My reg/rec went dodgy (nearly 17v at the battery) recently so I’ve replaced it with a new one. Both are RR51 types and I’ve literally just swapped the wires over like for like (2 x yellow ones to the alternator, white one that goes back to the fusebox somewhere, red to batt +ve, grey to batt -ve). The battery is a little undercharged at 11.75v but the bike started. At idle, it stays at 11.75v and the battery light is on, above idle it goes up to 11.77v and the battery light goes out, but clearly it’s not effectively charging. Where should I check next? edit: never mind, I found it. A connector crimped by a previous owner was dodgy, unplugging it and plugging it back in obviously disturbed it. Crimped and soldered a new one and it’s working now.
