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pro sizing(20 posts)

pro sizingpkompath
Oct 22, 2001 8:28 AM
What is the deal? Can anyone tell me the typical bike size of a pro racer. Why the super long stem? It seems that all of their bikes are way too small.
re: pro sizingTJeanloz
Oct 22, 2001 8:34 AM
The funny thing here is that all the pro's I know ask: "Why do most people buy bikes that are too big for them? Look at how short their stems are."

There are advantages to a smaller frame, primarily that they're stiffer and lighter. Also, racers covet a flat-back position that most people in the world find uncomfortable. The smaller frame puts the handlebars lower relative to the position of the seat and puts the body in a better racing position.

Most recreational cyclists have a position different than this and think their position is better. Pro cyclists think the rec setup is terrible. But it's different strokes for different folks- what pros do with their bikes is different from what average cyclists do, and the position reflects that difference.
re: pro sizingpkompath
Oct 22, 2001 11:02 AM
So, if Im 5'8" w/ an inseam of 29", then I should get a frame size between 50-52 cm.
re: pro sizingcioccman
Oct 22, 2001 11:15 AM
Beware, Italian bikes, generally, are measured c - c. Therefore, you can count on typically another 2 cm's to get a c - t measurement. If you're a 29 inseam, a 52cm Italian will be essentially 54cm c - t with a 54 top tube, and probably far too large for you.

I have a 30 inseam and feel a 51 cm c - t and 52.5 top tube c - c is a great fit. I've ridden larger in the past thinking it's fine, that was, until I got on smaller bikes.
re: pro sizingDave Hickey
Oct 22, 2001 11:37 AM
Just curious CIOCCMAN, we are the same size. What size stem do you use? I'm riding a 53.5cm top tube with a 100mm stem. I'm also 43 and I don't like being stretched out as much as I used to.
100 cm Cinelli Alter here, I prefer a shorter tt as well. nmcioccman
Oct 22, 2001 11:49 AM
Error above! 100mm, of course. nmcioccman
Oct 22, 2001 11:51 AM
Probably but....Dave Hickey
Oct 22, 2001 11:33 AM
A 50cm-52cm sounds right but are you sure your inseam is 29"? Inseam is not pant size. Use the book method to measure your inseam. It helps having another person. Have the person take a book and put it up in your crotch. Have them hold the book while you move. Measure from the top of the book to the floor.
re: pro sizingVelocipedio
Oct 22, 2001 2:00 PM
That's my size [body] and my size [bike]. Fits me beautifully.
TJeanloz does it again!cioccman
Oct 22, 2001 8:42 AM
You nailed it! More good stuff. Look at the pros arm angles. I also believe most rec riders get bikes too big.

Down below there are 5'7" guys with 30 inch inseams looking at 53, 55 and 57's! LOL Man, if they're going Italian, those seat tube measurements will be approximately, from center to top, 55, 57 and 59 respectively. No way will a 30 inch inseam rider have ANY standover clearance whatsoever on a 55 c to t seat tube.

I'm taller than 5'7" and find a 53 c to t seat tube and a 53.5 c to c top tube too large a bike.
I agreeDave Hickey
Oct 22, 2001 9:27 AM
I'm the same size. A 53 c-c is too big for me. I like between at 49 and 51 although a 49 requires a lot of spacers for me to be comfortable.
I agree 2Tig
Oct 22, 2001 10:42 AM
A long time ago, in a galaxy... no, I mean about 15 years ago, my first 2 road Cannondale Criterium frames were 54.5's. I'm 5' 7", 31.5" inseam. I'm lucky to have been able to father a kid since! I wondered why the seat tube never stuck out as much as most other riders... DUH! There just wasn't as much information availabe to me back then I guess. At least the top tube length felt good.

I started riding 52's later and am on a 51 now. Depending on geometry, I ride either a 51 or 52 C-C. I've never gone back to that horse trader/LBS owner since! It helps KNOWING what fits after riding a few years instead of having to depend on a not so honest LBS.
re: pro sizingMel Erickson
Oct 22, 2001 9:04 AM
My bikes have been getting smaller over the years. I started out with a 61cm Panasonic, went to a 60cm Cannondale and now ride a Softride that's probably equivalent to a 58cm (all measured c-c). I also just bought a medium Giant XTC NRS1 mountain bike. I've got a fair amount of exposed seatpost (not beyond the limit) but feel real good on this bike. Most would say that at nearly 6'2" with a 34" inseam I should ride a large but I like a smaller, lighter, more rigid frame, especially on a full suspension rig.

