Step one of my drivetrain overhaul is complete. My bike has a new sealed cartridge bottom bracket, which will be much easier to maintain going forward, particularly as we enter winter.
The new bottom bracket required new cranks, something I wasn't thrilled about, but it all works flawlessly now. Perhaps someday I will find prettier cranks with the correct taper.
It's worth noting that, while we could have installed the cartridge ourselves, removing the old cups from the old-fashioned bottom bracket was not something we could do ourselves. Shops have expensive specialized tools to complete the task quickly and efficiently. My second-favorite mechanic on earth (I'm not married to you, J) did all of this for less money than the one-month bus pass I would have had to buy while we fought with the bike. In other words, money well spent.
As part of the repair we brought in the hack-sawed SKS chainguard bracket which he put on when installing the cartridge. It was originally 3-armed and we removed one to leave just two mounting points for the chainguard. This modification allowed me to install my pretty French chainguard!
It would probably look better with a larger chainring but this is the size calculated to be ideal for Step Two of the drivetrain overhaul, internal 3-speed hub. My husband finished the wheel last night, so that's happening soon. You can see that the modern cranks are a little, uh, robust, beefy, for the vintage bike, but they do work well.
I had to drill a new hole in the chainguard to match the bracket. It was easy to do. The bracket is threaded, so I haven't added the nuts to the screws yet. I will do that this weekend as I now have it positioned just right.
Here you can see how the chopped SKS chainguard mount holds the chainguard without touching my frame. It's clamped on by the bottom bracket. I like that there will be no cause for more rust than I already have...
SKS, I know you're not reading but if you were I think this would be a natural product to offer. So many people struggle with mounting a custom chainguard, why don't you offer a vintage chainguard kit?
I've been riding with it for a week now and it's been great. I feel like my bike has new jewelry, and my trousers have been protected. The new bottom bracket is a more subtle upgrade, but it does make the bike feel stronger, smoother, and thus safer. I'm a very happy cyclist.