Trying not to waste more money on bike fits

Discuss light weight issues concerning road bikes & parts.
robeambro
Posts: 616
Joined: Sat Jul 07, 2018 6:21 pm

by robeambro

Meanwhile, I'll try to bring my thread back to bikefitting :lol:

I tried both the the Emonda H2 56 (I think 2017 model, it was dark blue and had Ultegra mechanical and rim brakes) and the BMC TeamMachine SLR01 54. Admittedly, I tried the BMC only for some 15 minutes, while I had a 2h ride on the Emonda. The BMC had a 110mm stem and a bit of a spacer tower, while the Emonda had a 100mm stem and was moderately slammed. Given the larger stack on the Emonda, I would expect them to be around the same in terms of saddle to bar drop.

Now, as soon as I got onto the BMC, I felt it to be fine. I didn't feel too stretched, and seemed the right size for me. As soon as I got onto the Emonda, I instantly felt stretched, and ended my ride with a sore back and neck.

I came home, sure to find some big difference in reach / effective top tube / whatever.
What I see instead is,

TeamMachine. 386mm reach, 550mm effective top tube, handlebar reach 77mm, and again, 110mm stem
Emonda. 387mm reach, 560mm effective top tube, handlebar reach (? maybe 93mm), 100 stem.

Now, unfortunately I am not 100% sure on the handlebar reach for the Emonda. And I can't be sure the saddle setback was the same (my gut feeling is that I was slightly more far forward on the BMC).

If you ask me, I don't see a massive difference (even if, as a rough and meaningless metric, we check effective top tube + stem length + handlebar reach, the Emonda was around 15mm longer than the BMC, not an awful lot). I am now also reading that head tube angle affects the calculations, not sure exactly by how much.

How would you guys go about comparing these two bikes?
Is it normal that I felt much better on the BMC, and why?
Is the effective top tube a meaningful metric anyway?
Last edited by robeambro on Sat Nov 24, 2018 5:51 pm, edited 2 times in total.

cro2
Posts: 48
Joined: Fri Oct 13, 2017 7:39 am

by cro2

There's more parameters that will determine your position on a bike than stack and reach. The saddle height, saddle type, seatpost offset, amount of spacers, stem length, bar reach.. If you knew those exact numbers then you could compare those two bikes, but based on the stack and reach only one can say that it would be possible to set up both bikes in a comfortable manner for you.

by Weenie


RocketRacing
Posts: 940
Joined: Thu May 10, 2018 2:43 am

by RocketRacing

mpulsiv wrote:
Sat Nov 24, 2018 5:32 am
Your first reply wasn't enough to prove me wrong so you are back to make it crystal clear with slew of irrelavent examples? :smartass:
Yellow cleat is the stock cleat that comes with pedals. Most riders don't bother seeking an alternative, nor do they bother replacing insoles with medium-high arch. The fact is ~ 60% of the population have medium-high arch. Yellow cleat are advertised as 6° of float but it real world they float close to 9°. Not to mention they have lateral float.
Based on years of training and racing, yellow cleats always felt sloppy. Feet don't feel planted like with blue cleat, better yet red cleats.

You can ride what you want. No need to bring up Froome, Sagan or my mother into this. Oh, wait you also said something about jacka$$?
Hey man, you made a post about judging rider experience levels based on cleat choice... someone zinged you about Froome’s cleat choice, i piled on for entertainment, you claimed your views only applied to you as a rider, you took a shot at my reading comprehension (ironically most took your original comment the way i did, as a generalization to all riders... lots of irony), and i took the “judge a rider by cleat choice” to a more logical and more humerous level (adding “your mother” is an oldie but goodie, no pun intended). You took the bait hook, line, sinker, and here we are.

Your final point about me riding “what i want” is a great one. That was the point of the froome comment originally... cleat choice has more to do with riding “what we want,” and is a poor indicator of rider experience or skill. But you are right, if most pedals sold are brand x, and they come with say “pink” cleats, most riders (beginner included) will have pink cleats. So maybe your original generalization on judging rider experience based on cleat color has some statistical merit when applied to all bike riders, and not just yourself.

Of interest, My last set of pedals came with two sets of cleats with different floats (for the record, i took the more “pro” choice with moderate float... like my buddy froomie. The color also matched my bike which science says is good for 3watts).

But, i think we can both agree that experience, trial and error, and expert guidance can help guide someone to find the setup that is best for them (i.e. “what you want”). Bell curves dictate that the middle option will statistically work best for most, but it is not necessisarily best for the individual “you”.