Over the years my position on the bike has changed but generally I've developed a preference for a lower, flatter back, even on the MTB. Smaller frames help with this.

It just depends on what you're after. The pros are certainly after something different than most recreational riders and would, therfore, have different tools to do the job.
Try fitting me, I'm 3 inches shorter with the same inseam.JS
Oct 22, 2001 12:02 PM
I finally quite listening to the so called experts and ended up with a bike that fits well. I ride a square 56cm with a 110mm stem. My only problem is spacing up the stem so I don't have such a drastic seat to bar drop. Iv'e had a bit of a revelation lately thanks to my MTB. I recently purchased a new frame with a 24" top tube( long for my size) but with a drastically sloping top tube I have plenty of standover height, this coupled with a short 90mm stem gives me an excellent fit, something I'm thinking about trying on a road bike.
Custom builder would be righteous for you.cioccman
Oct 22, 2001 12:15 PM
Bike companies set up their geometries to be somewhat neutral to what they believe the *average* person would be able to get on. Anyone outside of that will be best suited with a custom builder. Those on the fringes can modify with seat post types, length and height of stems, seat placement and height, etc. If you'll look at frame geometries, you'll find most of the builders utilize geometries that are quite similar. I have had Italian and American bikes that were called different sizes but were built to the exact same geometry.
re: pro sizingDEANguy
Oct 22, 2001 1:26 PM
Interesting. I went from a 57c-t to a 58c-c and love it. My measurements are 34in inseam and just a hair over 6ft. I have the position the same, but like using a 110 stem instead of the 130 with a shorter top tube. I feel more "centered" on the bike(that's the only way I can describe the feeling). I know the bike is larger, but it does not feel any larger.
re: pro sizingMel Erickson
Oct 23, 2001 6:25 AM
Sounds like you went to a slightly more upright position or, at least, a less stretched out one. I think torso length and arm length are more important than leg length in getting a proper fit but there are so many variables to deal with that coming up with a formula is difficult. A smaller frame usually gives more drop and a flatter back. Earlier this year my back was acting up. Since I've got a quill stem I could raise it a bit, adjust the angle of the handlebars and give myself a little relief. When my back got better I returned to the original position (slowly, over two weeks). I'm not sure I'll ever go to threadless on my road bike, as long as there is a decent selection of parts. I usually find myself adjusting things and the quill stem gives me that.
re: pro sizinghslilly
Oct 23, 2001 9:52 AM
I'm looking at buying my 2nd bike.
1st: ST: 62cm
TT: 59.5
Fit kit at the time said ST 61.8 TT 58.5
Now I feel this bike is too big.
Using wrench science web site and trying to "see" the smallest measurement it says ST 61.

I am 6'2" 34" inseam. Thats 36 - 37" crotch to floor. Id like to go 61 or smaller. Maybe buying off the rack. Bikes >60 are rarely stocked.
Smaller bikes have smaller TT how do you get flatter?
re: pro sizingMel Erickson
Oct 23, 2001 11:12 AM
get a longer stem, lower your bars, put your seat back, get a setback seatpost. These are all ways to stretch out, get lower and flatten your back. However, these adjustments may compromise other relationships, especially moving your seat back. I wouldn't recommend doing them all, certainly not at once and certainly not at the expense of an overall good fit. Generally you're correct, smaller bikes have smaller top tubes as compared to larger models of the same bike. However, a bike from another (or maybe the same) manufacturer in the same ST size could easily have a longer top tube. Much depends on the angle of the seat and head tube.
re: pro sizingguido
Oct 22, 2001 12:23 PM
One poster says he liked the top tube on his too-big Cannondale. Another thread complains about upper back stress hunkered down on his road bike.

Well, I have two frames that are by racer standards too big. I'm 5'8" with 32" inseam riding one 54 cm C-T and another 55 cm C-T. I have a 135mm stem on the 54 and a 120mm stem on the 55. I prefer a roomy cockpit. With the handlebars only about 2 inches lower than the saddle, I don't need spacers to jack up the stem. I can make my back flat. My upper body can pivot from the tops, hoods or drops, without scrunching or stretching. I can easily go from one to the other without bending my back. In the drops I can make my back as flat as the racers, but recovering or riding easy, I can sit more upright, back still flat, and stretch the upper body muscles, including neck. Longer frame tubes soak up more road vibrations, well built larger frames are just as responsive as smaller ones, and the weight differences are in grams, not pounds. Rivendell bikes has an interesting essay on frame sizing that y'all outta read.