Is Retul 3D Motion Capture worth it for bike fitting?

Discuss light weight issues concerning road bikes & parts.
TobinHatesYou
Posts: 1212
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

RussellS wrote:
Wed May 23, 2018 1:52 am
Concerning the Retul fitting system. My brother had the Retul fitting done recently. It produced odd results as far as I am concerned. He ended up being recommended a very small bike frame with very upright and short position. Short upright stem. It seemed to only look at his leg length only to determine frame size and completely ignored his torso length. He has short legs and long torso, so he really needs a frame with no standover at all and a long reach to the bars. I don't know if the Retul thing recommended this by itself, or the fitter entered various numbers to force the Retul to recommend this. So I'm not sure any official fitting system is worth anything. Its all up to the fitter. I can "fit" on a 50cm frame and a 64cm frame. Neither is the right size though.

Retul and BG have suggested ranges for just about all dynamic angles, including back position and arm bend. It's pretty hard for the system to spit out a fit that looks wrong without intervention from the fitter or the person being fitted. I imagine there are shops out there with Retul equipment but people who aren't at all trained to use them.

leandrofresh
Posts: 30
Joined: Mon Jul 13, 2015 12:45 am

by leandrofresh

RussellS wrote:
Wed May 23, 2018 1:52 am
Concerning the Retul fitting system. My brother had the Retul fitting done recently. It produced odd results as far as I am concerned. He ended up being recommended a very small bike frame with very upright and short position. Short upright stem. It seemed to only look at his leg length only to determine frame size and completely ignored his torso length. He has short legs and long torso, so he really needs a frame with no standover at all and a long reach to the bars. I don't know if the Retul thing recommended this by itself, or the fitter entered various numbers to force the Retul to recommend this. So I'm not sure any official fitting system is worth anything. Its all up to the fitter. I can "fit" on a 50cm frame and a 64cm frame. Neither is the right size though.
What you are describing is Retul trend. Short, upright, slammed saddle to the front. Instead of working on cyclist flaws, flexibility and reeducation, they just give you a crappy solution. That kind of fitting actually makes you weaker, sometimes when they see a lot of spinal flex in a cyclist, they just do upward and short instead of trying to educate the cyclist to roll from the hips with a flat spine.

I would like to see your brother in the bike. If he has short legs, long torso everything suggest that he should be riding with a longer reach but with the correct use of his body.

RussellS
Posts: 724
Joined: Wed Feb 03, 2010 1:31 am

by RussellS

TobinHatesYou wrote:
Wed May 23, 2018 2:30 am
It's pretty hard for the system to spit out a fit that looks wrong without intervention from the fitter or the person being fitted. I imagine there are shops out there with Retul equipment but people who aren't at all trained to use them.
I am guessing his Retul fitting recommendation is due to the fitter's preconceived notions. Brother mentioned the fitter commented on how stretched out my brother is on his old bike and recommended a very short, upright, chest in the wind position for old folks on the new bike. Due to a childhood accident, my brother has the torso of someone who is 5'10" and the leg length of someone who is 5'4". Roughly. He has a late 1980s or early 1990s Trek 5200 50cm frame with 13 or 14cm quill stem, saddle back, hoods at the very end/curves of the bars.

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

by TobinHatesYou

Not sure what you mean. Short legs means less setback (vs BB-c,) not more. Unless he prefers an even lower saddle height than typical for someone with his inseam, his saddle position at the rails should be pretty standard.

audiojan
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Joined: Fri Jan 27, 2006 1:38 pm
Location: New Hampshire

by audiojan

Retul is nothing but a tool, albeit a pretty fantastic one. Don't think too much about what tool being used for the fitting, shop for the right fitter instead. A great tool in the wrong hands will yield poor result. A great fitter with a descent tool can still yield a great fit
"Suddenly the thought struck me; my floor is someone elses ceiling" - Nils Ferlin

uraqt
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Joined: Mon Apr 03, 2006 8:53 am

by uraqt

Everyone is missing the forest with bike fitting... it' not in the real world .... you are bettery off buying the software and then getting your riding buddies to film you with an phone.... everything is perfect two/three hours on a flat trainer ... nothing is perfect hour 5 @ 13%....


