Eric, they are Riv recommended Kool Stop E-bike brake pads (73mm, but they come in 54mm too). Excellent pads! All part of my ongoing schemes and attempts to simulate the power of v-brakes on my side pull r559 brakes. I’m ready to have someone weld on some v-brake posts for that strong-enough-to-slow-this-heavy-guy-on-a-bike v-brake goodness. But these are as good as it gets in the meantime, and they’re very good pads. I also use compression less brake cable housing, also helps at the margins.
“A guy who builds up tons of bikes asked me if I’d ever tried Kool-Stop e-bike brake pads, and of course not. Who’s going to do that out of the blue? I don’t replace brake pads until I hear the metal holders touching the rim, anyway.
The guy, Chris C., is not a raver and wasn’t pushy, but he seemed bursting with sincere enthusiasm for these pads, which he said are smooth and quiet and stop fantastically well, so we got samples, and holy cow.
I think these are as good as brake pads get, and I suspect they’re really the best in the world. The 73mm V-brake pads are thicker than most V-brake pads—probably so you don’t blow through skinny ones on rim-braked eBikes—and that’s another bonus. You can use the V-brake pads-with-holders on sidepulls, too.”