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-   -   Finding a framebuilder, I need a very, very small road frame. (https://www.bikeforums.net/framebuilders/889991-finding-framebuilder-i-need-very-very-small-road-frame.html)

nerobro 05-16-13 01:05 AM

Finding a framebuilder, I need a very, very small road frame.
 
So, I"m at at loss for getting a bike that will work for the woman in my life. She's 4'8". She also loves what a carbon fork, and 700c wheels do for the bike she's riding.

Right now we have her on a 42cm frame. We really need something more like a 34cm frame.

From what I can tell, the only way to get 700c wheels, and a 34cm frame, and hopefully a low BB as well, will need someone with a Tig welder, and some tubing.

So, how would I find a framebuilder? Are you one? Would you like an interesting project? :-)

Thanks everyone.

ftwelder 05-16-13 03:19 AM

Many of us are frame builders. I do TIG frames and often very large or small ones. The usual limitation for small people and 700c wheels is toe contact with the front wheel. If she is riding a 42 now, isn't hitting toes (or doesn't mind) additional stand-over clearance should be easy. We can certainly discuss potential options. My email is below.

Also, some other builders are able to make lugs that offer unique angles and solutions so lugs are an option!

ksisler 05-16-13 08:00 AM

OP: I have noticed that Mr Rodriguez (www.rodbikes.com) specializes in very small bikes and in bikes for ladies (including hardcore racers, down hillers, etc.). He has photos posted there of examples also. Recommend reading the background info on his site to see if it helps.

bikemig 05-16-13 08:13 AM

A custom frame builder makes sense for your needs. You will want to consider whether to stick with 700c wheels as that requires some compromises on a small frame but a builder will give you the pros and cons. Soma, for example, makes a 42 cm mixte frame that takes 26 inch wheels that you may like: http://www.somafab.com/archives/product/buena-vista

Brian25 05-16-13 09:28 AM

Would your wife be interested in a light aluminum frame (about 2.5 lbs) with an internal (integrated) headset and a carbon fork? I've built bikes as small as 30cm, and could design a small bike based on her measurements and preferences. You can check out www.ravellobikes.com . I can also build a steel frame if she prefers that.

GrayJay 05-16-13 11:44 AM

At that small of a frame size, 650c wheels make a lot of sense for reducing toe/wheel interference, keeping the TT short while retaining a resonably handeling head tube angle and for getting the headtube low enough for an aggressivly low handlebar position. A 700c wheel and the shortest possible headtube still will likely push the stem/bars upward too high to get good drop from the saddle height.

Andrew R Stewart 05-16-13 10:21 PM

Agreed that smaller wheels make sense for a small rider. How small depends on how the design needs add up. One of the pitfalls of this issue is that each builder has solved their challenges with a certain approach. What I've read in the replies makes me think that no one has yet seen the answer. 4'8" is very small. I'm surprised that 700c wheels have been found to work well. The rider needs to explore and ride bikes with 650c and 520ISO wheels for long enough to know what feels best. Andy.

Doug Fattic 05-17-13 07:01 AM

I've made a lot of frames for women in my years and I don't believe there is any way someone as short as 4'8" can come close to an optimum custom frame using two 700c wheels. If you guys came to me to get a frame I'd say obsoletely no way would I compromise the design so much as to make that work. I would do everything in my power to explain why smaller wheels are a much better option. In my opinion, the custom design should begin by finding (or reaffirming) her bicycle contact points typically defined as saddle height, setback, handlebar reach and drop. Once that is established, the frame tubes can drawn in to connect those points. It is obvious to me and eventually it should be to you and her that a 700C wheel will put her handlebars too high compared to her seat (unless it is a very upright handlebar design like a beach cruiser) and you will have severe toe overlap with the front wheel. You won't have either of those disadvantages with smaller wheels.

For starters, smaller wheels look more proportional on a small frame. You don't have a super short head tube on top of big looking wheels or the top tube coming into the down tube to get it lower. Second of all smaller wheels are lighter and thereby faster. I know, I've made bikes myself with both 650C and 600 (24") wheels. The 24" wheel model was for a travel bike that take up less space. The difference in gearing is one tooth on the rear cog for 650 bikes and 2 for 600. In other words going to a 12 or 11 instead of a 13.

