Bike fitting: why? Why not?

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Cyril Haearn
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Bike fitting: why? Why not?

Postby Cyril Haearn » 16 Feb 2020, 9:31pm

I read of someone who paid for several bike fittings, got a different result each time :?
Could all be right? Or all be wrong? Is it best to collect knowledge and do it oneself?
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peetee
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Re: Bike fitting: why? Why not?

Postby peetee » 16 Feb 2020, 10:50pm

There’s no straight answer to that. Everyone is built differently and their joints and muscles will find certain positions more tolerable than others. Throw the ageing process and injuries into the mix and the standard model of what is right becomes less and less relevant and the science starts to be replaced by the experienced eye.
Miguel Indurain was a Tour winner and could produce colossal amounts of leg power but his riding position flew in the face of conventional thinking for producing watts and being aerodynamic. He simply couldn’t ride with a flat back but his position was comfortable for him so he could turn out enough watts to overcome the drag and beat the competition to boot.
Last edited by peetee on 17 Feb 2020, 5:38pm, edited 1 time in total.
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drossall
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Re: Bike fitting: why? Why not?

Postby drossall » 16 Feb 2020, 11:34pm

For the same reason as you, I wonder whether it's really better than the traditional option of joining a club and letting the more experienced riders advise you.

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Re: Bike fitting: why? Why not?

Postby fullupandslowingdown » 17 Feb 2020, 12:26am

One of the US team docs that advised Lance A, used to say the most reliable way to size the bike, was to observe the rider when they're standing on the pedals to see what their minimum and maximum knee flexion was, and from that you could then fit the bike around the rider. What he termed as self selection.

But he also said that you can't be competitive if you eat a medium to high fat diet, in his opinion only a hi carb diet could provide the necessary fuel to keep a multistage athlete at peak endurance.

Ballantine said that you would often get two different results if you went to two different frame builders, as the traditional builder would over time develop their own interpretation of theory and practice. I suppose that this is where the WATT Bike and similar come into play. Set them up and then independent of variations in wind and gradient and traffic etc, you can see what position gives you the most watts, if that's what you are after, or with a HRM, what gives the most watts for the least effort as suggested by your heart rate. Or just ride and see if it feels right after a hundred miles.

And lastly as said, if you have any degenerative wear or non standard limbs, a bike fit might not work anyway if it makes you use your limbs in an awkward way, I'd suspect only the most experienced fitters would be good at correcting for that, if someone sets up shop with say a sports degree and an interest in sports medicine, that doesn't mean they will be any good, in the same way that a doctor after 5 years med school has to learn real medicine in actual practice. Thats my 3/6 on it. used to be only 2/- but inflation you know.

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Cunobelin
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Re: Bike fitting: why? Why not?

Postby Cunobelin » 17 Feb 2020, 6:03am

Some years ago, my wife and I treated ourselves to ~gorn Raven bicycles

We went down to try and discuss

My wife had been riding and touring for ten years, but as soon as they saw her bike they stated it was far too big and gave her a much smaller one. After half an hour her scepticism vanished and she found the smaller bike far more comfortable, nimble and manageable - that is what we bought

Without that she would have carried on riding bikes that were manageable, but not the best for her

drossall
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Re: Bike fitting: why? Why not?

Postby drossall » 17 Feb 2020, 8:20am

But was that a modern bike fit, or a traditional experienced eye? Sounds like the latter.

alexnharvey
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Re: Bike fitting: why? Why not?

Postby alexnharvey » 17 Feb 2020, 9:06am

Cyril Haearn wrote:I read of someone who paid for several bike fittings, got a different result each time :?
Could all be right? Or all be wrong? Is it best to collect knowledge and do it oneself?


It would be interesting to see the original article or post that compared several bike fit methods.

Cyril Haearn
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Re: Bike fitting: why? Why not?

