Bike fitter mistake, or am I weird?

littledove44

Having read a recent thread I was led to the Lemond bike fitting chart.
http://myworldfromabicycle.blogspot.co. ... chart.html

With an 80cm inside leg (measured several times) my saddle height should be 70.6 or 69.9 (87.2-17.25)

Despite this, my BG fit has my saddle set at 74, with a leg angle of 35 degrees.

4cm is a big difference. I am told my hips do not rock when I pedal, but it would be a shame to be losing a lot of power if that is the case.

Anyone with bike fit experience who can explain what might be going on?

I am quite happy to drop the saddle down, but it will of course feel very weird and I am not sure whether I am good enough to be able to tell if it is more powerful. I have done several thousand miles with this position and no injury issues, so don't want to change it for no reason at all.

ugo.santalucia

I use the Lemond method... 109% (or it's 108 can't remember) of your inseam between the top of the saddle and the pedal axle when the crank is in line with the seat tube and the pedal is low down. It works out at 93-94 cm for me and it's spot on.
There are a million methods and fits and Lemond's might not work for all, but he was one of the guys with the best position on the saddle, so it's not a bad start. If you're built weird it won't definitely work for you.
This is how it looks for me

sloppyschleckonds

Think I'd want optimum fit for power output though….which the OP may not be getting.

littledove44

SloppySchleckonds wrote:

Think I'd want optimum fit for power output though….which the OP may not be getting.

That's my problem.

I originally set the saddle at 109%. Felt fine to me, but what do I know?

The fitter put it up several cm. felt weird, but I have got used to it, and I am stronger than I was when the fitting was done.

I am happy to put the effort in to get used to anything. I just want it in the best place for power. But, if I drop it then surely my knee angle will increase over the 35% it is now and I have read that 35% is the max that a road bike should be.

Perhaps I need to pay another bike fitter with more expertise.

JayKosta

It also depends on whether you keep your foot level towards the bottom of the stroke, or if you lower your toes. Some people are best with keeping their foot level, and others using up/down tilt.
If it feels like you actually have to 'reach' for the pedal at the bottom of the stroke, then try riding with the saddle lowered a bit and see how that feels.

Jay Kosta
Endwell NY USA

dw300

It also depends on how big your feet are.

On average, the majority of people are not average.

styxd

My saddle is about 9cm higher than the 109% method. Don't know what my leg angle is, less than 35 degree's I'd have thought. I think if my saddle was 9cm lower, I'd struggle to turn the pedals over.

ugo.santalucia

If you are happy with Lemond's method, why do you need to throw away money for another bike fit? Some of these people are charlatans anyway... these fitting outfits are popping up like... like poppies really. There might be some really good ones, but if you are happy, you don't need one, clearly. It's a bit like going to see a physio for your knees if you don't have a knee problem...

zx6man

I set mine just by it being comfy, but just checked. 92cm form saddle to axle. My inseem is 84.5cm working
Lemond way 109% of my 84.5 is 92.1 , close enough for me :-)

littledove44

ugo.santalucia wrote:

If you are happy with Lemond's method, why do you need to throw away money for another bike fit? Some of these people are charlatans anyway... these fitting outfits are popping up like... like poppies really. There might be some really good ones, but if you are happy, you don't need one, clearly. It's a bit like going to see a physio for your knees if you don't have a knee problem...

The point is that I am NOT happy with the Lemond method. As I said, my saddle is 4cm higher than the Lemond method recommends.My BG fit was last year.

In summary.
Bike bought least year. Set it up with the 109 % at 70cm BB to saddle top. Seems ok to me, but what do I know.
BG fit shortly thereafter changed it to 74cm. Seemed weird but I got used to it.

I just want the most powerful position that I can live with for rides up to six hours.
I was wondering whether it was very unusual to be that different from the Lemond sizing? If so, then perhaps the BG guy got it wrong. He said my leg angle was 35 degrees. Most people seem to be less, but if I lower the saddle my angle is even more.
I am not an unusual shape (allegedly).

ugo.santalucia

Something must be wrong somewhere... maybe you failed to measure your inseam properly. Measuring inseams is not particularly easy. Maybe your testies are hanging loose and that's what you measured... I suggest taping them to your thigh and measuring again. To give you an idea, I am on the 109% method and if I rise the saddle by 4 cm, I can't even get on the damn bike, let alone pedal. The angle would be close to zero and I would destroy my knees in no time.

zx6man

Set it up with the 109 % at 70cm BB to saddle top. That isnt right, should be set to pedal axle.

littledove44

zx6man wrote:

Set it up with the 109 % at 70cm BB to saddle top. That isnt right, should be set to pedal axle.

That's what I did. Inseam 80. 109% is 87.2. Crank is 17.25, so BB to saddle top per LeMond would be 70.
Mine is 74.

littledove44

ugo.santalucia wrote:

Something must be wrong somewhere... maybe you failed to measure your inseam properly. Measuring inseams is not particularly easy. Maybe your testies are hanging loose and that's what you measured... I suggest taping them to your thigh and measuring again. To give you an idea, I am on the 109% method and if I rise the saddle by 4 cm, I can't even get on the damn bike, let alone pedal. The angle would be close to zero and I would destroy my knees in no time.

