Hello Everyone,

I was hoping you guys could take a look at some pics and see if anything jumps out at you. I'm trying to decide between a 52cm (black bar tape) and 54cm (white bar tape). The bike is a Specialized Roubaix. After a rough fitting, the LBS guy said that I could comfortably ride either size frame. So, I took each bike out for a test ride. They both felt good to me. He said he set them up with the same measurements. The only difference I saw was that the 52cm bike had a flipped up stem while the 54cm bike had it in the negative. That's just the way the bikes were assembled, and nothing he did intentionally. So, with that in mind, here are the pics. Hopefully they can be of some use. When I look at them, I don't see much difference in my body position...

Thanks in advance for taking a look. Let me know if I can provide any more information.

White Tape bike

Hi, the bigger bike, white tape, it's not too big, rgds, sreten.

I see a little more rotation of the torso on the bigger bike,
i.e. your lower back is tilted a little more forward, and
perhaps reading too much into just two pictures, for
the bigger bike your spine has a smoother curve.

For no reason, you look better on the bigger bike.
Thinking about it, a little more stretched out, racier,
at the same time you seem to look a little scrunched
up on the smaller bike, less natural, in comparison.

Thanks for the replies so far. When I left the LBS, we kinda settled on the 52cm, but he had to order one in from another store location because the one pictured was too expensive for my budget. And unfortunately, the 54cm bike pictured is cheaper than I wanted to go. So, he'd have to do the same thing again if I change my mind now. I don't think that will be a problem, but it certainly is a pain. I suppose it's worth it to get the right fit.

I agree with Sreten's assessment, but the 52 will be fine, the stem needs lower and longer, that's all.

I will definitely have to ride them both again. Maybe I'll ask the guy to flip that stem over to see if that makes the difference. I hate being in between sizes. Makes it hard to be sure. Thanks again.

It's not how you look on the bike it's how your perform; two words...Chris Froome.

That said, your center of gravity looks much, much better on the 54cm and you can always shorten the effective reach by flipping or changing the stem. On the smaller bike your butt is hanging out over the rear axle, not so good.

Both bikes felt good to me in terms of reach. At least on my short test rides. Even if I drop the stem on the smaller bike, I'll still have axel butt problem...

Color me daft, but what is the nature of this 'axle/butt' problem? What's the dynamic? I've never thought of it in a meaningful way, or as an important measure.

Based on my own experience, shorter wheelbases 'buck' a little more over big bumps than longer wheelbases, but in terms of negative impact on performance, I don't have any associations there, aside from feeling shorter wheelbases feel more sporty.

And this from a guy who rides a mini-velo and a folding bike, where my butt is not only way out over the axle, but the whole wheel!

Not sure either, but I have no idea what I'm doing. Based on the pics, which I'm sure do not convey the whole story, does one fit look more right to you? Seems most people here would rather see me on the larger bike.

And fwiw my measurements:
5"8' 3/4 tall
31 inch inseam

Speaking about road bikes, like the Roubaix, you want your center of gravity closer to the center of the bike. Too much of your weight over the rear and I think you'll experience the bike laboring in turns, climbing issues and not floating over bumps..more like riding a rear loader tourer than a road bike. As I read it, 50-60% weight on the back wheel is what pro riders shoot for, not to say we should worry about those figures. On the 52cm you look pushed toward the rear. Of course, it could simply be how you are fit on that bike, i.e. the saddle position.

True. My understanding was that saddle positioning was adjusted based on my leg extension. So I'm not sure that moving it forward is the right thing to do. It may just be that I need the larger frame. When I tried the drop position on the smaller bike, I got the sensation that I was leaning out over the front tire quite a bit. On the larger bike my weight felt more evenly distributed. Not sure if that is anything to go by.

+1 for the larger frame.

Well, it gets complicated from here. Saddle position fore/aft, up and down, determines whether your upper body is unweighted and you can efficiently produce power. You can find that sweet spot relative to the crank on different sized bikes, but if the frame is a mis-fit your center of gravity relative to the frame is in the wrong place and your reach to the bars may create shoulder and neck problems, or you end up cramped & slow.

I say, if you are going to plunk down good money for your #1 road bike get the opinion of a knowledgeable fitter to advise you about size up or size down on that frame. You won't get a do over, and riding a mis-fit bike can be a long term annoyance.

I like your proportions on the larger (white tape) 54 cm frame. I would recommend that you flip the stem upward, though, until you are more experienced on the bike. I'd also like to see more elbow bend and relaxed hands...

Thanks for your feedback. Regarding elbow bend and relaxed hands, is that something I need to do myself, or is it an adjustment of the bike?

