700c -> 650c on a Road Bike

[JoHunter]

Hi everyone, I've just bought a very small road bike frame and had it fitted with standard parts to get me going. However when I saw the 700c wheels on it it's definitely all out of proportion. I'm worried that I might have a bit of toe overlap and would like to put some 650c wheels on it instead. Does this mean that I will have to change the fork as well? Or are there brake levers that will be able to reach it that extra bit further. Also I have the 170mm cranks and have heard horror stories of pedals scraping the ground when using smaller wheels. Fact or Wivestale? Thanks a lot!

[SadieKate]

Why did you buy this bike if you don't like 700 wheels? Frames and fork are designed to be ridden with certain wheel size. Brakes won't fit, fork rake will be wrong, BB god only knows, I'm not an engineer. I've never heard of any adaptors to make brakes work.

I don't think I have one bike that doesn't have toe overlap. I've never had a problem, you just need to be aware of it. Didn't you determine overlap before you bought the bike?

[fixedgeargirl]

However when I saw the 700c wheels on it it's definitely all out of proportion.

Forget how it looks, does it function?

[Grog]

However when I saw the 700c wheels on it it's definitely all out of proportion.

What do you mean by "out of proportion"???

I have a very tiny frame and the wheels _do_ look very big on it. It _looks_ out of proportion, but it's correctly sized anyway.

I think you should be a bike fit with a professional at a reputable bike shop. But it is certain that your current fork, if it is made for 700 wheels, will not take 650 wheels.

[Running Mommy]

I have a size 44 Specialized w/ 700's on it and it rides fine. I don't know what you mean by "toe overlap" but I've never noticed a problem. I guess when I look closer at my bike I can see how the wheels look bigger, but it doesn't bother me. Though My new tri bike will prolly have 650's on it as thats what the smaller frame sizes come with.

[kiwi girl]

You say you are worried about toe overlap - but have you actually checked if it is an issue. I'm 5'1" and yeah both road bikes I've had look out of proportion - not wanting to offend anybody but I refer to them as mutant dwarf bikes - but I think that is part of their charm. I haven't had a problem with toe overlap.

[JoHunter]

Hi everyone thanks for the replies. I was unable to judge the toe overlap on this bike prior because it is a custom made frame (not for me, a second hand one I found in my size). My LBS was willing to fit it with standard parts. I wasn't sure if the fork of the bike was to accomodate 700c or 650c wheels. Now that I actually have it with the 700cs there is a bit of overlap. Depending how I turn it my toes clip the front wheel, so I have to be a bit careful with it. I may end up getting shorter cranks that might help. From various different sources I found that a lot of people recommended the 650c wheels for shorter people to help with acceleration and climbing hills. I have heard of people turning their road bikes into tri-bikes and wondered if they bought new forks or found long-reach brakes.

Actually thinking it about it now, it is very odd that a custom built frame would have the toe overlap problem. I would think most small frames that were made to accomodate larger wheels would make the effort to avoid it.

[fixedgeargirl]

I was doing some investigating re: crank length yesterday. I learned that a longer crank length allows for better leverage but dictates a lower cadence. Better for power on an off-road machine. Shorter cranks allow a quicker cadence, better spin and don't require the knee to achieve as intense an angle (SAVE THE KNEES !)

I also came across some calculations vis a vis crank length as a percentage of femur length. Can't find the link now, but the gist of it is that even 165s can be *too long* for a petite woman. But then there's the study Sheldon Brown links to regarding wattages produced using different crank lenths (from 120-220 I believe) with the greatest wattages being produced using the mid-range cranks.So much information, is that smoke coming out of my ears.... ?

Anyhoo, I'm 5'3", 27" inseam, on a custom frame with 165 cranks. Have 165s on all my bikes and feel loss of power and sad knees on anything longer. Shorter cranks might benefit you in many ways, including eliminating the overlap issue.

[SadieKate]

Depending how I turn it my toes clip the front wheel, so I have to be a bit careful with it.

Is this when you are riding or when you are standing in the parking lot with one foot clipped in?

[Kathi]

Hi everyone thanks for the replies. I was unable to judge the toe overlap on this bike prior because it is a custom made frame (not for me, a second hand one I found in my size). My LBS was willing to fit it with standard parts. I wasn't sure if the fork of the bike was to accomodate 700c or 650c wheels. Now that I actually have it with the 700cs there is a bit of overlap. Depending how I turn it my toes clip the front wheel, so I have to be a bit careful with it. I may end up getting shorter cranks that might help. From various different sources I found that a lot of people recommended the 650c wheels for shorter people to help with acceleration and climbing hills. I have heard of people turning their road bikes into tri-bikes and wondered if they bought new forks or found long-reach brakes.

Actually thinking it about it now, it is very odd that a custom built frame would have the toe overlap problem. I would think most small frames that were made to accomodate larger wheels would make the effort to avoid it.

It's not so odd having toe overlap on a small frame with 700c wheels. It depends on who made the frame and what material it is. I'm planning on building a custom frame and I was working with a well known company that does custom build. I'm looking at a ti or ti/carbon combination. The frame I wanted is only available with 700c wheels because the company doesn't make a carbon or ti rear triangle small enough for 650c wheels. So I would have a 44cm frame on 700c wheels plus the spot where the tt and rear triangle meet wouldn't match up. Also, I would have 1cm of toe overlap.

Since there are other companies that can do small frames with 650's I nixed this design.