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View Full Version : Bike Fitting, help please...



Miranda
02-12-2009, 02:43 PM
I had my official bike fitting. There are a couple of things that are making my brain hurt:confused:...

Stand over: In doing my own reading in the traditional Lemond method of measuring, I thought you should have about an inch between your crotch and top tube when stradling the bike?:confused:

One of the bikes the shop suggested for me seems to fit my measurements, but the top tube I'm just above it with shoes, and on it barefoot (in geo theory, not that size in stock to see).

It (and some other small frames with that type of geometry--slightly relaxed--Cervelo RS 48cm, btw) would take a 650c wheel/tire. If you have a smaller wheel base, don't you have to work harder to cover the same distance?:confused: I know the 650c helps to avoid the "toe overlap" issue of getting a foot in the spokes with small frames. Which, I would not want that either.

The fitting measurements were very thorough of all parts of the body...

One thing I didn't expect was the inseam measurement. I had the tape measure on the stick tool thingy. The fitter told me to apply *firm pressure* as if sitting on a bike seat. Then, took the measurement. That made my 29" inseam become about a 30". Hmmm. I just don't know if I did it right (amount of pressure:confused:)??? They take a few measurements, then average for consistency there.

The end verdict was that I measure for: 49-50cm frame, 51.5-52cm TT, 60-70mm stem, 74 degree seat angle, 170mm cranks.

We did discuss a custom steele frame before measuring-- if I could not fit a standard geometry. Which, he had one of his customer's bikes there to show me. They do their custom steeles through Waterford.

He said with my measurements, he did not see a problem fitting me to a standard frame, and that I didn't need a custom build. Since they do handle them at the shop, I would think if I was indeed too much of a freak of nature to fit... he would have said "go custom". But, he did not.

We also talked about me finding a brand of bike frame they don't stock to supply and him doing the build of components. So, the options are open.

I'm just a little freaked about feeling like I should have more stand over???:confused: And I don't know about 650c tires??? :confused:

Hold my hand, Auntie Em... I'm frightened!:o (from Wizard of Oz if ya don't know it;)).

What are the thoughts of the wise TE?
(btw... have I told you lately I love you?:cool:)

Wahine
02-12-2009, 03:23 PM
The first thing is that touching the top tube is not a terrible thing. It's not ideal but it's likely one of the aspects of fit that can more easily be set aside and still have a very good fitting bike. Also, if you went with 650s your standover clearance would improve. The other way you could get more standover would be to look at bikes with a sloping top tube.

I would agree that your measurements don't seem to warrant a custom frame. You should be able to achieve a good fit with a standard frame.

A smaller wheel means a faster rotation at the same speed. So, with the same gearing you would have to spin at a higher cadence to go just as fast with a smaller wheel. That's not usually a bad thing for most of us. So 650s are not really a disadvantage mechanically, you either spin faster or just change your gearing to compensate.

melissam
02-12-2009, 03:49 PM
What Wahine said! :)

I have 650 wheels on two of my road bikes, and any slowness I experience is due to my bike's motor rather than its wheels. Besides, 650 wheels are generally lighter than 700 wheels, and as you know, rotational weight is exactly where you want to lighten up!

What are the disadvantages of 650's? Well, you probably won't be able to swap tubes/tires with someone in your group if you have a problem out on the road. Also, there's less 650 tires to select from. To add insult to injury, Continental doesn't allow you to choose different colors for your GP 4000's in the 650 size. What a travesty!! ;)

- Auntie Em (according to my nephew)

michelem
02-12-2009, 06:01 PM
Here are some threads you may find helpful:

http://forums.teamestrogen.com/showthread.php?t=8367

http://forums.teamestrogen.com/showthread.php?t=9302

http://forums.teamestrogen.com/showthread.php?t=11761

http://forums.teamestrogen.com/showthread.php?t=12285

http://forums.teamestrogen.com/showthread.php?t=17689

http://forums.teamestrogen.com/showthread.php?t=20126

fidlfreek
02-12-2009, 09:47 PM
Hey thats great news! Sounds like you finally found someone who is
1) knowledgeable
2) helpful

:) What a stunning combination!!

With a 49-50cm frame and a 51.5+ inch top tube (aka my bike!) you totally should be able to get 700cc wheels. If you're interested in bargain shopping there are many more options of wheelsets to choose from.

BTW, is a 60-70mm stem short enough to give you handling issues? Just wondering...someone more knowledgeable might be able to address that...

indysteel
02-13-2009, 05:42 AM
Just a few comments: As long as you can stradle the bike with your cycling shoes on, I wouldn't worry about the standover height. Ideally, you want a couple of centimeters, but I don't currently have that kind of clearance on my Bianchi, and it's never been an issue.

I won't comment on the pros and cons of 650c wheels, but I would agree with the others that, with your measurements, you should be able to find a standard geometry bike with 700c wheels. Also, toe overlap is a somewhat inflated issue. A minor amount of overlap isn't going to cause any problems. I have a bit right now on my Bianchi and I only notice it when I'm making a turn from a stopped position and that's easily fixed by making sure that my pedals are in the right position based on the direction of my turn. I'm currently working on designing a custom bike and have talked extensively to the builder and my fitter about the issue.

