Looking for forum members' input (bike fit data)

[fa63]

Hey all,

I have been collecting published data on pro bike fit measurements for a while now. Some of you may have already seen the thread in the "Bike Fit" subforum (titled "Ok, how far off are you in this table?"), in which the chart summarizing the data is shown. Here is a link to my blog post, which has some additional data / most up-to-date charts as well:

http://ft-atalay.blogspot.com/2012/03/pro-bike-fit.html

Anyways, one of the ideas that came out of that discussion was to gather similar data for the forum members on here. I think it would be interesting for comparison purposes, and it might also generate some useful data/trends. Here is a link to a Google spreadsheet that I put together, where you can enter the data. I went ahead and entered my own information as an example.

https://docs.google.com/spreadsheets/d/13dnKstwHLiEdOqW7YqjvFiHm4_cAmR4CIRVe0I8l5xU/edit?usp=sharing

Look forward to seeing what might come out of this. If you don't have all the measurements, that is fine; just enter what you know. Suggestions on additional data points which you think might be useful are also welcome.

[echelon_john]

FYI the spreadsheet is view only as currently set

[fa63]

Oops, try now. And thanks for the heads up!

[gospastic]

I entered my info.

[fa63]

Thanks to everyone who put in their information so far. I also went ahead and added a chart to summarize the data as it comes in.

I will go ahead and share this on other forums I am a member of as well, to generate some additional data points. I think it would be neat to have a database where one can go to find riders of similar proportions, and see how their fit compares to theirs.

Cheers.

[stephenmarklay]

I will get this done.

[justindcady]

Very cool chart. Already starting to see the difference between "pro rider" type fits and what "non-pros" are using. On your initial chart plotting pro rider numbers, my reach was *way* shorter relative to what others with my height were running. After the first few submissions, I can see that I'm not running much less reach than what similar built riders are running. Very interesting. Will put my own numbers in later.

[tuscanyswe]

Done

But why are we using saddle tip as a reference point for anything? Seems like a poor data point to me.

[carpediemracing]

I'm putting in normalized numbers, i.e. off my SLR saddle. It helps that I had a Guru fit with the SLR so the dimensions measured by Guru are super accurate, although I don't know my exact inseam or saddle-pedal distance (I have to measure).

I've since moved to an ISM saddle.

Should I put both? The ISM saddle is wacky but if you have an "offset" based on the ISM model (different ISM models have different effective sit positions) that would normalize the numbers.

[fa63]

I agree it is not the best reference point (though it is useful because it is easy to measure from there), as it can change depending on saddle. That is one reason I asked for the saddle type, to try to correct for some of that. I might add another column asking for the measurement from the widest part of the saddle.

[fa63]

I'm putting in normalized numbers, i.e. off my SLR saddle. It helps that I had a Guru fit with the SLR so the dimensions measured by Guru are super accurate, although I don't know my exact inseam or saddle-pedal distance (I have to measure).

I've since moved to an ISM saddle.

Should I put both? The ISM saddle is wacky but if you have an "offset" based on the ISM model (different ISM models have different effective sit positions) that would normalize the numbers.

Please put in both. That way, I can try to see if my normalization scheme based on saddle type works.

[benb]

Put myself in.. I am way below the reach line as expected. Right on the saddle height line. I might be able to extend my reach as things are working pretty well in my current fit but no way could I extend it to the point I was on the reach line, that would be extending my reach close to 6cm, no way in hell that is going to happen, I've already had way too many shoulder/upper back issues from stretching out more.

[fa63]

benb - you will notice you are not the only "reach-challenged" person on the list. There is another person @ 185 cm with a reach not too far from yours (although it is interesting to note that entry ranked themselves as being short-legs/long torso).

We are up to 26 entries now. I was hoping to get at least 100; more would be even better.

Thanks to everyone who has contributed so far.

[gospastic]

Curious if you could make a chart for bar drop?

[fa63]

Done; see Chart 3. As I expected, there is really no good correlation there.

[echelon_john]

Come on, tall guys! It's lonely out there at the end of the curve! :beer:

[benb]

Nice work this starts to get really interesting the more data and charts it has.

[fa63]

Thanks, I hope others find it useful as well.

And echelon_john is correct, we need a few more people 1.88 m to 2 m (and 1.75 to 1.77 m) to fill in the gaps :)

[Black Dog]

Posted my data. This is a great thing you are doing. Very informative and interesting. Thanks.

[wallymann]

are you measuring saddle-bar drop to the bar centerline or upper edge?

[fa63]

Upper edge

[KJMUNC]

Just posted mine as well. Not as far out as echelon_john but definitely to the far right. Interesting stats.

[ergott]

I'll have to verify my inseam measurement, but I'm pretty sure it's correct. I do prefer a lower saddle height in comparison. I do know full extension I have a slightly dropped heal and it really feels right to me. Definitely not a toe pointer.

