Bike fit : not exact science

[weisan]

Bike fit numbers Mar. 21, 2018

Cyfac
Saddle Height: 74
Setback: 5.2 (74-68.8)
Cockpit: 52.5 (to stem), 65 (to hood)
Bar drop: 4 (98.5-94.5)

Cervelo
Saddle Height: 74
Setback: 4.2 (73.5-69.3)
Cockpit: 51.3(to stem), 64 (to hood)
Bar drop: 3.0 (97.5-94.5)

Giant
Saddle Height: 74
Setback: 6.8 (79-72.2)
Cockpit: 52.5 (to stem), 65 (to hood)
Bar drop: 2 (97.5-95.5)

Richard Sachs
Saddle Height: 74
Setback: 5.7 (73.5-67.8)
Cockpit: 51.5 (to stem), 63.5(to hood)
Bar drop: 4.3 (96.8-92.5)

Merlin
Saddle Height: 74
Setback: 4.1 (73.8-69.7)
Cockpit: 51.3 (to stem), 64.2(to hood)
Bar drop:.0.3 (97.3-97)

Rivendell
Saddle Height: 74
Setback: 7.5 (75.5-68)
Cockpit: 52.5 (to stem), 65.5(to hood)
Bar drop:.0 (97-97)

Hampsten
Saddle Height: 74 cm
Setback: 7.3 (75.8-68.3)
Cockpit: 52 (to stem), 63(to hood)
Bar drop: 2.5 (98-95.5)

[Blown Reek]

Well, seeing how your saddle height is the same among all four bikes, I'd say that it's pretty exact.

However, if you have set it up to where you are "comfortable", you might not be in an ideal position (regarding saddle height and fore/aft). But since you're constant, that's what counts, because your saddle height and saddle fore/aft is the most important part of fitting. Everything else is personal preference.

Try adjusting your saddle height differently between each of your bikes. If you do that, your bioperformace will change, whereas reach and drop don't affect it (as much).

[Kontact]

Did you actually pay for 6 different fits?

[ultraman6970]

Don't know about him but some people does.

Did you actually pay for 6 different fits?

[David Tollefson]

Do you have the same saddle on each bike as well?

[ripvanrando]

Science?

[glepore]

Fit is like saddles, some people are sensitive to every mm, some folks adapt after a few minutes. I'm in the later group. I can tell the difference but unless I'm at an extreme it usually works after a bit.

Ask me after 70-80 miles, and I might feel differently, but I don't spend much of my riding time on rides of that distance.

[Kontact]

Don't know about him but some people does.

Yeah, I'm genuinely curious if all 6 are the result of professional fits, or if there wasn't even that much "science" involved.

But I don't understand why anyone would get a bunch of road bikes individually fit instead of transferring the position to all of them. (Which usually goes with some refinements due to different brake levers and that kind of thing, but not anything that would cause the same saddle to be positioned 3.5cm differently per bike.)

[Blown Reek]

...but not anything that would cause the same saddle to be positioned 3.5cm differently per bike.)

Do you have the same saddle on each bike as well?

Perhaps.

[Gummee]

Fit is like saddles, some people are sensitive to every mm, some folks adapt after a few minutes. I'm in the later group. I can tell the difference but unless I'm at an extreme it usually works after a bit.

Ask me after 70-80 miles, and I might feel differently, but I don't spend much of my riding time on rides of that distance.

I'm the former. I jokingly refer to saddle position as 'I have a princess and the pea' butt/legs.

M

[Pegoready]

You have several bikes that fit differently. And your point is?

[fiamme red]

http://cdn.velonews.com/wp-content/uploads/2014/04/19_20140406_%C2%A9BrakeThrough-Media_3S1A3396.jpg

http://www.ldillon.net/home/tall-bike/Tall_Bike_Billings_MT_.jpg?attredirects=0

[ripvanrando]

You have several bikes that fit differently. And your point is?

Maybe that there are large error bars around "fit"?? Lots of tolerance aside from saddle height??

3mm variance on saddle height is my limit

Reach is more related to balance and setback....an extra 10 mm won't kill me

I think this is what Weisan is saying.

[Mzilliox]

it doesnt bug you that one saddle is setback 3mm more than another? that kind of thing would drive my nuts nuts. reach all seems in order, i have a bit different reach and drop on different bikes, but saddle position relative to BB is not something my legs change lengths for.

to each their own i guess

[Kontact]

it doesnt bug you that one saddle is setback 3mm more than another? that kind of thing would drive my nuts nuts. reach all seems in order, i have a bit different reach and drop on different bikes, but saddle position relative to BB is not something my legs change lengths for.

to each their own i guess

Lot's of folks have their touring bikes set up with more set back than their racers. And I added set back to one casual racer I have to make up for a short stem I wanted to use - it just means my drop is going to be less.


But I wouldn't move the saddle forward of my race bike position - that changes things a lot more than moving it back.

[oldpotatoe]

So which one ‘fits’?

[David Tollefson]

Here's a data point for you: I'm running a Kinekt seatpost on my bike now. Completely un-preloaded, so it moves up and down (they recommend in their set-up procedures to dial in preload so that the saddle doesn't rise at all when you unweight it). But I was making as little as 2mm height adjustment to it yesterday to get it in the "right" position. Fore-aft is more tolerant, as there isn't exactly one position that you can occupy on the saddle. Likely there are differences in the saddles (how wide at certain points along its length) that make up at least part of the difference in the setback measurement.

[.RJ]

In chasing after some lower back (L5/S1) and hip flexibility issues for the past few years I'm turning my fit upside down. A lot of it is trial and error, at this point.

