What exactly is a "good" fit?

Simple enough question, I hope... What exactly is a good fit? I'm assuming that comfort isn't the only thing: there's leg extension while pedalling (I've read that your leg should be just barely bent when the pedal is at its lowest), lean, etc... About to head down to the LBS, and I just need to be sure that what I THINK is right really is, given y'alls experience...

Thanks!

 

impossible to answer really. i slightly undersize my frames and shove a longer stem on. this gives extra stiffnes and responsiveness. i'm 6'5 17 stone and ride a 21" mtb. 23" flexes too much, bad news for ali frames. everyone has their own ideas about correct frame size. from looking around, i would say that the most common mistake people make is to buy frames that are too big.

another thing to consider is that frames are usually desined for people that have average proportions. there are ratios. i.e thigh length to lower leg length, fore arm to upper arm length, length of body to legs. can't remember what they are. most frames are ok for most people most of the time. you may develop slightly different preferences as time goes on............and then revert back to a stock length stem !!

for frame size a good starting point is if you can put you heel on the pedal with a straight leg when the crank is in line with the seat tube and at that point most people have 2-4" of post sticking out of a conventional road frame, although i like between 5-6" i ride about an inch higher than the above guideline. my mtb has about 8" of seat post sticking out.

there's obviously more to it than that. a lot is down to trial and error. it's quite a complex thing. i knew a guy who sold a colnago frame for next to nothing cos it gave him back ache, he thought the t/tube was too long. i think it was a combination of bad pedalling technique and crap posture. didn't tell him, though !!

you position will evolve too and it will depend on the type of riding you do and the type of rider you are.

oh well............

hope this helps, i can imagine that there will plenty who'll disagree with what i've said difficult subject !

p.s be careful some shops try and sell you a frame that is the wrong size cos that's the only size in stock, be careful.

 

Thanks for responding! I'm really starting out fresh, since my last bike was a 10-speed during high school (easily 20 years ago)... I guess I'm really looking for tips & tricks on what to watch out for to avoid a) getting sized incorrectly at the LBS, and b) what to watch out for as I ride/break-in to make sure I'm not doing something dumb or wrong that'll cause aches or injuries. I'll be getting an MTB very shortly (driving to Santa Barbara tomorrow for a fitting) and the more educated on how sizing works will be good...

Thanks for the responses!

 

You really need to watch out for those LBS's and go with the shop that will let you put on the most time on a frame before you buy. The LBS where I just bought my dale R600 give 30 day test rides if you buy a bike, that way I can exchange it for a different size or model within 30 days.

Here's what happened to me when I bought my first road bike a couple weeks ago and I was dealing with what size to buy:

1) Shop A recommended a 60cm, a week later, a different guy at Shop A recommends a 58cm

2) Shop B recommends a 58cm by having me test a 56cm and deciding I needed a size bigger (I'm 6' 1" with a 35" inseam btw)

3) Shop C recommends a 60cm

Now none of these shops had the model I wanted in stock, they were going to have to order it so they weren't trying to push something they had in stock off on me.

In my experience I did about a month worth of research before buying and got more confused the more I talked to my LBS's 'cause of all the conflicting size recommendations. I finally decided to trust the decision of the shop that had the best service and the 30 day test ride.

So now I have a 58cm bike that is too small but luckily I can exchange it for a 60cm. If you have a LBS that will do that for you, buy there because only your body can tell you if you have the right size and you can't tell by only a test around the parking lot. For me after a few rides on the 58 something just didn't feel right. If found a shop that had a 60 that let me go on a several mile test ride and noticed an immediate improvement.

I hope this helps, you just have to test ride as much a possible.

 

Read the information on the "Fit Links" at the fitStik site URL:
http://www.cyclemetrics.com/
and
http://www.peterwhitecycles.com/fitting.htm
and Biodynamic Fittings at URL:
http://www.cronometro.com/
This should give you some information that will allow you to understand many of the basic approaches to a fit.

 

The article at www.peterwhitecycles.com was very helpful as I have been contemplating changes myself.

Thanks daveornee.

 

Hi SoloHiker. The good news is, getting the "right fit" is not directly related to "buying the right size". In buying the right bike, there are many more things to consider then "if it fits right". Most bikes can be adjusted/changed so that it will give you a good fit. Most LBS's will be able to tell you if a frame size works for you. After you establish that, they should be able to give you the option of the length of stem that should be put on, etc. However, when it comes to fine-tuning the fit, much of that is up to you. The REALLY big ones to ensure you adjust well are:

1) Seat height
2) Seat fore/aft position
3) Cleat position
4) Handlebar height
5) Stem length

The difference of having these adjusted right is the difference between "comfortable vs uncomfortable", "Injury vs Health", and "Power/Speed vs Inefficiency". Fit is a critical part of cycling. However that doesn't mean that you should completely stress over which bike to buy.

If you're a beginner, I would advise that you buy a bike that will meet what you are planning on doing. If you have any ambitions to race or even have any desire to play with the idea of racing; Buy a slightly more aggressive frame (ie, not completely upright like a touring bike or completely intro mountain bike). At minimum, you'll have fun knowing that you're riding something a little sporty.

If cycling ends up being for you and you know that you want to bring it up a couple levels. Then realize that no matter how much thought you put into your first bike, you'll want something different in a couple years. By looking at the forums and reading various books/magazines, etc, you'll come to realize what terms like "upright", "twitchy", "road feel", etc all mean. And you'll also know what characteristics best suite you. There's no science, advice, or website that will actually be able to answer that one for you.

If you're really nervous about what kind of fit the bike shop will give you, give this site a try. It's kind of a sizing calculator: http://www.zinncycles.com/fitform.aspx

For bike fit, I have found this site to be very good as well: http://www.slowtwitch.com/mainheadings/techctr/bikefit.html

Hope that helps.