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Bike-Fit Question

Hello !!

I have yet to undergo a Bike-Fit and am considering one even though I will not have access to the more advanced versions of it, ie computerized etc. ( Perhaps the advance version is not even required ? ) 

I remain hesitant for I don't know how well informed/experienced Bike-Shop Staff are where I reside regarding "all things Bike-Fit". ( State this based on my initial interactions with the staff from two Bike-Shops ). 

None-the-less, my question : 
How does one translate the findings of a Bike-Fit to a bike of ones choice ? This becomes a bit challenging as the Brand of the bike I plan on purchasing is not represented in India and will have to be imported.

To arrive at some understanding, I plan on test-riding bikes from a competing Brand/s and will then need to extrapolate from there on in. It is this translation I refer to as each Brand and each of their Models will maintain different geometries.

At this point, my aim is to make sure I order a bike with the correct Crank Length, Stem Length, Handlebar Width and of course the Frame Size.

I believe if I get the above right, the other main variables of positioning of the saddle ( fore-aft and height ), arriving at the correct number of Spacers under the Handlebar and Shoe-Cleat position will be easier achieved.

Any thoughts on how I can achieve this translation ?

Thanks in advance,

Jai

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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17 comments

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matthewn5 | 3 years ago
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I'd be very skeptical of having a bike fit in your circumstances. They're very expensive and as several people have noted, don't necessarily make you feel more comfortable on the bike.
After a bad experience buying a frame recommended by a bike shop that was just too big, so I could never get a comfortable position, I used an online bike fit calculator (now archived) and it worked well, giving a range of fits depending on your style, rather than a single 'perfect' solution. This one is ok too:
https://www.jensonusa.com/bike-fit-calculator
This gave me the basics, and I got a frame that was the right size, and played around with stem length and crank length until it felt perfect. Since that experience I am confident in picking bikes without testing them, because I know the stack and reach and top tube length that suits me. It has worked brilliantly ever since and every bike I've had since then has fitted like a glove. I'd recommend taking the time to measure yourself and get a 'ball park' figure, then try riding a bike in the recommended size and see how it feels. No amount of 'ideal' sizes produced by so-called 'expert' bike fitters beats your own experience of riding a bike, which you can extrapolate to others.

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jacknorell | 3 years ago
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Go read Steve Hogg's articles on bike fitting. Also look up Bike Fit James in Instagram for good insight

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Recoveryride | 3 years ago
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Armed with your height, inseam and a few other measurements, you should be able to get (or get the company to recommend) the right size frame fairly easily. After that, the old not-quite-straight leg test should get you +/- 1cm for saddle height, then front hub obscured by bars when on the hoods should get you in the ballpark for reach. People now argue about knee over pedal spindle but unless you know it doesn't work for you I'd use that to start. Those pretty basic things should get you 95%+ of the way there and I'd say at worst you won't have a bad fit.

From there, put the miles in and if something feels a bit off, make small adjustments 1 by 1, and keep notes. That's how I've done it for twenty years. I got a complementary bike fit with my last purchase and the fitter recommended 170mm cranks rather than the 172.5s the bike came with. Otherwise, he didn't change a thing.

The only time I'd pay for a full-on fit is for TTing, where the aero side of it is massive and small changes can have massive effects on the outcome.

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David9694 | 3 years ago
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maybe you're over-thinking the whole bike fit thing? not sure how much riding you're doing now, but you probably want to do some riding in on a bike you're broadly comfortable on before have a bike fit. I've had one, because I was getting all sorts of aches and pains I wanted to make sure I wasn't doing anything wrong, fit wise. 

there doesn't seems to be a hard and fast rule about crank length, just a slight inclination for longer legs, longer cranks.

Saddle height, you want your knee just off straight at 5, 6 or 7 o'clock. As I've got fitter, I've "grown" at least 1.5"!

Handlebar positioning vertical and horizontal I think is the greatest variable - you just want to be able to sit on the bike and your hands fall naturally on the brake hoods without you feeling compressed or more likely, stretched.  

Start with bars and saddle dead level. You can turn the bars down a bit if you want and twiddle with the location of the hoods too. 

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flyingpitman | 3 years ago
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Hi Jai,I have the Phil Burt book "Bike Fit" and found that invaluable.It covers everything you need to know,and also covers what to do if a problem occurs.A really good book,and one you can go back to time and time again if you need too.

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bobrayner | 3 years ago
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I've had a couple of bike fits in recent years.

One was a very geek-oriented system, which suited me fine; they just took lots of measurements (shoulders, legs, &c), and used those to calculate other measurements (like crank length and top tube), and gave me a printout of both sets of numbers. That approach definitely worked better in the old days when more bikes were custom built or, at least, available in 2cm increments of frame size.

The other was ostensibly more about fitting a particular bike brand, so it started with the same measurements but those would be fitted to, say, a size medium bike from brand X. Except that the fitter never actually gave me the details and doesn't reply to emails, so I paid for somebody to measure me but not actually provide any of the data.

If you can get either kind of fit, it should be possible to translate that into the proper size of a bike from any brand as long as there's published data on the geometry, although you might have to fine-tune later. Stem and spacers and cleats are definitely a good place to focus on fine-tuning (without having to buy a completely new bike) - sometimes a position that feels comfortable in the shop can make your back hurt after 2 hours on the road!