I'm planning on checking in with a local fitter who's also a PT, as well, but for now I'm hoping to establish some parameters to work against.

Right now, my saddle is down 20mm from where I've had it for years - no impact to power output that I can tell. Same with shorter and longer reach to the bars. We're a lot more adaptable than we think. If it feels weird, ride it for a few hours and then maybe becomes new normal.

[Fishbike]

There is a inverse relationship between bike fit precision and the number of bikes one has / wants.

[Cloozoe]

There is a inverse relationship between bike fit precision and the number of bikes one has / wants.

Makes perfect, epigrammatic sense. An aside: "bike fit precision" is about as oxymoronic a phrase as one could construct.

[simplemind]

OKAY weisan pal, see what you went and did!? :bike:

[Kontact]

Maybe Weisan likes to vary his weight distribution depending on where the frame is damaged.

[Kirk007]

my set back varies a little by saddle. When I had Tom K fit me for my Spectrum he had me do a bunch of up and down sprints in and out of saddle and watched where my ass wanted to settle in on the saddle. So, its a bit different on a Specialized toupe than a Fabric than a Brooks C17. I really should just figure out once and for all which saddle works best but that also depends on the bike to a degree. The bike with the C17 has a different purpose than the more traditional road bikes with other saddles so I get some variability in numbers. Saddle height can also vary by pedal type and crank length. Oh the hardships of multiple bike ownership.

[oldpotatoe]

Maybe Weisan likes to vary his weight distribution depending on where the frame is damaged.

POW...post of Wednesday :eek:

[hainy]

What are you trying to say?

You have no idea what is your best fitting position.

[wallymann]

There is a inverse relationship between bike fit precision and the number of bikes one has / wants.

not true. all my bikes have the exact same saddle height + setback + saddle-handlebar drop specs...and saddle-stem reach within a 5mm window. saddles and bars are all the same, too.

http://majortaylorcycling.org/bikes/walter

getting that level of consistency requires committment...to get there i've invested a small fortune in stems.

http://brown-snout.com/cycling/misc/stem-sanity.jpg

[mtechnica]

Bike fit numbers Mar. 21, 2018

Cyfac
Saddle Height: 74
Setback: 5.2 (74-68.8)
Cockpit: 52.5 (to stem), 65 (to hood)
Bar drop: 4 (98.5-94.5)

Cervelo
Saddle Height: 74
Setback: 4.2 (73.5-69.3)
Cockpit: 51.3(to stem), 64 (to hood)
Bar drop: 3.0 (97.5-94.5)

Giant
Saddle Height: 74
Setback: 6.8 (79-72.2)
Cockpit: 52.5 (to stem), 65 (to hood)
Bar drop: 2 (97.5-95.5)

Richard Sachs
Saddle Height: 74
Setback: 5.7 (73.5-67.8)
Cockpit: 51.5 (to stem), 63.5(to hood)
Bar drop: 4.3 (96.8-92.5)

Merlin
Saddle Height: 74
Setback: 4.1 (73.8-69.7)
Cockpit: 51.3 (to stem), 64.2(to hood)
Bar drop:.0.3 (97.3-97)

Rivendell
Saddle Height: 74
Setback: 7.5 (75.5-68)
Cockpit: 52.5 (to stem), 65.5(to hood)
Bar drop:.0 (97-97)

Hampsten
Saddle Height: 74 cm
Setback: 7.3 (75.8-68.3)
Cockpit: 52 (to stem), 63(to hood)
Bar drop: 2.5 (98-95.5)

This is awesome,, I have a notebook with the exact same numbers, as well as bike weights and descriptions, going back for years.

[weisan]

getting that level of consistency requires committment...to get there i've invested a small fortune in stems.

http://brown-snout.com/cycling/misc/stem-sanity.jpg

http://alicehui.com/bike/Stems/IMG_4414.JPG

[duff_duffy]

“There is inverse relationship between bike fit precision and the number of bikes one has / wants.”

This quote definitely explains my situation! I have everything from 20 inch bikes to road bikes from 52-59cm. I got fit professionally once and saw no noticeable difference in comfort or speed than any of my supposedly ill fitting bikes. Just find a saddle you like and make sure you can reach the pedals and brakes.

[Kontact]

“There is inverse relationship between bike fit precision and the number of bikes one has / wants.”

This quote definitely explains my situation! I have everything from 20 inch bikes to road bikes from 52-59cm. I got fit professionally once and saw no noticeable difference in comfort or speed than any of my supposedly ill fitting bikes. Just find a saddle you like and make sure you can reach the pedals and brakes.

Lot's of people don't require to be "fit". They can accept a range of positions and are able to use old fashioned techniques to find a decent position. Those people are usually less motivated to get a fit and benefit less from them.

But they still benefit.


my set back varies a little by saddle.
It should. Saddle makers don't all get together and decide that everyone's hip joint should be located 22.3cm behind the saddle nose. Saddle shape is pretty arbitrary.

[pasadena]

:eek:
Brailsford must be reaching for the jiffy bag! Put his marginal gains to shame!
http://alicehui.com/bike/Stems/IMG_4414.JPG

[wallymann]

WEISAN...my brother from another mother!

[weisan]

http://cdn.velonews.com/wp-content/uploads/2014/04/19_20140406_%C2%A9BrakeThrough-Media_3S1A3396.jpg

http://www.ldillon.net/home/tall-bike/Tall_Bike_Billings_MT_.jpg?attredirects=0

http://cdn.velonews.com/wp-content/uploads/2018/03/20186536-420913-800x531.jpg