[tuscanyswe]

I'll have to verify my inseam measurement, but I'm pretty sure it's correct. I do prefer a lower saddle height in comparison. I do know full extension I have a slightly dropped heal and it really feels right to me. Definitely not a toe pointer.


Same here.

[8aaron8]

Every day I go back an look at this I feel less and less like a disproportioned rider:D

[Black Dog]

Every day I go back an look at this I feel less and less like a disproportioned rider:D

Haha, I was thinking the exact same thing. I start to feel like I belong when my data point is close to the trend line. :D

[mbrtool]

did it

[fa63]

I'll have to verify my inseam measurement, but I'm pretty sure it's correct. I do prefer a lower saddle height in comparison. I do know full extension I have a slightly dropped heal and it really feels right to me. Definitely not a toe pointer.

Same here.

Thanks guys. I am just trying to do spot checks to make sure data is entered correctly; not trying to eliminate outliers or anything. This is good information too.

[wallymann]

Upper edge

cool. i updated my data and added a comment clarifying that spec.

[fa63]

It seems we have stalled out at 37 entries. Given that there are over 700 thread views here alone, was hoping for a little higher participation but oh well. I will bump this up again, as a gentle reminder to take some measurements and add to the database over the weekend :)

Based on what has been entered in so far, I think some interesting patterns are starting to emerge. Perhaps the one that stands out the most to me is the fact that cycling inseam does not appear to be a significantly better indicator of saddle height than just the rider height (Chart 1 vs. Chart 4). The fact that it is more difficult to measure inseam than height could be factoring into this, but interesting nonetheless (to me at least).

[ergott]

cool. i updated my data and added a comment clarifying that spec.

As did I. I usually keep records to bar center back when 31.8 wasn't standard.

[Mark McM]

Based on what has been entered in so far, I think some interesting patterns are starting to emerge. Perhaps the one that stands out the most to me is the fact that cycling inseam does not appear to be a significantly better indicator of saddle height than just the rider height (Chart 1 vs. Chart 4). The fact that it is more difficult to measure inseam than height could be factoring into this, but interesting nonetheless (to me at least).

Well, there are a number of factors that neither height nor leg length account for that affect saddle height. These include foot length, shoe sole thickness and pedal cleat stack, saddle shape, and pelvis shape and tilt.

Unfortunately, none of the measurements in the table are fully direct measurements of bike fit dimensions, so there will always be measurement error bands. For example, BB to saddle top isn't really a measure of effective saddle height, nor is peddle top to saddle top, for that matter. Missing are the effects of cleat stack height and shoe sole thickness. Likewise, saddle to handlebar tops isn't a full measure of reach, because handlebar reach and brake lever shape also effect total reach. While pedal and handlebar dimensions might easily be included in the measurements, far less easy to measure are the effects of saddle shape, which interacts in a more complex way with the cyclist's anatomy. Perhaps the only way to get a true measure of cyclists fit is to measure the cyclist themselves (from a fixed set of anatomical points) while sitting on the bike.

[fa63]

Those are all very valid points. Plus cycling is a dynamic activity and these are all static measurements, but I think having this data is interesting and insightful nonetheless.

[drewellison]

I have yet to enter my data, but I have good intentions to do so. Maybe this weekend.

Just for fun, I think I'm going to set up one of my bikes at the "average" setup for my height, just to see how I'd feel if I were average. That means I'm going to have to slide my saddle back about 1.5 cm and drop my bars by 2.5 cm.

I hope I don't hurt myself. :no:

[fa63]

I would try the increased setback, but probably not the increased drop. The average in that case doesn't mean much, as you can see from the scatter in the data :)

[drewellison]

I would try the increased setback, but probably not the increased drop. The average in that case doesn't mean much, as you can see from the scatter in the data :)

I'm sure that's good advice. My back was hurting just thinking about making those changes! I was sure a visit to my chiropractor was in my near future.

I will definitely try the setback setting, for fun, at least, if not for serious consideration.

And yes, I might make the change in stages, or at least take it easy on a few rides just to get the feel for it.

That's the problem with having n+1 bikes. You make a fit change on one, then you have to do it on all the others, or keep track of which ones you've changed and make those changes over time. Arrgghhh!!! :crap:

[fa63]

Giving this a bump, in case anyone else would like to contribute (see link to the spreadsheet in my first post in this thread).

[fa63]

Here is a quick chart summarizing the findings so far:

https://c1.staticflickr.com/1/488/32653792696_59f5841213_c.jpg

On average the saddle height is virtually the same across the spectrum, but the pros reach a little bit (1-2 cm) longer...

[gregblow]

can you update the spreadsheet? i don't see anything. thanks

[fa63]

It works for me. Here is the link again:

https://docs.google.com/spreadsheets/d/13dnKstwHLiEdOqW7YqjvFiHm4_cAmR4CIRVe0I8l5xU/edit?usp=sharing