dddd
Joined: 11 Jan 2004
Posts: 3345
Location: NorCal10/15/17 10:31 AM |
Yeah, it sounds like this Crescent used the Swiss threading, which even Peugeot adopted around 1980 before finally changing to BSA (English).
You're right about 700c being the standard for racing tubulars and with 27" being the standard for touring clinchers, but there were 700c touring clinchers used in France since at least the 50's and probably earlier. A bigger company would differentiate their products though depending on what market that each batch of bikes was to be sold in.
27" wheel production road bikes made it into at least the early 90's, though only on very low-end "ten-speed" road bikes and almost always with Shraeder valves as were appropriate to their wider rims.
Narrow (20mm) 700c clinchers (used on then-new, narrow, hooked-bead, double-walled rims) appeared in the mid-70's, and had become fairly popular in a range of widths (roughly 20-28mm) by 1980, and there were 27" counterparts to these same style and width tires and rims.
I really liked the fine Mitsuboshi "28mm"/27x1-1/8" onion-skin (really 25mm wide) clinchers as mounted to wider rims on my 1979 Fuji S12-S, a sensible and sporty tire/wheel sizing that is today once more widely in vogue.
My Steyr Clubman is a strange combination of standards, with it's "Precision Steel" frame having Metric tubing diameters, English BB threading and uniquely-Austrian 26mm-threaded steer tube with a smaller French 22mm ID. I had to source a replacement headset from an online Puch Moped supply shop in San Francisco, and the seatpost size was a very odd 25.6mm, but Kalloy/Amazon came to the rescue with a nice, long zero-offset post for it for $20 shipped.
Note that many front derailers will need to have their clamping plate mating surfaces shaved down a bit to clamp down tightly onto the smaller 28mm metric tubing, which typically measures well over that figure with paint thickness factored in. Metric brake cable housing clamps and shift lever clamps are also available and useful, the Metric top tube is actually slightly larger than English btw.
The 26.4mm seat tube ID could be either Metric or English, depending on the tubing spec. My (English) Raleigh Super Course with Reynolds "3 main tubes" measures 26.4mm ID, and better French frames built with Reynolds DB most often also measure 26.4mm.
The long and low geometry favors a shorter-legged, taller and fitter rider at first glance, but/and
if the HT and ST angles are slack:
1) the steering response will favor the use of a shorter stem and 2) the top tube will give shorter effective reach than indicated by it's linear measure, respectively. My Steyr, similarly (and with 71x71 degree geometry), fits a good 2-3cm "smaller" than it's 59cm top tube would indicate, yet tolerates a 110mm stem since I fitted a wider handlebar to control steering heave while riding off of the saddle.
Hard to believe this is all-day comfortable for a 5'9" rider, albeit one long in the leg:
|