When I was out yesterday, the chain got caught between the gears and the wheel - this was with bike.3. I had to turn the bike upside down to get it sorted out. So today I adjusted the gear's travel, so this shouldn't happen in future.
I also had a look at the disc brake. A disk brake is supposed to be more effective than a rim brake, but I'm not finding that. I had a look at it in case the problem was worn pads, but I don't think it's that.
I just won an Ebay auction for a doglegged rear carrier plus two panniers, for £31 (including P&P). When that arrives, I'll try to fit it to bike.3. And my P-clips are on the way; they should make it possible for me to attach the rack to the bike, even though it doesn't have the standard fittings.
I've also been doing a lot of preventative server maintenance. Before a drive fails, it tells you, in various ways, that this is going to happen. I've replaced six drives for this reason.
Tomorrow I'm going back to Stamford - it's a rich hunting ground!