This rgs came to me in bits, the guy that had it before had completely stripped it with the intention to re-build it, he must have got as far as renewing all the bushes in the crank case and the inner timing case and then went and died, 35 years later it came to me. On assembling the inner timing case would not fit flush with the crank case, I found that the idler gear was hitting the shoulder on the inner timing case bush. After making sure all was in line, I came to the conclusion that the shoulder of the bush was to thick and it was a faulty part so I reduced the shoulder by half and it fitted OK. I had been running the bike for about a year (about a 1000 miles) no problem except the oil was getting into the the dynamo chamber and out the back of the dynamo. Now as the weather was turning I decided to strip it down and get to the bottom of it, (so to you guys at the forum I go) found that the wrong bush had been fitted and instead of channelling the oil away from the dynamo housing it was pushing it through. I rang Brian at lighting spares and he told me that the part no. in the BSA parts list was wrong, he sent me the right parts ( got them the next day) went to fit it yes! same problem and I had to reduce the shoulder on this one to get the case to fit flush.
The bike is going great and no more oil leak but this con-not be right.
Steve