Bike Fit
 

So I took some measurements and put them into the Competitive Cyclist Fit Calculator. Either I did something entirely wrong (checked all measurements multiple times, usually within 0.125 inches), or I am just not standard. Anyone look at this and think something is grossly wrong?

Also measured wing span at 72.625 inches vs 74 inch height, so -1.375 inch index.https://cimg1.ibsrv.net/gimg/bikefor...de45195826.png

I could never get that thing to work either.
I would say a starting point is a 58cm effective top tube, purely based on your height.
You should post this on the "Fitting Your Bike" section of the Forum.

You have really long legs and a short torso, so standard frames are not made to fit you,

But with a short stem and long seatpost, something will work.

"Endurance" frames will be best suited for fit.
Roubaix, Domane, Defy. Stuff like that.
They have less reach and more stack which will suit your long legs.
Don't let the endurance name put you off if you are looking to go fast.
They won't be any slower than a "race" bike and will fit you better.

I would check the inseam length.
You are about the same height as me, but your inseam is 2" longer than mine.

I have similar measurements. You can either get a roughly 58cm or 60cm stock frame and crank up the seatpost...or go custom geometry.

Be sure to triple check all your numbers first.

Thanks for the replies.

Put this in bike fitting, too, in case it gets a different crowd to see and comment.

I did the measurements several times. First time forearm length was a little shorter, making the TT shorter. Inseam should be very accurate as I've taken that several times, different days, different locations and gotten the same answer. All the others I've checked, too. Repeatability was within about 0.125 inches.

My hope was to look into a used bike as my first road bike, which is why I tried to use the calculator, but it seems like the recommended dimensions are very off from standard. More concerned now with buying used based on the numbers.

I was looking into endurance geometry before, so it makes sense to keep doing that, but looking at dimensions from the big three it doesn't seem like there is really that much of a difference between endurance and lightweight, at least not enough to shrink the gap in my numbers.

What kind of things could be done to help with the fit? I know shortening stem can make the bike twitchy and less stable (something some people want, but not necessarily me). Lifting the seat really high it sounds like will also push me into a more hunched over position. Is this where spacers are used to compensate? How high can that compensate for? What about crank length? If that was longer it seems like that would allow the seat to be more forward, lengthening the effective TT length?

What others fitting techniques would someone like me need to think about?

What measurement are you meaning?
60cm seat post, 58cm effective top tube.

https://cimg2.ibsrv.net/gimg/bikefor...d1aa2b41ed.jpg

The top tube numbers seem low to me. I'm similar size and hard to fit but I like a 59cm top tube. The best thing to do would be to get on a bike and see what you like and don't like about the measurements.
30 years ago I ran about a 4inch drop from saddle to bar top, now I can only handle about an inch or a little more. Not wanting to use a ton of spacers, I look for a frame with a 220 or 230mm headtube and I use an uncut steer tube.

What length stem?
What reach bars?

Both road bikes have 90mm stems, one has shallow shorter bars and the other has huge bars.

To get the bars as high as I want them I get big frames and end up with 90mm stems. I had a 63cm CAAD5 and it was a bit long for me but the height was good.

Ahhhh, both mine use 120mm stems.

The numbers seem low as in the calculator did a bad job fitting, or you think I put in the wrong numbers?

How does that work? I did try out a 61 cm diverge at a shop, but is it normal to walk in and ask to try it a few sizes of the same bike, i.e. a 58, 60 and 62 synapse, roubaix or domane? Or will the shop just get fed up with me? Is the handlebars should block the hub valid for reach? What should I be feeling for?

I assume the uncut tube would require buying a fresh tube. Do you just put a bunch of spacers? How do you feel about the 9 cm stem and the impact on handling?

So far the only frame I've found that has a TT less than the seat tube is the CAAD12, but finding that used may be difficult since it is newer.

Should I be more concerned with stack and reach vs. ST and TT length? I notice for instance on the Domane that going from 58 cm to 60 cm changes the ST by almost 2 cm and the TT by 1.3 cm, but the reach only increases by 0.3 cm while the stack increases by 2.1 cm.

Another reason is that if you look at for instance the CAAD12 vs CAAD13, the 58 cm on the 12 has a ST longer than the TT, which seems like what I want based on the CC fit, but it's Stack to Reach ratio is lower than the CAAD13 which had a ST less than TT. I chalk this up to other geometry differences, but it makes me wonder if stack and reach might be a more valuable metric to look for. Thoughts?