Postby Cyril Haearn » 17 Feb 2020, 9:27am

alexnharvey wrote:
Cyril Haearn wrote:I read of someone who paid for several bike fittings, got a different result each time :?
Could all be right? Or all be wrong? Is it best to collect knowledge and do it oneself?


It would be interesting to see the original article or post that compared several bike fit methods.

It was somewhere on these fora I think, you could probably find it
Nice one Cyrille, nice one son..
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mig
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Re: Bike fitting: why? Why not?

Postby mig » 17 Feb 2020, 9:44am

fitting for what end purpose though? a fitting to produce a bike for racing (TT even) would give a different result than if you asked for a bike you could ride loaded all day.

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Audax67
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Re: Bike fitting: why? Why not?

Postby Audax67 » 17 Feb 2020, 10:25am

I had a quick bikeshop fit in 2002 or thereabouts, and later bought a Ti frame that roughly corresponded to my measurements and built my main bike around it. I rode that bike until 2015, doing several SR series, a couple of PBPs and sundry other 1000k rides. My rationale was "if I can do that on it then the fit must be good", and if I did have tendinitis in one hip after the longer rides it was just anno domini and luck. Others suffered more.

In 2015 I bought a new Trek. The dealer offers Retül laser/video bike fitting as a service (pricey), but he threw in a buckshee 1-hour measurement session before ordering and a 2-hour bike fit once it arrived. I ended up with a bike that most noticeably is around 2 cm shorter that the Ti, and is incredibly comfortable in general. I haven't had tendinitis since.

Moral: plenty of places offer cheap measurement services that are nothing but window-dressing. If you can find somewhere that offers a serious service it'll cost you real money, but it's well worth it.

Beware helpful bike shops afterwards, though. A chum had a pricey fit then later had his bike serviced by a different shop, where the obliging mechanic realigned everything "correctly".
Have we got time for another cuppa?

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NUKe
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Re: Bike fitting: why? Why not?

Postby NUKe » 17 Feb 2020, 4:30pm

There are bike fits and there are bike fits.
And most people only need a very basic fit. Something you do yourself by trial and error or get a knowledgeable friend to help. Any bike shop worth its salt should do this at the time of buying. A more detailed fit is really only worth it if you are trying to set a bike up for racing, TT or triathlon OR if you have a particular need due injury or skeletal muscular alignment. A good bike fitter will listen to your needs, probe you about real time use. Measure and understand your flexation and aligment. A good bike fitter will also follow up and fix any problems
People always forget that fit can change over time as well, either through age or injury.
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fredwinter
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Re: Bike fitting: why? Why not?

Postby fredwinter » 17 Feb 2020, 6:42pm

I read of someone............. Just a bit bored were you!

drossall
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Re: Bike fitting: why? Why not?

Postby drossall » 17 Feb 2020, 8:27pm

alexnharvey wrote:It would be interesting to see the original article or post that compared several bike fit methods.

There was one in the comic a few years back that produced the same conclusion - different results from different bike fits.

Cyril Haearn
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Re: Bike fitting: why? Why not?

Postby Cyril Haearn » 17 Feb 2020, 8:53pm

The comic, or Cycling Weakly :wink:

I think this is one case where one should try to do it oneself (not pay an expert), as described by 531Colin
The case described above, where a well-meaning LBS person changed the adjustments, is a bit disturbing
Nice one Cyrille, nice one son..
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We love safety cameras, we love life "1330"

PaulS
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Re: Bike fitting: why? Why not?

Postby PaulS » 18 Feb 2020, 9:41am

Last year I had a bit of time so decided to treat myself to a bike fit. Called in to Hewitts on the way to a trip round the Lake District. I've been riding for years, read loads of stuff in books and on-line, listened to mates' advice. Expected a minor tweak here and there. First thing he did was put my seat up 32mm. Haha. What the hell do I know?! A few more adjustments and replacements. Bike feels great, I feel great. Best hundred quid I've spent for a long time.