C

TobinHatesYou
Posts: 1212
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

uraqt wrote:
Sat May 26, 2018 2:15 am
Everyone is missing the forest with bike fitting... it' not in the real world .... you are bettery off buying the software and then getting your riding buddies to film you with an phone.... everything is perfect two/three hours on a flat trainer ... nothing is perfect hour 5 @ 13%....


C

Every five hour ride includes the first 2-3 hours. Not every ride is >2-3 hours...most aren't. Also spending the first half of a long ride in comfort unsurprisingly benefits me in hour five. I'm not sure what you're trying to get at. Also trainers are most uncomfortable.

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silvalis
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Location: Aus

by silvalis

And any fitter worth their salt provides followup services...

mdeth1313
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Location: Dutchess County, NY

by mdeth1313

Over 10 years ago I went for a retul fitting. Big mistake. Their fee structure was the same, except it was 200 w/out and 300 w/ retul. Bottom line - the fitter sucked. It was a big mistake. I used a different fitter 3 or 4 years later who was much better- no retul. That one helped me find a better position for my body (as opposed to the first idiot who tried to set me up like I was racing). BUT, the leg length descrepancy he found and "fixed" with a shim and cleat adjustment turned out to be functional, not structural and made things (temporarily worse). Turns out almost all of my issues were related to lack of flexibility, lack of core strength and 2 rounds of phys therapy (and an excercise/stretching regimen) fixed everything.

I'd rather spend the money on different size/length components and figure it out myself.
Speedplay is the devil!

uraqt
Posts: 816
Joined: Mon Apr 03, 2006 8:53 am

by uraqt

@TobinHatesYou

I know fitting happen in labs (not real riding conditions) and they don't translate to real riding... too many variables on any ride no matter how short or long. You can get any perfect posistion the fitter wants in on trainer, for two or three hours easy... However when you are tired everything goes to shit, or on that big climb or sprint for the line...

C

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

by TobinHatesYou

uraqt wrote:
Mon May 28, 2018 1:58 am
@TobinHatesYou

I know fitting happen in labs (not real riding conditions) and they don't translate to real riding... too many variables on any ride no matter how short or long. You can get any perfect posistion the fitter wants in on trainer, for two or three hours easy... However when you are tired everything goes to shit, or on that big climb or sprint for the line...

C

I still fail to see how this is relevant. If you're tired and fatigued, you're tired and fatigued. If you're suggesting people get fit so they are somehow less comfortable on 2-3 hour rides, but more comfortable on 5 hour rides, that's not really a thing. No fitter defaults to putting customers in slammed positions unless there is mutual understanding. If a cyclist mostly rides 2-3 hours at a time, he should be fit accordingly.

RussellS
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Joined: Wed Feb 03, 2010 1:31 am

by RussellS

TobinHatesYou wrote:
Mon May 28, 2018 5:02 am
uraqt wrote:
Mon May 28, 2018 1:58 am
@TobinHatesYou

I know fitting happen in labs (not real riding conditions) and they don't translate to real riding... too many variables on any ride no matter how short or long. You can get any perfect posistion the fitter wants in on trainer, for two or three hours easy... However when you are tired everything goes to shit, or on that big climb or sprint for the line...