Reach cannot be compared directly, between two distinctly different stack heights. To get the correct comparison, assume that 2cm of spacers would be used on the smaller frame and that reduces the reach by about 6mm. The figure the difference in reach between the two frames.

If the bike shop gets fed up with you wanting to try multiple sizes, walk out and find another. With that said, if the bike shop was helpful, and you end up buying used, be sure to go back and throw the shop some business by getting some kit/tools/accessories.

Having to use a 90mm stem isn't going to suddenly make the front ends super twitchy. You'd probably notice a bit of a difference if you rode the bike back-to-back with a 110 and 90, but you get used to it/adjust quickly.
Also, stem length will have less of an impact on a bike with relaxed geometry (i.e. endurance) that it would on one with race oriented geometry.

Another thing to consider is handlebar choice...you could easily alter the reach +/- 10mm based on the shape of the bars (trek uses bars with an insanely long reach, for example)

Ideally, you want to find a bike that allows you to run a minimal amount of spacers, but yes, if you are buying used, then you do need to consider the height at which the steer tube as been cut. If it's too short, you'll need a new fork. Or find a different bike.

With todays sloping top tubes/modern geometry, you definitely want to focus on stack and reach...as you noticed with the CAAD's, seat and top tube lengths give you little insight into how a bike will actually fit

The spacers would be used to lift the stem? And you'd do that since the seat post would need to be 2 cm longer and to get the same position, you'd need to lift the handlebars 2 cm?

Not too worried about that. Spent $400 there the other week on my first pair of shoes and pedals and a balance bike and helmet for my daughter. I'm sure they'll get money from me.

I'll keep that in mind regarding the handlebars. Is there any difference in handling changing handlebars vs. stem length? What about stem angle (more upright would shorten reach while behaving like a spacer?) or crank length (longer crank means I can move the seat a little more forward to reduce reach, maybe?) as ways to adjust the for? Or do those cause more problems than they solve?

How much steer tube is usually available on new bikes, i.e. how much spacer could you typically add?

Most new bikes come with 30-40mm of spacers, but I'm a firm believer that you really shouldn't run anything more than 10-15mm. Any more than that and it really starts to effect the handling of the bike (bikes are designed around 0 degrees of spacing). If you need more spacers, then you're better off going with a larger frame (or a different brand/bike).

Handlebar reach is going to have the same effect, handling wise, as stem length...that is, when you are riding in the hoods. Switch to the drops, then handlebars choice will have a larger impact.

Stem angle (if you go with an extreme change, i.e. flipping it) will have the same effect as stacking up the spacers. Which is a lot more noticeable than changing the reach, since it raises your center of gravity, and shifts weight balance towards the rear (both very bad things for handling/stability). So again, if you find yourself needing to flip the stem, you need a different bike. Minor changes in the angle (i.e -7 to -10) can be used to fine tune your position.

Crank length should not be used as a way to alter reach. Crank length is chosen base on rider height/position/hip angles...if you ride in an aggressive position, with open hips, you'll need shorter cranks. In fact, going with longer cranks would require you to increase saddle setback, thus (slightly) increasing reach. Crank length is actually a very tricky, and often overlooked, part of bike fitting.

I have always been able to size my bikes well enough simply through Effective Top Tube length.

The 2cm of spacer would put the handlebars in the same position, relative to the center of the bottom bracket. Remember that stack and reach both reference the BB centerline.

New bikes come already lifted 3 to 4 cm, or they have enough tube to allow that?

I was thinking more increasing the angle a few degrees, not necessarily flipping it. Your points, though, make sense. It was just me trying to understand options for shrinking reach on a bike with an appropriate stack.

I'll stop considering the crank.

I guess in my situation I asked because based on ETT I'd be looking at a 56 cm frame as a 6'3" guy and that seems like a significant amount of spacers.

Thanks. That is what I meant, I just don't think I was as clear.

When test riding bikes, what should I be feeling for in the torso to know if the reach is good for me? I read that the handlebars should block your view of the front hub. Is that true? If I'm not particularly flexible, does that push me to a smaller frame?

I do the same. But “serious” size/fit experts say stack and reach is best.