My advice to the op is to try a few options, and see what feels best. I would advicate starting with the middle of the range float and arch support, and go from there. Ironically, many pro rider choices come from “what they are used to”, so some of them can be a funny bunch, and some can be slow to adopt to change.

Now... sock choice and length... THAT is a very accurate measure of rider skill/experience, once you correct for temperature and hookers.


Also, beard length is a DIRECT relationship to the likleyhood of hipsterism and fixie ownership. The only confounder to my model is correcting for homelesness...

robeambro
Posts: 616
Joined: Sat Jul 07, 2018 6:21 pm

by robeambro

cro2 wrote:
Sat Nov 24, 2018 3:40 pm
There's more parameters that will determine your position on a bike than stack and reach. The saddle height, saddle type, seatpost offset, amount of spacers, stem length, bar reach.. If you knew those exact numbers then you could compare those two bikes, but based on the stack and reach only one can say that it would be possible to set up both bikes in a comfortable manner for you.
Fair enough, but is it possible to calculate some metric that would be more comprehensive than reach / effective top tube? Looks to me that they hardly mean anything.. The BMC ends up being a few cm shorter (I am guessing around 3cm? Who knows) once we take into account a broader picture..

And yes, in theory one can say that it would be possible to set up both bikes in a comfortable manner for you. In practice, however, many bikes, especially in the aero realm, can only fit proprietary handlebars for example.

jih
Posts: 262
Joined: Fri Jan 29, 2016 12:54 pm

by jih

You rode one bike with a slammed stem, and one with a spacer stack. The slammed bike is going to be uncomfortable if you aren't used to a more aggressive position.

robeambro
Posts: 616
Joined: Sat Jul 07, 2018 6:21 pm

by robeambro

jih wrote:
Sat Nov 24, 2018 4:38 pm
You rode one bike with a slammed stem, and one with a spacer stack. The slammed bike is going to be uncomfortable if you aren't used to a more aggressive position.
No, the BMC has far less stack vs the Emonda (nearly 3cm less), so the Emonda is definitely not more aggressive even if partly slammed.

mattr
Posts: 4673
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

cro2 wrote:
Sat Nov 24, 2018 2:18 pm
This basically makes any further reasoning pointless.
You haven't yet provided any reasoning, just your beliefs.
cro2 wrote:
Sat Nov 24, 2018 2:18 pm
The choice is yours.
except it isn't, generally. As by the time you find out you're dealing with a charlatan or a formula following drone, you've already paid.
cro2 wrote:
Sat Nov 24, 2018 2:18 pm
mattr wrote:
Sat Nov 24, 2018 12:00 pm
I guess this is the issue with modern society, the default position is to throw money at any problem. Rather than throwing some rational thought and basic problem solving skills at it instead.
Your rationale is based on your beliefs, not actual studies or proofs.
and 25 years of dealing with people who increasingly throw money at problems to get it to go away.

zefs
Posts: 438
Joined: Sat Aug 05, 2017 8:40 pm

by zefs

Don't put everyone in the same basket, our bodies were not meant to be used for cycling and depending on each one's body and assymetries the more difficult it is to fit. If a fitter is not good at doing that, that doesn't mean bike fitting is a scam.

Pros have more power on their legs and can get away with different setups, for recreational cyclists it's as important to have a good fit to avoid injuries and enjoy cycling more in my opinion.

TobinHatesYou
Posts: 4367
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

robeambro wrote:
Sat Nov 24, 2018 3:10 pm

TeamMachine. 386mm reach, 550mm effective top tube, handlebar reach 77mm, and again, 110mm stem
Emonda. 387mm reach, 560mm effective top tube, handlebar reach (? maybe 93mm), 100 stem.

If the bar was a Bontrager VR-C (standard in on most Trek race bikes), the reach was a monstrous 100mm. When I switched to the XXX bar/stem combo from ENVE compacts, I had to go from a 130mm stem to a 110mm stem equivalent. I don’t know why Trek/Bontrager calls a 100mm reach bar a “compact” bar...it’s one of the longest bars I’ve ever owned.

robeambro
Posts: 616
Joined: Sat Jul 07, 2018 6:21 pm

by robeambro

TobinHatesYou wrote:
Sat Nov 24, 2018 11:59 pm
robeambro wrote:
Sat Nov 24, 2018 3:10 pm

TeamMachine. 386mm reach, 550mm effective top tube, handlebar reach 77mm, and again, 110mm stem
Emonda. 387mm reach, 560mm effective top tube, handlebar reach (? maybe 93mm), 100 stem.