Hi,

It comes with just riding a bike a lot, no effort.
And with bars lower than you start with, generally.

rgds, sreten.

Thanks, I will keep that in mind as I go.

Yes. It's intentional as to you hold your posture and engage your core muscles. Just relieves pressure from your hands/wrists. PG

Try a bigger one. Even w/ the 54 cm/white tape bike, you look a little cramped in saddle-to-bar dimension. Not bad but why not try a 56 cm? Get down in the drops and pedal hard, see if you can stretch out comfortably or if your midsection feels cramped, knees overlap elbows too much, etc.

Hadn't even considered a 56. I know with the 54 I can feel the top tube when I stand over the bike. Not uncomfortable or anything, but definitely there. I suppose it's worth a try.

As a general rule, racers will find that buying the smaller bike and making it longer gives them a better range of fit options, and handling characteristics that are preferable for racing. At the same time, a rider who is just looking to get out and enjoy the ride will likely do better buying the bigger size and shortening the reach if need be. One of the major determining factors for me is how hard you plan to push down on the pedals.

A racer will plan to put a lot of force on the pedals a good portion of the time, and because of this the legs will take a lot of weight that would go to the hands. As a result, you can ride a lower front end position without adding any weight to your hands. Also, a racer will need to get up and sprint. When sprinting, a higher bar/torso setup makes it difficult to get leverage to apply as much force as possible to the pedals. A smaller frame size with a longer stem keeps the rider low over the front wheel to increase steering responsiveness, and allows a lower bar position due to shorter frame stack.

A recreational rider is not typically putting as much force to the pedals, meaning that same low position results in more weight for the hands and back to support on their own. The bigger frame has a taller head tube, so the bars are easier to mount higher. Also, how the bike sprints is usually much less of an issue. This position will generally have more forgiving handling as well. Imagine you ride through a patch of sand... you will be more likely to emerge out the other side unscathed if you shift your weight back (which a larger frame size & shorter stem will help do), and this holds true to most handling situations that can get novice road cyclists in trouble.

In the end, your shop is right. You could ride either bike, and in most cases you would never look back and think "what if I got the other size". Judging by your comments, it seems you enjoyed the feel of the 54 better, so I am curious as to why you then ordered the 52... is there something that felt better about that size that you haven't mentioned yet?

PS - would it be the end of the world if you rode a 56 around? Not really. But for someone who thought the 52 was a better fit than the 54 to all of a sudden want a 56 would be a huge red flag to me. Your pictures above do give a vague idea of what your position is like, but there are too many variables in distance to subject and angle that I wouldn't draw any in depth conclusions about what adjustments I would make... but I see nothing at all in those pictures (and more importantly how you felt about each) to suggest trying a 56.

Since you are looking at Specialized, your shop almost certainly has a BG fitter. Talk to him or her. The shop clearly is not trying to simply sell you inventory that they have, as they are ordering either size anyways, so I would feel pretty confident that they are (1) unbiased enough to give you straight answers, and (2) in a better position to give you real answers than a bunch of people looking at one tiny snapshot online.

For once I agree with sreten. I think you do look better on the white tape bike, slightly flatter back - it allows you to be more stretched out, and probably has a little longer top tube, or what they now call reach (horizontal distance from the top of the head tube to a plumb line to the BB). I'd also think about fit evolution - how is your fit preference likely to change, barring abnormalities. Mainly, choose the bike for which your saddle is less slammed back, that has the shallower seat tube angle. You are in a moderately aggressive position on these two bikes, and I think you will want to dig in lower as you get used to the bike. That will probably result in slowly pushing the saddle back and down a bit, with the bars moving forward as you want to get more aero, with comfort.

Thank you for the in-depth reply. I am not a racer, and am not interested at this point in becoming one. That said, I do intend to do some real work on this thing. Lots of hills, mainly. And when it is flat I would like to push into the upper teens/ low 20s for as long ad I can. My terrain really won't allow much of that however.

I rode each of these frames one time, back to back. And I really do not have a good frame of reference for what a proper fit should feel like. When the LBS guy said either frame will work I simply thought smaller would be better due to the lighter weight. But reflecting back on my test rides after the fact, I started to recall some differences. Primarily when in the drops. Really, I need to ride both sizes again. And pay better attention to the differences.

This is what I intend to do later this week when I get back from vacation.

Yes I definitely intend to adopt a more aggressive stance on either frame. On an average ride I spend about 1.5 to 2 hours in the saddle. So likely will not want to go to the extreme. My typical 20-mile ride includes about 1,400 feet of climbing. And that also means some pretty extreme downhill too. Hitting 40mph + is something that can happen regularly.