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Gtane

I'm interested to know how we all get the right fit for our bikes as there are many ideas and theories in the world from the manual to the computer and I thought I'd cast the question to see what we all do.

Is there a perfect or ideal solution?

Are there many solutions?

Do we adjust for comfort or do we go all out for efficiency?

I use a manual method based on my inside leg plus about 9 to 10% (when the crank is lined up with the seat tube in its bottom position) for saddle height while ensuring that the hips don't rock. This are the Guimard or Loughborough University methods (slight difference in the outcome but very close) and either calculation works for me. In my earlier days I would simply study the pros and other riders, from photos, to try to achieve a position that felt comfortable while remaining efficient. While time consuming, I was interested to find that I wasn't that far from the above two methods that I now use.

I base my handlebar distance and height on elbow position with the knee, when on the tops of the drops (between the outside back corners of the bars and the brake hoods). I then adjust bar height when holding the drops so the saddle allows for normal blood flow!

For saddle position, I tend to find that I move about quite a bit depending upon the terrain and so usually set it up in a neutral position so allowing for forward and aft positioning. My neutral position roughly gives a perpendicular line from just behind the knee cap to the centre of the pedal spindle (leading knee) when the cranks are horizontal.

I realise that bike fit ties in with frame geometry, tube length, etc. and it's not always possible to have the very same position on each bike, particularly where bike collections are concerned, but wondered if we have common ground on theory and practice, or is there a wide variance?

For the sake of clarification, I'm referring to the set-up for sports and race machines.

Thanks

Tim

scozim

I don't think I'm even as technical as you are, Tim. I spent a lot of time this year trying to get my fit on the Bianchi right because I changed saddles (which changed my saddle height - thinner vs. thicker). I ended up going back but then was messing with the fore and aft on my old saddle to get it right. I usually set the fore/aft position so my knee, in the horizontal position, is slightly behind the pedal spindle. I have found this gives me better leverage when fighting the wind (we have a lot), going up hills and also riding home from town because it's a gradual climb for 9 miles. I finally had to raise the stem a little to get a little more comfort.

On the Gitane Sprint, the handlebar stem is shorter - around 90 mm - so, while the frame geometry is the same on both I feel more compact. My saddle is back but the handlebars are closer. I actually am pretty comfortable with this set up even though a little more quadricep involvement than I'm used.

The TdF is really comfortable right now. In fact, on my ride yesterday (before the rear wheel problem) I was in awe how it was the most comfortable of all my bikes. I haven't adjusted it much, other than saddle height, since I got it. The prior owner was a professional bike mechanic and seemed to have it set up pretty well.

A friend of mine sent me an interesting article on bike fit which has some good information on handlebar set up:
http://www2.bsn.de/Cycling/articles/uscf-bikefit.txt

Gtane · Last edited by Gtane on Thu Nov 27, 2008 1:02 pm; edited 1 time in total

Scozim,

Thanks for your thoughts. I'd say that I am more trial and error rather than technical. I really used to try hard to get the right fit in the early days and I made many errors, I still do, but I try to tweak and adjust. I'm also finding that as I get older I need a more flexible position rather than a position which is too severe - back to the blood flow thing again (although all's fine in that department!).

It sounds like you have a similar approach to saddle position as me. I too slide back when going up hill and even on the flat and probably ride a little further back than the theory applies. This is probably quite common, in fact logical, but does show that saddle position (aft and fore) allows for some movement. It seems that it's not so set in stone.

Thanks for the article, I'll take a look.

My stem length (top tube length depending) usually goes from 90mm to 120mm but I try to keep my position on the bike the same. It's not always easy when you have different machines. For some bikes I say, ahh, just enjoy the ride...

There just seem to be so many theories and practices regards bike fit, perhaps because we're all different. Can a single formula fit all?

Here are many links to bike fits, including the Guimard method (top one within the links);

http://www.cyclemetrics.com/Pages/FitLinks/bike_fit_links.htm

Tim

verktyg

The best fit is the one that is most comfortable for you on a long ride. Cool

This is my pet peeve in cycling! I've heard many bicycle fitting experts over the years and it infuriates me when I hear the recommendations from most of them! Evil or Very Mad

When I first started serious cycling in the early 70s I read the competitive cyclist's bible, the Italian C.O.N.I. book cover to cover a number of times.

