General Cycling Discussion - Trouble with bike sizing (or, why do I have to be so short?!)

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I've been looking at various CX bikes, and most manufacturers only make maybe 49-50cm as their smallest size.
The standover height for most of these bikes are ~28" when my inseam is 26"... obviously this is a problem.
The only CX bikes I've encountered with smaller frame sizes are the Redline Conquest and Surly Cross-Check (they go down to 44cm I think) - the Conquest seems okay but most of the LBS around here only carry the Pro model, and both the Conquest Pro and Cross-Check are out of my price range.
What to do? Are there any sub-$1100 CX bikes that make frames under 50cm?
Strawbee
04-16-09, 06:16 PM
Umm, a woman's bike? ^_^ It bypasses the standover problem. I wouldn't be able to find a bike at all if I wanted to find a men's style one, because I'm really short too. I'm only 5'0".
I've never heard of women's specific CX bikes though... and I'm really set on buying a CX bike.
c_m_shooter
04-16-09, 07:38 PM
Smaller sizes create problems with frame geometry with 700c wheels. If I were you I would get an old rigid mountain bike and put some skinny tires and drop bars on it.
Okay I realized that maybe standover height isn't the best way to decide whether a bike fits me or not...
I ride a 16" mountain bike (with my seat pretty low)... and by using that weird calculation (multiply by 2.54 and subtract 1.3 or something) that gives me... less than 40cm?!
Do I have to look into kids' road/CX bikes?! This development is very depressing...
The standover height for most of these bikes are ~28" when my inseam is 26"... obviously this is a problem
1. Put shoes on.
2. Measure from the floor to your pubic bone/crotch, compressing any soft tissue and moving your man bits out of the way.
3. Report back.
I bet, if you "inseam" is really 26", then your can handle a 28" standover.
Sirrus Rider
04-16-09, 08:37 PM
I've been looking at various CX bikes, and most manufacturers only make maybe 49-50cm as their smallest size.
The standover height for most of these bikes are ~28" when my inseam is 26"... obviously this is a problem.
The only CX bikes I've encountered with smaller frame sizes are the Redline Conquest and Surly Cross-Check (they go down to 44cm I think) - the Conquest seems okay but most of the LBS around here only carry the Pro model, and both the Conquest Pro and Cross-Check are out of my price range.
What to do? Are there any sub-$1100 CX bikes that make frames under 50cm?
I feel your pain. I'm 5' 4" and I ride a 47cm road frame.
Sirrus Rider
04-16-09, 08:52 PM
Smaller sizes create problems with frame geometry with 700c wheels. If I were you I would get an old rigid mountain bike and put some skinny tires and drop bars on it.
The whole 700c on smaller frames is an overdone wives tale left over from the toeclips & straps days. I'll break it down so you tall folks will understand and cease repeating this apocryphal knowledge. The only time overlap is an issue is at VERY VERY SLOW SPEED. How slow? We are talking under 5 MPH where you might need big swings of the bars to keep your balance. Also this would be with toe clips if your running clipless your toes will be over the pedals and even with the big swings the wheel will miss your toes by Nths.
Thanks for your co-operation in putting this wives tale to bed.. :thumb::p
Thanks for your co-operation in putting this wives tale to bed.. :thumb::p
Actually it's not just toe strike. There gets to be a point where the 700c is into the seat post or they can't get the seatstay geometry correct for there to be a reasonable standover. It's an overall geometry issue given wheelbase and tire diameter getting the rest of the measurements to come into reasonable specs so that the rest of the bike fits. My wife is 4' 11" tall and rides a 47cm on 650's and even then the bike looks like a kids bike to me. No way 700's are going on it from a geometry standpoint.
Zephyr11
04-16-09, 10:20 PM
Independent Fabrications, Seven, and Serotta will all customize a cross bike for you. It'll be kind of pricey though...
