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I just recently went through a Specialized BG Pro-Fit (was about $200), and have to say that I'm super happy with the results and experience. The fitter was telling me about some others out there that cost a lot more and take 4+ hours and are more technical, or use more hardware, ie: lasers, though, I could not find them online with some simple searches.

Does anyone have any good experiences with others, or know of any others, and If you've done the Specialized BG Fit, did you like your results?

Edit: The BG Fit site goes in more detail

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should this be community-wiki? – fady Apr 26 '11 at 18:43
not certain if this should be CW or not. A CW question of bike fitting systems, with one method or system per answer, would be nice, but wouldn't fit with the existing answers. What question do you want to ask, aside from "tell me about other bike-fit systems"? As it is now, it's a pretty chatty question, and polling the community, but you got a good summary of some of the fit systems from @zenbike. I'm not well versed in bike fit systems; are there enough of them that we need an open-ended CW for this? Or can someone write an answer that summarizes all of them? – Neil Fein May 6 '11 at 17:33
@neil: yeah, i think it should be, as Im looking for many answers/ opinions, but that is just my opinion. – fady May 10 '11 at 16:37
up vote 9 down vote accepted

There are several good systems. I'm a certified BG fitter, as well as certified with the retul system. You're familiar with the BG system, as you've already been through it.

Retul is a system which uses power measurement and body position sensors on a 3 dimensional wire frame (virtual) reproduction of your bike and body. It allows an experienced fit specialist to see the skeletal body position without the intervening tissue interfering with the process. The power measurement is individualized to each foot, which means that efficiency can be improved and equalized, and you can see in real time how a body position change affects your efficiency on the bike.

In my opinion, they are both good fits, performed by a skilled bike fitter. A skilled fitter can be defined 3 ways:

  1. First, your fitter should ride a bike. Now, experienced fitters are often the older guys in a shop, so they may not be fast or aggressive riders. They may even be fat. But they still need to ride, to be able to feel the way new bike styles and fit ideas affect the way a fit should be done.

  2. The fitter needs to be experienced at bike fit. Preferably, years of experience. Learning to properly fit a bike is a time intensive process. It is best accomplished by an apprenticeship with an older, experienced fitter, in combination with classroom education on new tools and techniques. It is ok to be fit by someone who is learning, but it will take more time and you should expect more trial and error in the process.

  3. The fitter needs to be willing and able to examine the method of fit he is using and modify it to fit the needs of the rider. Meaning, a skilled and experienced time trialist needs a very different body position than a first time roadie looking to do a century in 6 months. A fit must take into account the fitness, experience, and intent of the rider. A fitter who fits everyone the same way is unlikely to do well for all of his or her clients.

So, to get back to the original question, there are many good fit systems, but what works best for you will depend on your intent, experience riding, and your fitness.

The BG fit is a great option for riders who are more interested in comfort than in efficiency. There is a balance point where comfort and efficiency meet up. That is what a well performed BG fit will find. But, there is a point where a racer, who is generally more interested in efficiency and power than in comfort.

There is a certain amount of pain and suffering that is expected of a rider who is looking to maximize performance, which will come at the price of a loss of comfort. The Retul fit does a great job of maximizing performance, bu the "comfort" zone it looks for is peak performance without actual damage to the body.

Both fit styles in the hands of an experienced fitter can be tuned to the rider. I find that quite often, though, there is bit of "I drank the Kool-Aid" mentality with fitters who have the classroom training, but not the flexibility or possibly the experience to recognize that every fit must be individualized to the rider.

So, I guess, what I'm saying is it is worth checking out other styles of fit, but it should be a style and a fitter which fit with your intent on the bike.

Make sense?

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how many fit systems exist? I really have no idea if there are, say, two or two hundred. – Neil Fein May 6 '11 at 17:46
@neil: i think they're only a few from what i've heard. – fady May 10 '11 at 16:35
thanks for the detailed answer – fady May 10 '11 at 16:37
As far as "systems", there are probably 30 organized systems. The FitKit was the first I became aware of in the late 80's. Serotta had an organized fit school combined with an adjustable stationary bicycle which allowed you to match the size and geometry of any bicycle to try it out. It is really the fitter, more than the system, which matters. – zenbike Jun 16 '11 at 13:49
The BG system link is now broken. – andy256 Jun 8 '15 at 10:49

If there's one thing I've learned about bike fit over the years, it's that it's rather controversial. I was strictly "old school" since I started cycling seriously in the mid 70s. Standard measurements for seat height, saddle fore-and-aft adjustment, knee-over-pedal adjustment, reach, etc. No high-tech goodies.
You used these "ball-park" measurements to get close and then let your body do the talking....

Much more sophisticated now, of course, but one has to wonder about the degree to which all the techie bells-and-whistles are just to justify the price.
Bottom line is simple.... If you're happy with the results, and you can ride efficiently without pain... You're golden. Every day I see cyclists who appear massively uncomfortable on their rides.

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thanks m. werner. also, the specialized bg fit is more medical than technical, but when the fitter told me about some high-tech ones that cost more, or are more in depth, i was curious if anyone else has done any of them. again, thanks for your answer. – fady Apr 26 '11 at 18:42

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