Dull frame sizing question
 

Hello :), I hope you can help me sort out my problem!

Last year, while working as a bike messenger in London, I decided I wanted to get a proper road bike (rather than my single-speed), for leisure rather than work. I am slightly out of proportion, so I went to a bike fitting place to sort stuff out. They told me that according to my leg length, I need a 59cm frame, but because of my proportions ( I am 6ft), I should go with a 58cm and install a short stem. The exact specs they gave me are here: http://img269.imageshack.us/img269/8...itgeometry.png

I had heard that cyclocross frames had particularly short top-tubes, so I bought a 58cm 2006 specialized s-works tricross off ebay for a good price. The specs can be found here: http://www.specialized.com/us/en/bc/...sid=06TriCross
I set it up according to the specs from the bike fitters, and I needed a 50mm stem to make it work. The twitchy steering caused by this, and the annoying cantilever brakes that were on the frame, made me consider buying a different frame.

I am looking to buy a road frame with rack eyelets such as this one: http://www.ribblecycles.co.uk/produc...ue=RIBBFRAW200
and switching all of the parts over. The specs for this frame are here: http://img7.imageshack.us/img7/3184/ribblegeometry.png Can anyone advise me which size to buy to fit my bike fitters specifications?

I realise that this is a particularly boring thread, but would appreciate any help given.
Thanks in advance. :thumb:

a short stem would be in the 80-100 mm ballpark for your 58cm frame. unless you have lobster arms.

If you need a 50mm stem you bought the wrong sized frame.

You're sizing is very similar to mine. I run 80cm to top of seat and about the same setback. HB drop is same and I usually run about 57..58cm of reach. My opinion is that stem length needs to be relative to the frame size. For a frame in the 58/60 range, a 90mm would be as "short" as I would go and 130mm is starting to be pretty long. But for a 50cm frame, a 60mm stem would probably be fine.

You should be able to make a "square" 58x58 work with about a 100mm stem or so. Were you trying to set up reach at the minimum or more toward the middle of that range on your size sheet?

I think the measurement 'D' is to middle of handlebars/back of hoods rather than a range. Basically, the frame I have at the moment has a 58cm top tube, and the 56 ribble frame also has a 58cm top tube, but all the other angles really confuse me. Will the ribble frame also require a short stem? Thanks for the quick replies!

It looks like you've got longish legs and your fitter is trying to get you a more upright position. That's not an easy order to fill. If you get a larger frame to keep your "C" measurement in spec, your "D" measurement will be too long. The opposite happens with a smaller frame.

You really need to work directly with a fitter to make your selection. The alternative is spending some time doing some geometry and trigonometry, learning to read fit charts, and making the best comprimise on your own.

My suggestion is to go to your LBS and have them fit you to a Surly Crosscheck. It meets your requirements and any bike shop in the country (assuming you're in the US) can order one at a reasonable price.

Looks like im going to have to get my calculator out then!