Bike Sizing Help

A road bike I’ve been eyeing has come available on eBay. I ride a 56, but the one for sale is a 54. Is going down one size a big deal? Or can I simply get a longer stem. And other accessories to make it work? Thanks for your thoughts.

I would not. You could probably make it work, but in the end, you won’t be 100% happy if the bike doesn’t fit. I had the opposite situation. I was fitted at my LBS for a 58, found a sweet deal on CL on a 61. I swapped to a shorter stem. It works, but in the long run is too big.

it depends on your flexibility: when the fork is cut low, you could have a problem.
when on a 56 your stem measures for instance 130, i would stay away from sizing down;
if however it would be on a 56 100 mm , i would opt for the smaller framesize.

One problem you also might encounter is touching the front wheel with your feet when you start-stop or make very small circles…

I have a 100mm stem on my 56. Also, I have relatively short legs for someone 5’11", if that helps.

if you have relative short legs and a 100mm stem i would definatelu get the 54, especially if you are planning to set it up for triathlon with aerobars.

54 vs. 56 means nothing since bike companies use different measurements. This is ‘supposed’ to be the virtual top tube measurement, but who knows. I ride a 54 Cervelo road bike, 53 Felt, Size Small Ridley, etc.

This is ‘supposed’ to be the virtual top tube measurement, but who knows.

Unless I’ve really been living in a cave top tube length might be more important but traditionally seat tube length is the size.

I would be purchasing the same brand as my current road bike - just a different model.

So what differences would I notice on a smaller bike and can I offset those differences by getting a longer stem? Thanks.

What follow is very general.

You probably could get the saddle in the same position relative to the bottom bracket. You probably couuld fix any cockpit issues with a longer stem. The key word is probably. As a earlier poster said, ultimately the bike would be too small.

I’m a firm believer that a 110 or 120mm stem is proper in most cases. Since you’re currently using a short-ish stem on the 56, it may be a bit large for you and the 54 may work. That said, I’m 6ft and ride a Litespeed Ultimate 59 and a Look 585 XL - both with 130 stems, but not much setback. I previously rode a Cannondale 58 with a 130 stem. So, I’m a bit surprised you’re on a 56, but we’re all different.

If you can test ride a 54 at the LBS, do it. If not and the 54 is such a screaming deal that you could easily resell it, take a chance. Otherwise, I’d pass.

Hmm…maybe I’ve been on the “wrong” size bike this whole time…