If the bar was a Bontrager VR-C (standard in on most Trek race bikes), the reach was a monstrous 100mm. When I switched to the XXX bar/stem combo from ENVE compacts, I had to go from a 130mm stem to a 110mm stem equivalent. I don’t know why Trek/Bontrager calls a 100mm reach bar a “compact” bar...it’s one of the longest bars I’ve ever owned.
Whaat, that's nuts.
To be honest I had thought it could be this one: https://www.trekbikes.com/gb/en_GB/equi ... r/p/13294/

Nevertheless, that's huge. Enough to throw any bikefitting out of the window.

cyclenutnz
Posts: 801
Joined: Tue Jul 18, 2006 5:18 am
Location: Cambridge, New Zealand
Contact:

by cyclenutnz

robeambro wrote:
Sat Nov 24, 2018 3:10 pm
How would you guys go about comparing these two bikes?
Is it normal that I felt much better on the BMC, and why?
Is the effective top tube a meaningful metric anyway?
Top tube is of limited meaning unless you factor seat tube angle, which is why we look at reach
Reach is not that meaningful unless you normalise for stack.
10mm of stack is ~3mm impact on reach
robeambro.JPG
Which is why looking at bar XY, as above, is the better approach. Once you've normalised for Bar Y you see that the Emonda is actually 10mm longer.

Bar XY falls down if you're not using the same reach bars. For bikes with integrated bars I use Bar curve X and bar top Y, but that isn't in the frame comparison tool. So you just need to factor that difference separately and then look at Bar XY.

The standard Bontrager bars have an 85mm reach centre to centre, compared to 77mm for the BMC. Which shouldn't be enough for the difference you felt.

Which leaves saddle differences as the most likely suspect. Emonda saddle may have had you sitting oddly and thus loading up your back.

All in all, this serves to illustrate the risks of test riding. Unless both bikes are setup the same you just can't evaulate them properly.
http://www.speedtheory.co.nz
http://www.velogicfit.com - 3D Motion Capture and Frame Finder Software

robeambro
Posts: 616
Joined: Sat Jul 07, 2018 6:21 pm

by robeambro

cyclenutnz wrote:
Sun Nov 25, 2018 10:10 pm
robeambro wrote:
Sat Nov 24, 2018 3:10 pm
How would you guys go about comparing these two bikes?
Is it normal that I felt much better on the BMC, and why?
Is the effective top tube a meaningful metric anyway?
Top tube is of limited meaning unless you factor seat tube angle, which is why we look at reach
Reach is not that meaningful unless you normalise for stack.
10mm of stack is ~3mm impact on reach
robeambro.JPG

Which is why looking at bar XY, as above, is the better approach. Once you've normalised for Bar Y you see that the Emonda is actually 10mm longer.

Bar XY falls down if you're not using the same reach bars. For bikes with integrated bars I use Bar curve X and bar top Y, but that isn't in the frame comparison tool. So you just need to factor that difference separately and then look at Bar XY.

The standard Bontrager bars have an 85mm reach centre to centre, compared to 77mm for the BMC. Which shouldn't be enough for the difference you felt.

Which leaves saddle differences as the most likely suspect. Emonda saddle may have had you sitting oddly and thus loading up your back.

All in all, this serves to illustrate the risks of test riding. Unless both bikes are setup the same you just can't evaulate them properly.
Thanks! That is some really nice tool there!

Only a couple questions.

- you mentioned that, once normalised for Bar Y, the Emonda is 10mm longer. However, from the screenshot I can read that the Bar X measurements are 478mm and 477mm, so not quite 10mm. Or am I looking at the wrong figures?

- since I have your attention.. if I understand it correctly, if I have my vertical saddle height to BB, I can deduct Bar Y and obtain my saddle to bar drop? I thought this would be the case, but I get some flippin' crazy numbers. I mean, I don't think I had a 14cm saddle-to-bar drop.

moyboy
Posts: 447
Joined: Thu Aug 18, 2016 12:19 am

by moyboy

Just putting my 2 cents.

I had a few fits from bike shops but ended up going with a local independent fitter he explained why i had pains and also dialed in cleat wedges / insoles and focused on how flexible i was and biomechanics. (ie shorter cranks to minimize dead spots at the top from flexibility of hip joint).

Then he worked on Stem / how my elbow bow out on 42cm handlebars.
out of the fit i ended up with a more aero agressive position but more comfortable.
The good thing was there was a free fit 2 months after to tweak the original 4 hour fit.