I was 30 years old and after trying all of the recommendations in the book I realized that this applied more to younger competitive cyclist's than to someone like me who had been riding casually for many years.

Many fit experts are like the ballet choreographer George Balanchine. He forced his young ballerinas into uncomfortable, unnatural positions for the sake of performance (artistic style).

The goal in developing competitive cyclists is to enable them to ride in a position that is both most aerodynamic and provides the most efficient use of their individual physique. It's easier for a younger person with a more flexible body to adapt to these riding positions.

After a certain age not many people's backs and necks are that flexible, especially after their abdomens start to develop! Laughing

I have large feet, short legs, a very long torso (with a well developed abdomen), a short neck plus I wear glasses so I don't like to have to look over the top of them. NONE of the C.O.N.I. recommendations worked for me. I ride with my seat all the way forward, I use short stems and short reach bars plus I prefer frames with a short top tube and a steep seat tube angle which pushes me forward over the cranks.

My riding partner just turned 46 and has been going through a mid life crisis. He's been doing some hard core riding lately. During the past year he fine tuned his seat, seat position, stem length and bar height. Recently he consulted a fit Nazi who had him change everything. After several hard rides he started developing serious back pain that has caused him to reduce his amount of riding plus change his bike back to the way it was before.

Here's a link to an article by Ben Serotta that discusses a lot of fit issues. The big point that he makes is that most fit experts work off of measurements and data based on averages rather than personal requirements. They try to force fit you to the average, so beware of what these experts recommend.! Shocked

http://www.cobr.co.uk/e-cobr_information/t_and_r_section/sections/terminilogy_technique/advanced_bike_fit/introduction.shtml

P.S. A lot of cyclists are not aware of how to adjust their bike to fit them properly. They assume that they need to adjust their body to an uncomfortable fitting bike. After a short amount of time they give up and stop riding.

Chas. Twisted Evil

Gtane

Chas,

That's great information, thank you. I have long arms, longish legs and a medium torso with medium feet (as well as the abdomen thing going on!), and tend to have a reasonable reach but that presents problems with the back and head, as you say. I'm not comfortable with the new 'sportive' position at all (long head tube) and find comfort in a more traditional position, and can ride miles quite happily that way. I find the higher sportive position, for me, less stable on descents.

I'm interested too regards the experts and their thoughts because they are all so different. It really can be quite confusing. I had a quick search on You Tube recently and there are so many differing views, some great some not so great but as a beginner this must be confusing. Not to mention the further information, in word form, on the net.

You make a good point regards your riding partner and a new position. It's easy to charge a customer to refit them but is it really necessary - only an real expert will know.

Thanks for the article. I'll take a look.

Tim

vanhelmont

Many years ago I used something from Sloane, that suggested the saddle top to the pedal was 107% of your inseam, if I remember rightly (or was it 107.5%). I think it was based on Loughborough U. My frame was just a little small for me, so I ended up with the bars relatively low, throwing a lot of weight on the handlebars. That didn't bother my neck or back, but on long rides on rough roads I'd get sore hands and wrists. I found that saddle to pedal length worked really well for me.

Recently (when I got a decent bike again) I got a book written by Lemond in the 70's, using the fit Guimard worked out. The saddle height ends up about the same as I had before, and I push the saddle back so my knee is over the pedal. I have a 100 mm stem, and sometimes I think it might be a little more comfortable if it was a little shorter, but mostly it seems good. I have the bars as high as the stem will allow, a few cm higher than Greg did, but then he said bar height was optional.

Gtane

Vanhelmont,

Thank you for your comment too and like you, I found success in the same fitting models.

Chas and Scozim,

Thank you both. I've read your recommended articles and they have some very useful information. Much appreciated.

Tim

cooltech

I find that my leg to peddle distance to be most important. I don't want the legs to get weary as they are taking me the distance when other conditioning factors are right. Upper body adjustments can be made as needed that the other suggestions show. Great thread!
cooltech Cool

Vince