Thursday, August 5, 2010

Specialized Roubaix S-Works fit?

Andy Klemm is considering buying a Specialized S-Works Roubaix which is a very nice bike. His problem is that he is not sure which size to go for as he has a long back and short legs. He has it down to either the 56 or the 58, we run through the options.
Question: I am interested in a Specialized Roubaix S-Works hoping it
will be easier on my lower back than my 56cm Giant TCR2 but unsure
about which size to buy. I am 6ft tall which would put me right
between a 56 and 58cm frame size. However I have a long upper body and
short legs for my size. Which size would you recommend?
Hi Andy.
I can see your problem, the choice between the longer top tube, also with the longer seat tube, or the shorter seat tube and the shorter top tube. You say you have short legs and long back which would suggest that the larger frame could be the best option as the top tube would suit your longer back, but this also means that the saddle will be low on the frame to take into consideration your shorter legs.
The seat tube length of the 58 is 540mm as opposed to the 56 which is 515mm and the horizontal top tube length of the 58 is 582mm and the 56 is 565mm. So there is quite a difference between the frame sizes.
Roubaix Frame Set
Personally I would go for the smaller frame with a long stem to accommodate your longer back, this would set up would feel more lively, be slightly lighter and look better. A large frame with a short stem and the saddle set low looks ungainly and does not perform as well. A lot of this also depends on the weight distribution on the bike, the short stem on a large bike makes you sit with more weight at the rear of the bike, where as the smaller frame should keep the weight more balanced.
The best thing you can do is to measure you old bike from the nose of the saddle to the centre of the handle bars and from the bottom bracket to the top of the saddle, then comparing your measurements with the two frame sizes you can work out what length of stem you will need and how much seat pin will be showing above the frame. The longest stems available are 140mm; if you need one longer then you will need to buy the larger frame.
I hope this all helps?
S-Works Roubaix Bike

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