The non-ABS Rockster has an odd system for driving the speedo. The magnetic pick up is mounted into the rear hub case, and is driven by a steel ring, pressed onto the (I assume aluminium alloy) hub.
Problem though is that if this ring is for any reason removed, it needs to be pressed back on properly, which didn't happen when the rear hub bearings were replaced. (the person doing that job wasn't aware of the steel ring, and had no experience of it). The ring "can" be pushed back onto the hub through the speedo drive hole (I've done this in the past). Problem is when the hub is particularly cold, the ring won't stay on using this simpler method.
So - I, or someone, needs to strip the hub again to press this steel ring on properly, so - what's needed?