...done a couple of years ago down in Florida. I was getting ready to order a new bike and just wanted to check to see if I was doing anything I should be doing. Keep in mind that I have been riding a roadbike for 17 years now. The results of the fitting were good as the spec's showed that my position was similar to what the fitting suggested. One thing to keep in mind is that every fitter has their own ideas about bike fit. For example, the guy who fit me told me he always puts everyone's knee 1.5cm behind the pedal spindle (i.e., K.O.P.S) and the seat at the upper-limit. While you are getting fitted, I would suggest being an active participant in order to get a good fit; you are paying for it after all. If the fitter has the seat set at a certain position and it does not feel "right," then tell him or her. Also, I like to challenge some of the decisions. For example, if the fitter has a pretty good seat to handle bar drop, then ask why such a drop is necessary when you will not be racing.
I was fitted using the Serotta fitting system about a year ago when I bought my first road bike, and then had it done again resently as I have become more flexible and comfortable on a road bike since then.
I thought that it was great for me, because the first time I was buying a road bike, I did not know if certain discomfort that I was feeling while testing bikes was because they were the wrong size, or just because I was not used to the new position.
I liked the Serotta fit bike, because the fitter was able to get me into a position that utilized my leg power and pedeling in the most efficient way. It also helped greatly in fitting the correct stem length, handlebar height, handlebar width, seat height angle, how far forward or backward the seat is. I was alos unsure of the size bike that I should get or if it would be better to go with a custom frame and the fit helped this as well. I turned out that I fit well on a stock frame size. The fitter should also measure your flexability, ask questions about what kind of ridding you want to do, distances, frequency, etc, to help come to a conclusion on the best geometry for you.
In all, the bike that I ended up getting has been very confortable and it is nice now to have a relationship with the bike fitter who can better help me in the future when I buy new equipment or a new bike.
I had one done three years ago when I got back into cycling after many years away. In that situation, where you essentially have no current setup as a reference, it's useful. But it all basically comes down to putting you in a particular setup and asking 'how does this feel'. This is fine except that how it feels on a stationary bike for 10-15 minutes doesn't tell you all that much about how that fit will feel on the road over varied terrain for several hours. It might be more expensive, but I would suggest that if your current bike isn't too far off fit-wise, you invest in a stem or two, and play with your fit on your current bike until you find something that fits under real world conditions. Then you can use these measurements and a bit of trigonometry to evaluate new frames for fit, or to order custom.
I had one done & bought a Legend Ti. It fits great.
In researching this, I found that the process is great but can be individual fitter dependant (i.e. it is dependant on how experienced and qualified the individual fitter is). Because of this (& because of how much money I palnned to spend), I had two different Serotta fittings done by two different fitters. I paid for the one done by the fitter I didn't buy the bike from. I then identified differences between the two fittings in order to understand and decide on what I wanted my bike to be.
It's better if you have a particular frame in mind.
The fitter will set up the rig with frame angles of the particular bike you're interested in. If not, he/she will use a "generic" set up. When I had mine done it was with LS geometry in mind (odd sizes c-t). When I bought my first Merckx (even sizes c-c), I had to reconfigure the fit because the sizing sytems and frame angles were different.
My advice is to make sure that you are absolutely comfortable after about an hour on the rig and keeping in mind the type of riding you will be doing, i.e., don't set up reach with your hands in the drops if you do not intend to race often. Also, you really can't tell much from 5 minutes of spinning afer each adjustment is made. Don't get off the rig until you are comfortable for an extended period of time. Even then, I found that my initial fit was just that, initial. I've moved off that starting point as I've gotten older, less flexible and slower.
Make sure the LBS gives you a discount on any bike you buy after paying for the fit session.
I have to admit that I’m not familiar with the priorities used for a Serotta Fit or even if the fitter is given carte blanche in determining all aspects of the geometry, but I have a friend who recently did the Serotta Fit and the recommendations seemed a little odd to me. He is 6’-3” with a cycling inseam of 90.17cm. Here’s the fit info:
Recommended Fit (measurements center to center)
Seat Tube Length: 62cm
Seat Tube Angle: 73.5 degrees
Crank Length: 175mm
Saddle - Pedal Start: 100.8-101.2cm
Handlebar Width: 44
Handlebar Drop: 145-155mm
Top Tube/Stem Combinations:
59.5cm top tube
120-125mm stem with 96-100 degrees rise
1cm head tube extension
The first thing that seemed odd was the 73.5 degree STA. My friend emphasized a desire for comfort more than agility or responsiveness in a frame. Now when I look around at frames in that size range, it’s a very rare occasion that you see one with this steep of a STA. Is it possible that the fitter chose this STA to achieve KOPS with the saddle center fixed over the ST center line?
The other thing that seemed a bit “off” was the Saddle to pedal dimension. If I’m interpreting this correctly, you need to subtract the crank length to get the conventional Saddle Height measurement (ctr BB). This would get you a saddle height of 83.5cm. Now I know Lemond is not the Bible, but I wouldn’t think his Inseam x .883 would be off by as much as 5cm. If you take the inseam x .883 you get 79.6cm. Personally for me, Lemond’s formula for saddle height is only off about 0.5 cm, not 5.0 cm. I must be misinterpreting something here?
From what I’m hearing in the previous posts, the fitter has more influence than I had assumed. Does this seem like a reasonable fit?
I have never seen your friend or anything but it seems fairly normal. Do you know if these are the dimensions of the size cycle or (if you friend is ordering a custom bike) are these the dimensions from Serotta? the size cycle numbers are not what you look at when you use it. They simply show the relationship of the position. For example, if the stangle is 73.5 and the saddle is all the way forward on the rails, then you can slacken the ST to 73, leaving the saddle in the same position (retaining the same KOP) and have the saddle in the middle of the rails.
There is nothing that jumps out there as odd. The ST angle is more for the KOPS than anything, you make a frame more stable/relaxed/twitchy other ways (CS length, fork trail etc.)
As far as the Saddle height to pedal measurement, i am not that familiar with it, but unless you were at the fit, its really hard to determine why the fitter/rider ended up with the numbers they did. It could be that thats where the rider was most comfortable, maybe if it was any higher his hips would be rocking side to side and fitter decided to lower it.
If this is for a custom frame, when you fit someone, you design the frame so it is neutral (saddle rails in middle, stem length not too long or too short, 2 cm spacers, etc) so that as the rider's body changes, the bike can change with it. I knew a guy who stupidly got a custom bike with no spacers, sure enough when to change position he couldn't because there was not enough lee way in the front end.
The fitter does have a lot of influence, it is a science up to a point, than experience comes in, the ability to "read" the body as it rides a bike etc.
I see my assumption was correct regarding the STA - this makes sense.
The frame builder reviewed the Serotta Fit info, but actually did his own measuring as well and designed the frame based on both sets of info. He will pick up the bike on Sunday!
Still a bit confused on the saddle height though. The builder came up with something more along the lines of what I was thinking. The Serotta fit guy must have been using different reference points or something?
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