Soma Fabrications Double Cross is a steel frame that comes in 42cm and 46cm, and is a lot cheaper.
You can put 700c's on a reasonably small bike. My roadie is a 48cm and has 700c's. It does depend on the geometry though...my tri bike is also a 48cm and has 650c's, and there's no way bigger wheels would ever fit on that bike.
deraltekluge
04-16-09, 10:44 PM
I ride a 16" mountain bike (with my seat pretty low)... and by using that weird calculation (multiply by 2.54 and subtract 1.3 or something) that gives me... less than 40cm?!Why would you do that? Multiplying by 2.54 converts from inches to centimeters, OK...but why SUBTRACT to get a size? If the other bike has a more nearly level top tube, you'd want to increase the number to get the new size.
c_m_shooter
04-16-09, 10:49 PM
The whole 700c on smaller frames is an overdone wives tale left over from the toeclips & straps days. I'll break it down so you tall folks will understand and cease repeating this apocryphal knowledge. The only time overlap is an issue is at VERY VERY SLOW SPEED. How slow? We are talking under 5 MPH where you might need big swings of the bars to keep your balance. Also this would be with toe clips if your running clipless your toes will be over the pedals and even with the big swings the wheel will miss your toes by Nths.
Thanks for your co-operation in putting this wives tale to bed.. :thumb::p
If this is true, then why do I get pitched off my Cross Check periodically when my toe slams into the front tire? I know to watch where my pedals are, but still strike the front wheel quite a bit on technical sections of trail. Not that toe overlap is the only issue as others have pointed out.
grimace308
04-16-09, 11:55 PM
Also this would be with toe clips if your running clipless your toes will be over the pedals and even with the big swings the wheel will miss your toes by Nths.
you lost me there boss. the ball of your foot is over the pedal spindle no matter if youre on clipless or using toeclips.
its not just overlap, but some there are some issues with geometry when youre running 700s on a really small frame. its late and i cant remember what was said, it was also 20 years ago, but it was valid then and still valid...whatever it was that they said.
Sirrus Rider
04-17-09, 12:01 AM
If this is true, then why do I get pitched off my Cross Check periodically when my toe slams into the front tire? I know to watch where my pedals are, but still strike the front wheel quite a bit on technical sections of trail. Not that toe overlap is the only issue as others have pointed out.
Maybe you are related to Big foot? :p:lol::D:innocent:
I know I could easily go to a LBS and get help for sizing, but the stores I've visited didn't have on-floor models that were under 52cm.
I'll go check out a few more road/cross-specific stores and see if I can get any help there... is it bad practice to go into a store and get them to help you find your proper bike size, and not buy a bike from them?
Are there any sub-$1100 CX bikes that make frames under 50cm?
Bianchi Volpe (http://www.bianchiusa.com/09-bicycles/09-d2-special/09-d2-volpe.html). Comes in a 44cm and a 49cm and is $1099.
A friend just bought a 44. Really nice bike.
garysol1
04-17-09, 06:08 AM
My wife is 4' 11" tall and rides a 47cm on 650's and even then the bike looks like a kids bike to me. No way 700's are going on it from a geometry standpoint.
Better not tell Specialized that. All of there road bikes are 700c including there 44cm size.
Longfemur
04-17-09, 10:30 AM
With an inside leg length of 26 inches (assuming you measured that correctly), you need to go to smaller wheels than 700c. A small woman's bike (WSD) may have a short seat tube with a sloping top tube, but all that means is that you get a 50-51 cm sized bike with a shortened seat tube. It's still too big for you length-wise. Bikes like that are fine for recreational bikepath riding and you can certaily hop over the top tube, but if you go beyond that as a cyclist, you can never really make such a bike fit you properly if it's any kind of road bike. To properly fit on the smallest practical size for a roadish-type bike with 700c wheels, you need an inside leg length of about 29 inches, maybe 28 at the very least.