Based on your measurements, you might take a look at Bianchi by the way. I went through what you're going through a few years ago and have somewhat similar measurements as you. The 50cm Bianchi I ended up going with had the longest top tube/shortest standover (in a compact frame) that I could find. I have a longer torso relative to my short legs and Bianchi's geometry on their women-specific bikes is the only one that worked for me.

Jo-n-NY
02-13-2009, 06:52 AM
I had to do the samething to measure my inseam. I also measured 30". I ride a 51 Specialized Ruby Pro. I do not consider myself to have an extra long torso but I felt more comfortable on the 51 than the 48 cm. I forgot what the TT measures on this bike but will check when I get home. I do not have much clearence from the TT either when I have my cycling shorts on along with the cycling shoes.

My seat is in line or maybe just a bit higher than my head set. I could have fit a 48 then the seat would have been higher and making me bend lower to the handlebars to be more aero dynamic as opposed to me riding the 51 cm and my torso is more upright which I am more comfortable being. You should be able to reach the hoods with a slight bend in your elbow like you are shaking hands with someone.

According to my LBS, most people will fit two frame sizes. It all depends on the way you want to ride. Although I did not change anything, it is not out of the ordinary to change over a stem or anything else to perfect the size that you choose.

I hope this did not confuse you more.

~ JoAnn

Aggie_Ama
02-13-2009, 06:55 AM
I won't argue 650 vs 700 but will say I am so damn slow I can't tell the difference.

You will have trouble finding someone with a 650 tube on a ride but in a bind you can limp along by stuffing a 700 tube in a 650 wheel. Trust me, I did it when I rode 650s.

650s will limit you on rim replacements or upgrades, they just don't make that many. But they do look more proportional which I find pleasing to the eye and I know I shouldn't care but I am about the looks on the bike.

My 47cm Cannondale Synapse has 700cc wheels and I have not been able to do the toe overlap. If you are going to start cornering mad crazy or riding crits you might be able to but otherwise I agree the issue is overblown. Cannondale and Specialized (I am sure Cervelo with their excellence in engineering) have worked very hard to reduce toe overlap in their smaller frames, I think it is a lot less of a problem than people realize.

ilima
02-13-2009, 02:07 PM
I only have time for a quick comment, but the 60-70mm stem does sound a bike short. Steering could be a bit twitchy. I have an 80cm stem on a 49cm bike and I like the responsive steering, but I think I'm near or at the lower limit for stem length and decent handling. I also use short reach bars.

You are probably like me that you're just tall enough (I'm 5'4.5") to ride the smallest unisex sizes with 700c wheels, although 650c wheels may *technically* give you better geometry.

I have toe overlap and it's not something I worry about. It only matters when turning very sharply, which you can only do at very slow speeds. I wouldn't want my bike's geometry designed around toe overlap. I far prefer its geometry be based on performance and handling at speeds I actually ride.

Miranda
02-14-2009, 08:26 AM
Thank you ladies for those of you that have chimed in thus far. Been reading my thread on and off, just didn't have the time to type at the pc.

I read the old threads posted about the 650c wheels. That gives me some more to think about. Actually, it makes me feel better about it if I do get them. My initial reaction was that I felt dead set against it. But, after reading some of the old threads, I could discover a love for them. My mind's open now either way.

Also, that's good feedback about the standover. I would not have thought about the change in SO if you need to dismount on a hill. That could be not happy. But, not so common. However, I won't weight the standover so much in the overall fit and back-pedal my freak out a bit.

Still mulling it all over...

tulip
02-15-2009, 12:43 PM
I don't know much about 650c wheels, but presumably, the gearing on the 650c-wheeled bike will compensate for the difference in tire size. I ride a Bike Friday in addition to my Luna (700c wheels). The Bike Friday has 20" wheels. It goes everywhere and as fast as my Luna (but it also goes in a suitcase, which is nice). So wheel size is not a factor in speed--the rider is.

While your measurements may not require a custom frame, you may still want to look into one given your budget. Nothing is quite like having a bike that fits you.

ilima
02-15-2009, 01:42 PM
Definitely consider the 650c wheels. I've been coveting the Cervelo RS and one of the reasons is precisely because it has 650c wheels-and great geometry as a result-in my size (XS). If I bought a tri bike I would definitely get one with 650c wheels given my height.

That being said, my main ride is a 49cm unisex Merlin with 700c wheels and man oh man do I love my that bike!

Miranda
02-15-2009, 06:36 PM
I don't know much about 650c wheels, but presumably, the gearing on the 650c-wheeled bike will compensate for the difference in tire size... So wheel size is not a factor in speed--the rider is.

While your measurements may not require a custom frame, you may still want to look into one given your budget. Nothing is quite like having a bike that fits you.

That is a good point, Tulip. As always;):). The aquiant gym GF that has the custom steele I am going to see next week. I can't wait to see what's in their stable!


Definitely consider the 650c wheels. I've been coveting the Cervelo RS and one of the reasons is precisely because it has 650c wheels-and great geometry as a result-in my size (XS). If I bought a tri bike I would definitely get one with 650c wheels given my height.

That being said, my main ride is a 49cm unisex Merlin with 700c wheels and man oh man do I love my that bike!

The lbs owner/fitter pulled out someone's Cervelo tri bike in for service with 650s to show me. Oh my, what a tiny lil bike with tiny lil wheels I thought. But, if it fits the bill, so be it.