topslop1

On a 58cm 2013 Synapse that feels too big for me. I'm 6'1'' wearing a 34'' pant inseam.

Would a 56cm be appropriate for Nashbar's carbon road bike?

hazben1

Know nothing about the Synapse but I do have a Nashbar CR-5. My previous bike a Nashbar CR-2 was a 58. When I compared the geometry of the 2 bikes I decided to go with the 56. If I remember correctly the top tube of the 58 was about the same size of the 56. Thus I decided to go with the 56. I don't know bike geometry as well as many on this site but, it seems the top tube length on the CR-5 is a little bigger on them compared to other bikes of the same size.

The 56 fits me great once I got a 120mm stem. For the record I am 6' tall with long arms and terrible flexibility. The bike itself I thoroughly recommend. Just wait till they have their 20% off sale so you can get the CR-5 for around $1400 shipped.

rms13

I don't think the Nashbar comes in a 56 so it would probably be the 55 which has a 565mm top tube. The headtube a a couple of CM shorter then a 56 synapse and about 4cm shorter then the 58. But I think the 55 would probably be a good fit but you should check out an online fit calculator and get rough idea of what frame geometry would be good for your body and look at the Nashbar's geometry chart

Maelochs

I think Nashbar publishes complete geometry charts for their bikes. No need to guess.

I am about the same size as yo, with a ridiculously short torso and abnormally long limbs.

When I was shopping for a new frame I checked out a lot of them, including Nashbar's and for almost all of them 56 seemed to be the sweet spot. That weould be my recommendation ... seeing as i don't lose anything if I am wrong.

Steve B.

Whatever the effective top tube is on your C-Dale, plus the stem length gives you some measurements as a starting point. If you need to be 30 cm shorter you probably cannot make that fit work with a shorter stem, so the next frame size that gets you where you want to be should work. The caveat is if you are currently running a 12cm stem as example, maybe a 10 would work. That's a cheaper fix then a new frame but the current stem length is important as well,

Kevindale

In what way does it feel too big? I think Steve B. has a good idea that may help. I'm 6' even, approx. 34" inseam, and ride a 58 cm CAAD10. It felt better to me than the 56 cm during the test ride, though it's always lacked a certain quickness in handling. I've wondered for a while if I would have liked the 56 better. Yesterday I swapped the original 44 cm handlebars for 40 cm, and moved my seat forward 5 mm, and the bike feels transformed. It feels quicker and smaller. If I wanted to tighten up the cockpit further, I have a cm or 2 I could drop with a shorter stem, but it's feeling great right now.

2lo8

They're very incomplete and usually don't include stack and reach.

Maelochs

I got out a ruler and a protractor and sketched out the geometry of the frame I wanted and made my own measurements for the missing numbers. Turned out later my sketch was sufficiently accurate and my estimations were close enough to make a valid choice

2lo8

That sounds needlessly difficult when you can plug in the numbers into a webapp to get estimates. You just have to be able to guess A-to-C, which you would have to guess either way.

Maelochs

which webapp? ... since I don't know that, I'd say doing the drawing was the better solution.

A link would be much appreciated.

AlexCyclistRoch

I'm 6'2", 34" inseam, and I feel cramped on any frame smaller than 60cm.

Maelochs

Which is why I usually recommend that people use the Bike Fit Calculator | Find Your Bike Size | Competitive Cyclist .... the OP mentioned that he was 6'1" and had long limbs ... which often indicates a relatively short torso. If you have a more standard build, obviously you would need a different sized bike.

benetga

I've got the 56cm 105 carbon. It fits me like a glove and with same height and inseam.

2lo8

There are several on the internet. This is the one I wrote for my stem calculator.

Reach and Stack Calculator

Maelochs

Thank you, sir.