I got a printout of all the measurements and now can go to town on knowing what WW parts i want without a shot in the dark on fit.

robeambro wrote:
Sat Nov 24, 2018 3:10 pm
Meanwhile, I'll try to bring my thread back to bikefitting :lol:

I tried both the the Emonda H2 56 (I think 2017 model, it was dark blue and had Ultegra mechanical and rim brakes) and the BMC TeamMachine SLR01 54. Admittedly, I tried the BMC only for some 15 minutes, while I had a 2h ride on the Emonda. The BMC had a 110mm stem and a bit of a spacer tower, while the Emonda had a 100mm stem and was moderately slammed. Given the larger stack on the Emonda, I would expect them to be around the same in terms of saddle to bar drop.

Now, as soon as I got onto the BMC, I felt it to be fine. I didn't feel too stretched, and seemed the right size for me. As soon as I got onto the Emonda, I instantly felt stretched, and ended my ride with a sore back and neck.

I came home, sure to find some big difference in reach / effective top tube / whatever.
What I see instead is,

TeamMachine. 386mm reach, 550mm effective top tube, handlebar reach 77mm, and again, 110mm stem
Emonda. 387mm reach, 560mm effective top tube, handlebar reach (? maybe 93mm), 100 stem.

Now, unfortunately I am not 100% sure on the handlebar reach for the Emonda. And I can't be sure the saddle setback was the same (my gut feeling is that I was slightly more far forward on the BMC).

If you ask me, I don't see a massive difference (even if, as a rough and meaningless metric, we check effective top tube + stem length + handlebar reach, the Emonda was around 15mm longer than the BMC, not an awful lot). I am now also reading that head tube angle affects the calculations, not sure exactly by how much.

How would you guys go about comparing these two bikes?
Is it normal that I felt much better on the BMC, and why?
Is the effective top tube a meaningful metric anyway?

cyclenutnz
Posts: 801
Joined: Tue Jul 18, 2006 5:18 am
Location: Cambridge, New Zealand
Contact:

by cyclenutnz

robeambro wrote:
Mon Nov 26, 2018 12:46 pm
- you mentioned that, once normalised for Bar Y, the Emonda is 10mm longer. However, from the screenshot I can read that the Bar X measurements are 478mm and 477mm, so not quite 10mm. Or am I looking at the wrong figures?
You'll see that I had to put a 10mm longer stem on the BMC to get the Bar X within 1mm. So that is compensating for the longer Emonda frame.
- since I have your attention.. if I understand it correctly, if I have my vertical saddle height to BB, I can deduct Bar Y and obtain my saddle to bar drop? I thought this would be the case, but I get some flippin' crazy numbers. I mean, I don't think I had a 14cm saddle-to-bar drop.
Bar Y is to the centre of the bar, so you need to correct for bar radius to get drop to the tops.
And vertical saddle height is different to measured saddle height. If you hadn't already - drag out pythagoras to get the actual vertical component from the BB.
For instance - a 780mm measured saddle height will be ~748mm vertical component
http://www.speedtheory.co.nz
http://www.velogicfit.com - 3D Motion Capture and Frame Finder Software

by Weenie


robeambro
Posts: 616
Joined: Sat Jul 07, 2018 6:21 pm

by robeambro

cyclenutnz wrote:
Tue Nov 27, 2018 3:14 am
robeambro wrote:
Mon Nov 26, 2018 12:46 pm
- you mentioned that, once normalised for Bar Y, the Emonda is 10mm longer. However, from the screenshot I can read that the Bar X measurements are 478mm and 477mm, so not quite 10mm. Or am I looking at the wrong figures?
You'll see that I had to put a 10mm longer stem on the BMC to get the Bar X within 1mm. So that is compensating for the longer Emonda frame.
- since I have your attention.. if I understand it correctly, if I have my vertical saddle height to BB, I can deduct Bar Y and obtain my saddle to bar drop? I thought this would be the case, but I get some flippin' crazy numbers. I mean, I don't think I had a 14cm saddle-to-bar drop.
Bar Y is to the centre of the bar, so you need to correct for bar radius to get drop to the tops.
And vertical saddle height is different to measured saddle height. If you hadn't already - drag out pythagoras to get the actual vertical component from the BB.
For instance - a 780mm measured saddle height will be ~748mm vertical component
Thanks, all clear! Would be cool if the online tool would also allow to calculate a theoretical saddle to bar drop :)

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