Not as exciting as Part 1, but...
I said it couldn't be done, but I was wrong. Casey managed to get a Porteur chain case to work with a rear derailleur and a 9-speed cassette. The clearances are tight, but it works perfectly. (Of course it won't work with a front derailleur.) The crank is a Grand Cru 110bcd fluted double, but with only one ring. A fair number of the original porteur bikes had 1X5 drive trains, so this modernized 1X9 is in keeping with tradition.
Speaking of single cranks, do you think we should get a single speed version of the 110bcd Grand Cru? It has more clearance that the 50.4bcd so is much easier to set up. And if so, what is the ideal chain ring size? I'm thinking 46t.
Some folks feel that the logo on the Grand Cru chainguard, in the previous post, is too big. Let me explain why I did it that way, even though I generally dislike oversize logos. The large logo on this chainguard follows a certain style of chainguard that I happen to love. Many companies made guards with their logos as part of the design. It was considered cool, even fashionable. My all time favorite is the CLB guard.
If you don't like this style then don't buy it; we already have plans to make another, minimal-logo, chainguard next year. The etching is super easy to change and we may change it every year. How about the circle containing a French rooster, sunflower, peace sign, yin and yang... Wonder if we should open up the design process and ask for submission from artistic customers? I've even considered making some blank ones that frame builders could have engraved with their own logos. But the Grand Cru design is what I wanted for my bike so that production run gets made first ;<)