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5'7" possible that a 51cm is a good fit?(11 posts)

5'7" possible that a 51cm is a good fit?kendoo
Sep 13, 2003 4:16 PM
My 53cm Bianchi XL Boron feels like it might be a little too long. I think I paid too much attention to what size bikes others in my group were riding and how tall they were etc. I now have a 90cm stem on it, and I often have to scoot my butt back on the seat to get to the "sweet" spot. Seems to me if I had a 51cm, I could run an average sized stem and be better positioned on the seat. This is the only road bike I've ever owned so I really don't know how comfortable I should expect to be. I don't trust the LBS to give me a good fit.
re: 5'7" possible that a 51cm is a good fit?MShaw
Sep 13, 2003 5:36 PM
Could be, could also be that you just don't have your saddle adjusted properly...

Been fit? If not, then start there. Ya gotta find someone that knows what they're doing!

Posting pictures here can be a start if you don't have anyone locally. We're not right there with you, and can't see every angle.

I'm 5'6" and ride a 52 cmTNRyder
Sep 14, 2003 8:16 AM
Based only on my cycling inseam of 32", I should be comfortable on a 53-54 cm frame. But, this does not take into account my shorter torso. (Most ppl with a 32" inseam are 1-3" taller than me.) Therefore, I need to ride a frame which appears to be too small for me on 1st glance. If you are going to err on frame size though, it is always better to err on the small side. If you have access to a good LBS, pay the money to get fit correctly. If your LBS sucks, don't buy your bike there. They have to earn your $$.
I'm 5'7" and all my bikes are 51cm........Dave Hickey
Sep 14, 2003 2:04 AM
They all measure 51 ctc and fit me fine. If your comfortable on a 51cm, go for it.
Agree w/MShawcoonass
Sep 14, 2003 3:33 AM
Go to a GOOD LBS and get properly sized/fitted....if it costs $100, it's better than buying another ride that isn't going to fit you. Personally, I'm only 5'-8" and my first frame was a 52cm and I never could get comfortable. Finally I went and got sized (Bio-racer) for a custom and it turned out that I needed a 55.5cm w/55.5cm top-tube, with a 100mm stem; now I ride in dreamland on every ride...
Get sized at a good LBSSEPARIDER
Sep 14, 2003 3:22 PM
I am 5'7" and the guy who fit me 5 years ago (I was a newbie back then) put me on a 56cm Raleigh R500 (budget constraints). He said I have a long femur. After reading so many posts from guys with my height, I've wondered if my bike is too big. But, perhaps not. After 11,000 miles and some long rides (178 miles in one day once) and with no show stoppers, I would say my fit guy must have known what he was doing. Don't be afraid to drop a few bucks for the fit. My LBS applied my fit fee to the price of the bike. Ask yours to do the same, it can't hurt.
re: 5'7" possible that a 51cm is a good fit?il sogno
Sep 14, 2003 3:53 PM
I'm 5'7" and ride a 53 center-to-top Colnago. It fits like a dream with my 110 stem. Before you spend any money, try moving your seat fore or aft on the seatpost. Maybe it'll all click in for you. Remember, too, that compared to a mountain or comfort bike, a racing bike will stretch you out more. All that stretching out is uncomfortable at first, but soon you appreciate the way it opens your lungs and shoulders. In any case, don't panic. Get out the wrench. Fiddle.
Interesting- Morphological differencesboneman
Sep 15, 2003 2:20 PM
I'm 66.5" in height with a 30" inseam. The past 30 years I've ridden bikes which are mostly 50 CTC. Most of my ahead set type frames are done with a 100mm 80 degree stem. I have a Litespeed Vortex which is about 49.5 ctc, also with a 100mm 80 degree stem and that's been my main ride for the past 5 years. I recently bought a C40 and was undecided between a 51 and 52, ctt as measured by Colnago. Fellow poster C40, apt moniker, was a great sounding board and I got the 51 which is 49 ctc. Fits like a glove. I also use it with a 100mm stem but 73 degrees. My best fitting bike thought is a custom Deda SAT 14.5 Corrado I had made in Liverpool. It's got a 73.5 degree seat tube angle (more set back than either the Vortex or C40), 52.2mm top tub and measures 50 ctc. Lots of toe overlap but that's really not relevant. If only it were carbon.
Possible, but it sounds like it's time to do your homeworkKerry Irons
Sep 14, 2003 5:00 PM

For adjusting the fit of the bike, there are roughly five starting points:

1. Seat height (top of saddle to center of pedal axle) at 108-110% of inseam.
2. Saddle parallel to ground.
3. Saddle fore/aft adjusted so that a plumb bob from the bony protrusion just below the kneecap passes through the pedal axle when the cranks are horizontal. This is known as KOPS (Knee Over Pedal Spindle)
4. Front hub axle obscured by the handlebars when riding in your "regular" position (drops, hoods, or tops).
5. Top of handlebars 1 to 4.5+ inches below the top of the saddle depending on your flexibility and size.