MichaelW
04-17-09, 11:43 AM
Some useful advice here (http://cxmagazine.com/small-cyclocross-bikes-kids-juniors-short-search).
A few things to bear in mind with small bikes:
There are 2 components to standover height:
The length of the seat-tube from BB to TT
The height of the BB from the ground.
Most bikes use a constant BB height across the size range from xxs to xxl. Look at any geometry chart and see for yourself.
Small rider can use small cranks and can benefit from a lower BB height, you dont lose pedal clearance (compared to Med size) but you do get lower standover and it makes mounting and dismounting much easier.
I would strongly recomend a CX bike with 26" MTB wheels.
The Terry Valkryie (http://www.terrybicycles.com/cycling_savvy/valcross)isnt pink but more than your budget.
black_box
04-17-09, 11:57 AM
you might try a fuji cross bike in 49cm (cross comp should be in your budget), it seemed to have a lower standover height than other cross bikes. I sometimes get toe overlap at low speed, haven't fallen yet because of it though.
For the short riders, does anyone use a crank smaller than 170mm?
So I went to an LBS and today they had a 46cm Devinci Tosca there... it fit the same as some 50/51cm road bikes I've tried, but more upright and pretty comfortable.
So I guess I'm looking at ~46cm for a CX bike...
stapfam
04-18-09, 06:52 AM
No pics are posted of smaller bikes but I only have a 30" inseam. The bike size that fits me is a 51cm. Standover height is one measurement I do not use for a bike fitting.
With the saddle at the right height for pedalling- I cannot touch the ground, and in fact on some 51cm frames I can only touch the ground on tip-toes if I am sitting on the Crossbar. The measurement I go on is the one that matters- Does the bike fit when I am riding it.
I have got into Compact frames and by choice, and having a top rate LBS that sells them- Into Giant bikes.
Giant do a CX bike in the small size Link to their web site is
http://www.giant-bicycles.com/en-US/bikes/road/2299/32184/#
And attached is my S size frame set up for a 30" inseam And as you can see plenty of room for lowering the saddle and the bars. Whether the Top Tube is short enough -may be a different matter though.
But Compact frames are being made by most manufacturers so keep looking- Frames for us shorties do exist.
stapfam
04-18-09, 07:03 AM
And the annoying thing is- The UK Giant site does list an XS- the 46cm equivalent- in the TCX range- why it is not done in the US is for you to find out.
http://www.giant-bicycles.com/en-GB/bikes/road/2422/32352/
Any particular reason why it has to be a CX bike?
I have short legs/long torso, and I discounted CX bikes early on because they all seem to have a high bottom bracket, which inevitably leads to high standover height relative to the top tube length.
A couple of options spring to mind:
(a) A 650C bike. In Australia you can buy something like this:
http://www.apollobikes.com/bikes09/id/44/cid/42/parent/0/t/bikes09/title/Purzuit
Apollo is a Pacific Brands company. I would guess they would sell something similar under a different brand name in the US.
I was sure Felt made a similar bike, but I can't find it on their web site.
(b) A mountain bike frame, with rigid carbon forks, road gearing, road tyres, drops, etc. This could be expensive and time consuming, but it might be the best way to dial in exactly what you want.
The issue was also discussed in this CX article:
http://cxmagazine.com/small-cyclocross-bikes-kids-juniors-short-search
Any particular reason why it has to be a CX bike?
I have short legs/long torso, and I discounted CX bikes early on because they all seem to have a high bottom bracket, which inevitably leads to high standover height relative to the top tube length.
[...]
(b) A mountain bike frame, with rigid carbon forks, road gearing, road tyres, drops, etc. This could be expensive and time consuming, but it might be the best way to dial in exactly what you want.
I just really like the whole concept of CX bikes, as well as the races. But you've got a point and I may have to resort to either just getting a roadie (which I would be happy with as well), or going the route you mentioned with the mtb frame and all that.
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