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Secret_squirrel | 3 years ago
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Its quite simple to take a bike fit from one bike to another assuming they are of roughly the same geometry.   You line the second bike up by eye by putting them next to each other.

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Chris Hayes | 3 years ago
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I had one bike fit: rig, angle measurements, sensors, beeps - then I made the same adjustments to my other bikes.  Can't say that I was impressed and I reversed the changes a few less than comfortable rides later.  I was charged a not inconsiderable sum for someone to lower my seat a bit.  

My advice would be to set your bike up so that it's comfortable to ride - and ride it.  I'd pay more attention to your cleats as this could cause knee damage. But if it helps the correct number of spacers under your handlebars is zero  1

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j_vora replied to Chris Hayes | 3 years ago
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Chris Hayes wrote:

I had one bike fit: rig, angle measurements, sensors, beeps - then I made the same adjustments to my other bikes.  Can't say that I was impressed and I reversed the changes a few less than comfortable rides later.  I was charged a not inconsiderable sum for someone to lower my seat a bit.  

My advice would be to set your bike up so that it's comfortable to ride - and ride it.  I'd pay more attention to your cleats as this could cause knee damage. But if it helps the correct number of spacers under your handlebars is zero  1

Agree about setting the cleats in ways to avoid injury - 
Why do you suggest no spacers under the bar ? Is that because the frame itslef would be of a size that "fits you" ?

Thanks for your inpits !

Jai

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Secret_squirrel replied to j_vora | 3 years ago
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The spacers bit was a joke.... 

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pablo | 3 years ago
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Ah bike fiting is a complete can of worms.  The trueth is most of the 'science' is questionable at best. I've had 2 and been pretty happy with them as i did the research on who was doing it.  Go by reputation not system actaully stay away from systems.  Most fiters should use a jig and will give you the dimensions after and also transfer them to your bike and then put you on a turbo to make sure they still make sense.  For additional bikes they will obviously charge more.  If you are having problems after the fit go back to them they should fix the issue FOC.  

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j_vora replied to pablo | 3 years ago
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Hi Pablo :

Bike-Fit, a can of worms it is !!

And the fact that I am unsure about the "bBke-Fitters" where I reside makes the can and worms larger !! 

cool

 Thus I try to read up on it  and seek advice based on rider's experiences, such as yourself.

Thanks !


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Welsh boy | 3 years ago
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I am cynical about bike fit services, if there was one correct fit then every bike fitter would come out with the same position but that doesnt seem to be the case.  Before you part with your hard saved cash, ask yourself why you feel confident that the bike fitter you choose will be the one who comes up with the correct fir for you.  A quick look at some of the top riders will show that there isnt a perfect position on a bike, for example Thibaut Pinot alwas looks like he is riding someone (with shorter legs) elses bike and Sean Kelly (7 times winner of the Paris-Niece, Vuelta, multiple winner of classics) always looked like his stem was too short.

Do you ride with a club?  If so have a look at how the best riders in the club look on their bike and aim for something close to that, if not have a look at the pictures of good riders or get on the internet and look for look for bike fit info and go for something close to that as a starting point.  Remember, you can move your saddle up, down, forwards and backwards free of charge; you can change your stem length for about £8; you can change your handlebar height free of charge; you can alter the position of your foot on the pedal free of charge.  I would think long and hard about giving money to someone to tell you how to sit on your bike.

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j_vora replied to Welsh boy | 3 years ago
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Hello Welsh boy :

Main idea behind taking the bike-fit route is that as the brand of bike I would like to purchase is not available for me to test-ride where I reside, I am hoping a bike-fit and test-riding a different bike of "similar" geometry will enable me to select the correct components so as to arrive at an optimal fit.

Thanks,

Jai

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mtbtomo | 3 years ago
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The bike fit should give you dimensions from fixed points on the bike. The one I had, I got a diagram which measured horizontal saddle position in relation to the rear wheel axle. BB/cranks also. Distance from saddle to bars. Saddle height to BB centre. Etc. You should be able to mark these up on the geometry drawing of the bike (and size) of your choice. What are you technical drawing skills like?

Do you really mean a proper bike fit or are you just trying to find the right size bike? Any decent bike shop should be able to advise on the correct size and you could compare the geometry tables between different brands. A few millimetres difference here can be compensated by saddle position or a slightly shorter/longer stem etc.

Having bought the bike, you could then have a bike fit to optimise your fit if something doesn't feel just quite right. But it shouldn't be so wildly out, because the shop should have helped with the right frame size to begin with.

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j_vora replied to mtbtomo | 3 years ago
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Hello mtbtomo : 

Arriving at a correct Bike Size is something I am confident of achieving  - Its optimizing the bike by selecting the correct components is what I wish to "nail".

What is making the task challenging is that I will not be able to test-ride the model of the bike I wish to purchase as the choices available are limited.

So the idea is to test-ride bike of another brand and in the event it it "fits me", translate its measurements as closely as possible to the bike I will purchase through selecting the correct size of components to arrive at am optimal fit.

Your suggestion employing technical drawings is possible - Not on CAD, but on an application such as Adobe Illustrator - Good suggestion.

 Thanks !

 

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joeegg replied to j_vora | 3 years ago
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If I remember rightly a bike journal had a bike fit from 5 different companies. None of the fits matched each other. A friend had a bike fit as it was included with the new bike. The new position gave him severe back pain so he put it back to original. If you are already riding a bike that seems comfortable just take the measurements off that and compare to your prospective purchase.

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