touring wheel size questions
 

What are the major determining factors behind the choosing a 700C over a 26" wheel for road touring? I have heard a lot of argument pro and con, mostly related to the standover height of a 26"-wheeled bike and therefore the ability to accomodate shorter riders. This is not a factor that would affect me but am curious what the advantages/disadvantages are from a mechanical point of view.

Is there a noticeable difference in wheel strength due to the smaller diameter?

How does the reduced diameter affect one's mileage or is this so minimal as to be inconsequential?

Also, it seems that bikes on a 26" platform are sized a bit smaller for a given rider than if the bike was for 700C wheels. Is this a fair observation and, if so, is this a factor worth considering as it pertains to frame stress under load as a smaller frame usually has less flex?

Thanks in advance for the feedback. The results will in fact be a contributor to the final decision...BLT or BLT-X.

Regards,
Don Johnson

Hi,
what is more important is the question that asks..... which of those two will suit you best? I would imagine Bruce Gordan would be the person to ask that question. Don't get hung up in the details, I would be more interested in refining the component choices to reflect my needs. And perhaps the best place to do that is on the wheels; after you've choosen the model. If you're heavy, and hard on gear, you might want to pick a heavier rim. If you are a 140 lb flyweight who plans on doing credit card touring; a light rim might be a better choice.

What are your intentions for touring?

Differences?

Given equal bikes, like the Bruce Gordon, the Atlantis or the Heron Touring, which are available in both wheel sizes, there isn't that much. Still:

- A 26" wheel is a bit stronger. A 36-spoke 700c wheel compares roughly to a 34-spoke 26" wheel... which means that a 32-spoke 26" wheel is weaker, but a 36-spoke 26" wheel is stronger than a 36-spoke 700c wheel.

- 26" tires are available all around the world... but I have also read that the 26" format may be different in India or Viet Nam from what we use here. IOW, not really a factor in North America or in Europe, but it might be in other countries.

- 26" tires are available in different widths. However, anything narrower than 26" x 1.5" might be really hard to find on the road. Fat tires, MTB style, are easy to find, however.
- 700c tires are available in different widths up to 47 or even 55 mm. However, you might have a hard time to find anything wider than 28 mm in small shops, and 32 or 37 mm in most LBS... so if most of your rides are on gravel or mud roads, 26" might be the best, but if most of them are on good packed gravel, stone dust or asphalt, than 700c might be better.

Wheel diametre vs mileage

St. John's Street Cycles in U.K., at http://www.sjscycles.com, has a whole article on the benefits of 26" tires. Not sure that I buy all of that. Still, overall wheel diametre also depends on tire size, and if you adapt gearing to actual tire size, wheel size doesn't really matter.

Frames for 26" are usually in the compact style with a sloping top tube , which makes them a little stiffer and lighter. There is no difference in the layout of the points of contact (bars, pedal, saddle).
I think tyre availability favours 26" over 700c in many parts of the world.
There is little to chose in terms of efficiency, if you use tyres of comparable pressure.