It is also possible to use the old Terry design of a 27" back wheel combined with a 24" front wheel. The disadvantage is that it requires carrying 2 sizes of tubes. Her company still carries a 600 X 28 tire. On my travel bike I use 24" X 1". They are similar to a 25. The only reason to do it that way would be because she will prefer the way it looks. When I've made frames for women as small as your partner's I've used two 24" wheels. I'm betting even two 650C tires are a bit much. By the way it is possible to make a frame so that with short reach brakes it can use 650C tires and with long reach brakes, MTB (559 bead diameter) tires. I did that for my 5'3" daughter.

Mark Kelly 05-17-13 07:26 AM

+1 to Doug's comments. My son's girlfriend is 138 cm (about the same as your wife), we recently put her on a new 600 wheeled bike and she loves it (though she's a long way from a "serious" cyclist). I could not see any way of fitting her to a 700C wheeled bike that didn't suck.

ksisler 05-17-13 09:24 AM

OP: The several suggestion on going with a smaller wheel fully agree with my experience also. I will add:

1) In the cases when a large diameter wheel is used on a small frame, the physics seem to not be right. By this I mean that when a wheel/tire spins, its mass has a lot of centrifugal force that affects the bike and its rider. It seems that the amount is about right when a large wheel is used on a large bike and about right when a small wheel is used on a small bike. Some will categorize the effect as being one of the wheel attempting to steer the bike or to resist the riders effort to steer the bike. Sort of becomes a bit of a fight between the rider and the bike.
2) The other aspect is that the weight of the rim and tire/tube has to be rotated around the axle by the riders muscles. When the rim/tire/tube is disproportionally far away from the axle for a respective frame size, then the amount of work the rider must do is also equivalently disproportional.
3) Most riders have a vision of what a good bike looks like to them. In my view, when one steps back 10 feet from any bike, it should not be notable whether it is a large/large or a small/small. When the wheels used are out of proportion to the frame size...well it just looks goofy and draws negative attention... often along the lines of questions like "when are you going to trade that in for one that fits you?" Ouch!
/K

Shimagnolo 05-17-13 09:33 AM

1 Attachment(s)

Originally Posted by bikemig (Post 15631713)
A custom frame builder makes sense for your needs. You will want to consider whether to stick with 700c wheels as that requires some compromises on a small frame but a builder will give you the pros and cons. Soma, for example, makes a 42 cm mixte frame that takes 26 inch wheels that you may like: http://www.somafab.com/archives/product/buena-vista

Here is a 42cm Buena Vista I built as a road bike for a 5'3" female.
Tires are 26" x 1.25" slicks.
Seatpost is set for her calculated saddle height.
She hadn't picked it up yet, and was bringing her own saddle.

Bike on right is a 62cm Soma Doublecross with 700c wheels.

David Tollefson 05-17-13 02:23 PM

Also note that you'd want to build the front end around some very short/shallow handlebars. Going "standard" with the bar reach is just going to make the front end that much more difficult to design.

Rosa7 05-19-13 03:58 PM

Nerobro, I'm 4'8" with an inseam of 25". I would like to find a decent road bike that I could also use for touring, and I don't think I can afford a custom bike. In any case, I would love to hear your final solution for your gf. Also, if you are interested in selling her current 42cm bike, please let me know, especially if the standover is less than 28". I'm a newbie, so I can't contact you, but feel free to send me a private email.

ksisler 05-20-13 08:48 AM


Originally Posted by Shimagnolo (Post 15636077)
Here is a 42cm Buena Vista I built as a road bike for a 5'3" female.
Tires are 26" x 1.25" slicks.
Seatpost is set for her calculated saddle height. She hadn't picked it up yet, and was bringing her own saddle. Bike on right is a 62cm Soma Doublecross with 700c wheels.

Shimagnolo; I think your photo exactly demostrates a point I was trying to make; The perfect portionality of the wheel and bike. If we were to move those bikes 15 feet apart and take another photo, it would not be noticable that one is much larger or smaller than the other. They both just look right -- perfect.

/K
PS: And that Mixte will probably be an awesome rider...but I have a weakness for them stemming from back in the early 70's having had some nice French mixte singles and tandems and never got over it.


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