Originally Posted by
MegMC
I followed the advice of @
Salamandrine and entered my very comprehensive measurements into the fit calculator at
Competitive Cyclist and here's what I got:
I made my husband measure my inseam/PBH multiple times because I could not believe it was 32" and my height was only 5'5"! Thus I am being recommended a seat tube length that is considerably longer than top tube, which does not seem to be how most frames from this era are built. Most geometry charts I've looked at for frames like Bridgestone, Centurion etc show top tube within 1 cm of seat tube c-t, and I understand the Italians may have an even more stretched out ratio.
So I'm assuming I can use quill stem and seat post adjustments on a slightly shorter frame to achieve good extension and more moderate/relaxed geometry while keeping my top tube more in the optimum range?
Today I have become intrigued by Bridgestone and the cult of RB-1, and my husband has proposed a plan by which he will upgrade his group set and sell me his Ultegra group for a very fair price :-) not sure about that. There is currently a 54cm 1988 RB-1 for $500 on Craigslist, which I think @
Salamandrine posted here above, and a 1989 RB-1 frame - to my eye the only one with a somewhat cool paint job - for local pickup on
eBay for a Buy Now price of $429 ( which seems pretty high. I would be willing to pay a bit of a premium for the paint, the cult and the smaller size but not sure how high - also not sure if the 80s RB-1 are quite as sought after as 90s). Also a very nice looking
Miyata 912 which is also ovepriced at $425 - how would a Miyata of that level compare to the RB-1. I assume there is limited potential for tire width. At these prices I'd probably be better off buying a brand new Soma Stanyan frameset from Velomine for $350. But then I wouldn't be C&V!
still much research and looking to do. Have not even dived into European bikes ....
Bridgestones from that era always had longer top tubes. They fit people with longer torsos and shorter legs the best. This isn't you. People are really all over the place, but women tend in general to have longer legs relatively, so your measurements aren't at all unusual. Once you get to the smaller sizes it becomes impractical to reduce top tube length and keep 700c wheels.
The thing to do is get a frame with a ST and TT length close to your range. I'd say go for a 55cm (C-T) frame with a relatively short TT. Make up the difference by using a shorter stem. For example, if the CC calc is telling you to run a 10cm stem with a 50.5 TT, and the bike you find has a 53.5cm TT, then run a 7cm stem instead. You will probably have to split the difference a bit, IOW go for a frame at the smaller side of 'Eddy' fit, and go for a bit more seat post extension but a shorter stem. I suggest not pushing the small frame thing too far if buying a vintage level top tube frame. That is to say don't buy a really small frame and run a long seat post. You'll have a badly fitted bike. "Eddy Fit" is a good middle of the road sizing.
If you do go for a modern retro frame like a SOMA Stanyan with a
sloped top tube, subtract a few cm from the seat tube size. In this case to go more by the TT. They are meant to use longer seat posts. You'd ride the 52 probably. Not a bad way to go BTW. Prestige tubing is great. Equivalent more or less to Reynolds 725 or the old 753. Add an Ultegra group or something similar and you have a nice modern bike with many of the best qualities of old steel bikes.
RB-1 were nice bikes with top shelf frames, and IMO more comparable to a pro Miyata than a 912. Again I'd recommend leapfrogging past the semi pro range. Go directly to top end. C&V racing bikes were about 21lbs on average. My Masi was about 20 lbs even with race wheels, 21 with training/general riding wheels.