Old 05-17-13, 07:01 AM
  #8  
Doug Fattic 
framebuilder
 
Join Date: Dec 2009
Location: Niles, Michigan
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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.
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