels rotate twice as often per kilometre so that’s as though I’ve 30,000km. (Not buying it?)
I ordered a whole new rear wheel with the idea of using the old Sturmey-Archer hub to experiment and learn how to maintain it (without leaving me stranded if things go badly).
I finally got around to putting on the new wheel along with new tires, chain, sprockets, brake pad and went back to a 50-tooth chainring. I had installed a 42 for the hills on the Cabot Trail. It was like riding a brand new bike – so many noises eliminated. Now I’m ready for the trip to Windsor. More to come.
Cracked rim 
Brand new bike!