These are all starting points for "average" proportioned people, and many folks like to move away from these starting points as they learn what makes them more comfortable, powerful, or efficient. You want to get the fit of the frame as close as you can, then do minor adjustments with the stem, seat post, saddle position, etc.

A lot of this is personal comfort, and we all tend to adapt to a given position over time. For example, a given stem length may be right for you, but it may feel long at first. I use the "handle bar obscures the front hub" rule for my fit, but others claim better position (for them) with the hub in front of or behind the bar. I'm 6' tall and ride with 11.5 cm drop from saddle to bar, probably more than most people would like but fine for me. Some are suggesting zero drop from saddle to bars - it's about comfort, efficiency, and aerodynamics. The ERGOBIKE calculator is pretty good, but it is not infallible. I would suggest riding some miles (over 100 total, and over 500 would be better) and see if you adapt to the position. There are no hard and fast rules, just general guidelines, when it comes to these things.

Just as important as your size is your flexibility. If you have a stiff lower back, you may not be able to lean over and stretch out as much. If you are very flexible, you may get away with a longer top tube, with the stem in a lower position. Over time on the bike, too, you may become more limber, or at least become accustomed to being lower and stretched out. So, your first 'real' bike may not be anything like what you will want 5 years from now.

Someone new to road riding is highly unlikely to find their ultimate position on the first go. As they become accustomed to the riding position and get some miles in, sometimes over several seasons, people often find their desired position changing. What was "stretched out" now feels OK, or what was "just right" now feels cramped. With time, if you are working on your position along with all your other riding stuff, seat position tends to rise, handlebars tend to be farther below the saddle, saddles tend to move rearward, and handlebars tend to be farther forward from the saddle. You simply cannot say "this is the right position for someone of your body dimensions" because there are too many variables and things that change with time. Get used to your position, and then occasionally make small changes: raise/lower your saddle, move your saddle forward/backward. Ride a while with the changes (a few 100 miles, anyway) and decide if it is better or worse. If it is better, keep moving in that direction. If it is worse, try moving the other direction. If you don't try, you won't find out, but it is a long term process, often taking years, to really dial in your position. And since your strength and flexibility are changing with time, it is reasonable that your position would need to change also.
inseam not height...C-40
Sep 15, 2003 4:56 AM
Sounds to me like your ignored your cycling inseam, which is just as important as height. Try reading up on fit at

I'm 5'-6.5" tall with a long 83cm (32-5/8") inseam. I undoubtedly have a shorter torso than you. I ride a 54cm c-t or 52cm c-c frame with top tubes of 53-54cm.
I use 100-110mm stems depending on my saddle position.

The 53cm (c-t) Bianchi should not be too large. The TT length is only 52.5cm, IF the geometry charts are correct.

The Bianchi geometry chart does not make sense to me. On the 53cm frame they claim only a 50cm c-t dimension, with a 30.5 inch standover. This combination is impossible.

You should carefully measure your frame for c-t size, TT length, standover height and head tube length.

Changing to a 51cm size would increase the stem length required by 10mm, but the head tube may be 20mm shorter, which will require an increase in steering tube spacers and/or stem rise to get the bars up to height. This seems to be something that advocates of too-small frames often ignore - the stupid looking stem setup that's required to get a good fit.
Sep 15, 2003 5:25 AM
Opps, just noticed that the Bianchi has a sloping TT. That explains the c-t seat tube and standover discrepancy.

The bottom line is the same. The smaller frame would allow a 10mm longer stem, but if the head tube is 2cm shorter, the stem setup could be pretty ugly.

Perhaps you should experiment with saddle position and be sure that the saddle is not too far back. A 90mm stem with a 52.5cm TT is a pretty short combination.

The (typical) 74 degree seat tube angle may part of the problem. If you have long femurs and have the saddle back a long way to achieve the proper KOP, then a 90mm stem makes more sense. The shortest that I've used though, is a 110mm stem with a 53cm TT.

Have you ever checked knee to elbow clearance? If the knees and elbows overlap when riding in the drops, then your problem is probably not too much reach, just a lack of upper body strength and conditioning.