Clearly you have identified the problem.
I have managed to get a measurement inseam of 84. As this is a public forum I shall not explain the method. :shock:

So I am perfect with both BG and Lemond.

Thanks all. Just got to work out how to stop the gaffer tape from chafing now.

ugo.santalucia

littledove44 wrote:

Clearly you have identified the problem.
I have managed to get a measurement inseam of 84. As this is a public forum I shall not explain the method. :shock:

So I am perfect with both BG and Lemond.

Thanks all. Just got to work out how to stop the gaffer tape from chafing now.

... and once again it's been proved that gaffer tape solves most problems.

top_bhoy

I wasn't 100% sure myself of the correct reference points so I googled and found this:

http://myworldfromabicycle.blogspot.com.au/2010/05/lemonds-sizing-chart.html

Are sizing methodologies being confused?

The 109% uses the Hamley Sizing Method when the pedal in the down position along the angle of the seat tube. Theres not much of a difference between the methods but enough and if you use the incorrect reference point ie BB and not the pedal axle, everything is thrown well out.

styxd

I'm not sure why you're desperate to use some formula to work out your saddle height. These formulas do not take into account your pedalling style (toes down, heels down) your saddle setback, your saddle width, the thickness of the soles of your shoes, your pedal stack height, your sock thickness etc. etc.

littledove44

ugo.santalucia wrote:

littledove44 wrote:

Clearly you have identified the problem.
I have managed to get a measurement inseam of 84. As this is a public forum I shall not explain the method. :shock:

So I am perfect with both BG and Lemond.

Thanks all. Just got to work out how to stop the gaffer tape from chafing now.

... and once again it's been proved that gaffer tape solves most problems.

If it moves and it shouldn't-gaffer tape.
If it doesn't move and it should- WD40.

ugo.santalucia

The formula is a good starting point... it's like 5 a day or keep your cholesterol under 5.2, it works well for many. Most normally built people will fall into a + or - 1 cm from the 109% formula. Those small adjustments can be done at a later stage. Don't forget there are lots of folks out there who ride over 5 cm away from their ideal, which is the reason of this Bike-Fit nonsense. A day out with the club and you can head count those with a stem higher than the saddle... are they all freaks of nature or they need help with their position?

kajjal

littledove44 wrote:

ugo.santalucia wrote:

littledove44 wrote:

Clearly you have identified the problem.
I have managed to get a measurement inseam of 84. As this is a public forum I shall not explain the method. :shock:

So I am perfect with both BG and Lemond.

Thanks all. Just got to work out how to stop the gaffer tape from chafing now.

... and once again it's been proved that gaffer tape solves most problems.

If it moves and it shouldn't-gaffer tape.
If it doesn't move and it should- WD40.

No wonder people worry about middle aged road bikers

Garry H

littledove44 wrote:

ugo.santalucia wrote:

littledove44 wrote:

Clearly you have identified the problem.
I have managed to get a measurement inseam of 84. As this is a public forum I shall not explain the method. :shock:

So I am perfect with both BG and Lemond.

Thanks all. Just got to work out how to stop the gaffer tape from chafing now.

... and once again it's been proved that gaffer tape solves most problems.

If it moves and it shouldn't-gaffer tape.
If it doesn't move and it should- WD40.

Almost right;if it doesn't move and it should-hammer

bahzob

Do your legs move while cycling?

If not then measuring your inside leg might be handy way to fit your bike.

If they do then this method is not going to be anywhere near as good as a fitting that takes account of how your legs move and takes account of the many variables resulting from genetics and a lifetime's bumps and bruises.

A good bike fit that assesses you while riding your bike might cost a couple of hundred quid. While that sounds a lot it will most likely pay for itself in terms of saving on stuff not suited for you and, quite possibly, mean riding in more comfort.

If performance is your goal then its a no brainer a good bike fit will most likely bring end on up with you being faster on a bottom of the range alu bike vs badly fitted top of the range carbon fibre aero speed machine.

ollie51

littledove44 wrote:

Despite this, my BG fit has my saddle set at 74, with a leg angle of 35 degrees.

The accepted range of knee angle in a bg fit is 35-25 degrees, with 30 degrees being the standard. Certain things will cause the fitter to deviate from 30 degrees, e.g. flexibility or reduction in core stability when saddle height is increased. It's is very unlikely that the 35 degree angle is mistake, more likely intentional and reasoned. You do get the off lazy BG Fitter, but they just tend to put everyone at 30 degrees. If a formula gets your saddle height correct that is through luck, and not by design. General rules are correlative, and, unsurprisingly generalised, inaccurate results are inevitable given the immense variance in human physiology between individuals. Bike fits are personalised, looking at direct cause and effect. They also account for variability in human physiology.

Trust the BG fit.