C

I still fail to see how this is relevant. If you're tired and fatigued, you're tired and fatigued. If you're suggesting people get fit so they are somehow less comfortable on 2-3 hour rides, but more comfortable on 5 hour rides, that's not really a thing. No fitter defaults to putting customers in slammed positions unless there is mutual understanding. If a cyclist mostly rides 2-3 hours at a time, he should be fit accordingly.
Kind of agree. Not sure how being tired and fatigued affects anything. I use the exact same positions on my bike whether its the first minutes or the last hour of an eight hour ride. I always ride with my hands on the hoods, tops, or drops. Fresh or fatigued. My saddle setback and height stay the exact same whether I am fresh or fatigued. My reach to the bars is the same too. How I fit the bike never changes. What's being suggested here is about like saying you need a different shoe size or helmet size depending on whether you are fresh or fatigued. About the only change I ever experience is when I am super tired, I will likely ride on the tops more than when fresh. Tops are an easy not push hard position. Which works well if I am tired. But I also ride the hoods when tired. And their position does not change. I suppose some people may not pedal as fluidly when tired. But not sure that affects anything because the crank arms are solid objects fixed to a spindle. They only go round in perfect circles. So no matter how good or bad you pedal, they always go around in perfect circles.

leandrofresh
Posts: 30
Joined: Mon Jul 13, 2015 12:45 am

by leandrofresh

uraqt wrote:
Sat May 26, 2018 2:15 am
Everyone is missing the forest with bike fitting... it' not in the real world .... you are bettery off buying the software and then getting your riding buddies to film you with an phone.... everything is perfect two/three hours on a flat trainer ... nothing is perfect hour 5 @ 13%....


C

Not true. Weather you are 15min on a trainer or 5h on the road. Your body and how it interacts with the bike doesn't change. You have a certain antropometry and the bike is fitted according to your body, legs, arms, flexibility within your optimal and safe brackets. You shouldn't be experiencing any discomfort after 5 hours besides, being tired.

You are missing the point. It's adequating your body to the bike, and the technique of course. If after 5hours you experience pain in a certain area of your legs there are two options. You are tired and you forced yourself riding over your possibilities. Or you have been pedalling with the wrong technique. Every modern bikefit should be addressed to teach proper technique to the cyclist too. There are of course discomfort which can be material related, like shoes for example, which is the most common cause of discomfort.

Fiery
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Joined: Sat Mar 16, 2013 9:21 am

by Fiery

Your body and how it interacts with the bike can change a lot during a long, hard ride. Posture and technique can change as muscles get tired. Back slouches, shoulders shrug, elbows lock out, pelvis rolls, hamstrings tighten, heels drop... What looked and functioned perfectly fine for an hour or two can fall apart after five hours. A good fitter should be able anticipate and adapt for somehting like this, but we can't pretend it doesn't happen at all. I mean, I've read articles by fitters where they described encountering problems like this. (Not only that, I've seen accomplished fitters complain that what looked fine on a trainer can fall apart as soon as the rider hits an actual road, even before they get tired.)

leandrofresh
Posts: 30
Joined: Mon Jul 13, 2015 12:45 am

by leandrofresh

Fiery wrote:
Tue May 29, 2018 12:44 pm
Your body and how it interacts with the bike can change a lot during a long, hard ride. Posture and technique can change as muscles get tired. Back slouches, shoulders shrug, elbows lock out, pelvis rolls, hamstrings tighten, heels drop... What looked and functioned perfectly fine for an hour or two can fall apart after five hours. A good fitter should be able anticipate and adapt for somehting like this, but we can't pretend it doesn't happen at all. I mean, I've read articles by fitters where they described encountering problems like this. (Not only that, I've seen accomplished fitters complain that what looked fine on a trainer can fall apart as soon as the rider hits an actual road, even before they get tired.)
Fitters are fitters, not magicians. The same issue happens in running for example, of course some things will fall apart when you start to get tired. What people should do is train in order to avoid that, or don't force themselves to pedal the wrong way for five hours. The fitter you are, and the smoother your technique, the later the issues will appear. I assure you that the bike fit they do to you in the rollers is perfectly fine. I follow a training plan with lots of days with 5-6 hours and double sessions and I end up tired, but not with pain or injury. But of course, a fitter puts you in the best position possible to avoid that. The first question a fitter has to do, is: Are you training for racing? Fun? Hours on the saddle?

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