I would agree with both points but here's some clarification.
42 inner is commonly run because it is already there and doesn't take any additional effort or money. If someone actually makes a conscious decision to run something else, they will usually opt for something larger, as Galen has described.
Today, more and more people are doing the latter. I run 46x16 on all my fixed geared bicycles.
Mark Buswell San Francisco, CA USA
On Oct 5, 2007, at 8:57 PM, dima wrote:
> Hi,
>
> Friday, October 5, 2007, 10:43:56 PM, galen pewtherer wrote:
>
>> As for the small chainwheel, typical sizes for everyday riding and
>> commuting tend to span the range from about 44t to 49t and with cogs
>> in the 16t - 19t range being typical.
>
> Actually, I think quite a lot of fixed "conversions" use the inner
> ring
> of the pre-conversion double, which is typically an even smaller 42t
> (paired with a 14-16t cog).
>
> --
> Cheers #1 today,
> Dmitry Yaitskov,
> Toronto, Canada.