I have an 66 cc motor on my bike , I geak 3 or 4 spokes everytime I ride. I know you don't let the clutch out when you are going fast. I think my spokes are about 15 gauge, and yes they are at the right tension
I had a broken spoke problem on my old Schwinn Racer with its 3-speed hub long before I motorized it. Spokes broke on the rear wheel no matter what I used, including stainless steel. It turns out that long wear had made the spoke holes in the hub into ovals, which for some reason will break the spokes, though I still don't know just why. I could have and probably should have bought a new hub, but instead I used my oxy-acetylene torch to fill up the holes with brazing--kind of a brass welding rod--and then re-drilling the holes. The spokes never broke again.
Strangely enough I have a 1970 Schwinn racer with that same Sturmey Archer rear hub...but its been fine. The hub on my gas bike is a coaster brake hub, and the hub holes are nice and round. I'm at a dilemma, this bike is a board track facimily and I don't want shiny spokes like stainless...I'm wanting it to look like it had been in a barn for 90 years. I may have to go t larger gauge stainless spokes and weather them with paintI had a broken spoke problem on my old Schwinn Racer with its 3-speed hub long before I motorized it. Spokes broke on the rear wheel no matter what I used, including stainless steel. It turns out that long wear had made the spoke holes in the hub into ovals, which for some reason will break the spokes, though I still don't know just why. I could have and probably should have bought a new hub, but instead I used my oxy-acetylene torch to fill up the holes with brazing--kind of a brass welding rod--and then re-drilling the holes. The spokes never broke again.