Originally Posted by
nesteel
Where are you finding the info that Klein spec'ed a Superbe Pro double crank? When I bought that bike, it had 6207 EX cranks, RD, and brakes. I would assume it used a Superbe FD because the Shimano units couldn't be adapted to the larger tube, or the through tube mounting.
But yes, finding a triple crankset that sits on a narrow BB spindle can be a pain. Not a situation that is very "vintage" friendly.
I couldn't find the OEM spec'd group, so I started with what I had: a Superbe Pro bolt-on FD that I'd not seen from any other brand, a symmetrical BB, and the shifter mount intended for a certain model of Suntour friction shifters. I tried 3 other sets of Suntour shifters that would not work on those mounts. After mounting a Superbe Pro crankset and looking at the chain line, which was consistent with the "tucked in" FD and testing the range with the L Suntour friction shifter, I assumed Superbe Pro was intended. It didn't make sense to have 52/42 and a short cage RD on a frame with double rear eyelets and front eyelets, but then, after mounting a Superbe Pro RD and getting a very smooth drive train, I assumed Superbe Pro was what they had in mind. It seemed very much like this setup was intended. Other cranksets sat too far out for the FD and the L shifter, I knew of no other bolt-on FD for this frame, and the odds, to me, of another group fitting up and working this well were too high to not consider Superbe Pro as the OEM group.
It did seem odd that a frame designed with double rear eyelets and single front, with plenty of clearance, would be spec'd for a more racing set of gears. It also seemed odd that Klein would spec a mix of Suntour and Shimano components. Everything about this frame said "special" and "proprietary" to me as I was trying to build it.
I simply don't have the legs to do semi-loaded touring with a 52/42 and a short range rear cassette, but once I
assumed that setup was intended, it was simpler to search for components that would fit
into that setup and still meet the capabilities I needed.
I adapted a hybrid Trek's triple 10-sp FD, identical to the DA 7700 triple but intended for a maximum 50T chain ring. It had to be shimmed to meet the tubing diameter, and the range adjusted from a hair away from the ST in the "inner" position, and nearly 100% "out" in the outer position.
I used, as outlined before, the only crankset I knew that was a compact triple
and used a symmetrical BB. I'd remembered the RSX 3x7 compact triple group from a Diamondback Master TG I bought from a dealer, specifically to swap over to a Lemans RS touring build.
I adapted indexed shifters to work where none were intended, and even with the adaptation and the close-in FD/crankset, the range of the L shifter is used nearly completely up in hitting all 3 front chain rings. (Were the crankset to sit farther out, it would simply not work).
I'm not criticizing Klein, I'm just pointing out the challenges of imagining/guessing what was going on in 1984, and trying to make the vision created then into something workable for a compact triple touring bike with modern components in 2017. I also had a budget. I've since pulled the Tange steel front fork for a carbon Kestrel EMS Pro, which limits the front tire to 700x25, but makes it much easier to mount modern mid-range calipers. I'd love to find a 1" threaded carbon fork that accommodates a 700x28 tire, or even a 1" threadless carbon fork that accommodates a 700x28 tire. Of course, then I'd have to change the stem, and the bars, etc.... Until then, I'm going with what I have.
I didn't consider that writing about it would raise certain types of questions, but that seems to be more in the communication sphere than anything. I certainly wish this bunch would have been present in my garage when I showed them the frame and then said "I want to do ... with this bike." Probably would have saved myself a ton of time. At no point during the project did I consider giving up, which I've done with others (French). I just put it aside and waited for a different day. That's how nice that frame is.