I agree that a serial number would help with narrowing the date of your Colson-built bike.
In later 1933 and 1934, Colson had paperwork showing 26" balloon tire motorbikes.
Specifications list 7" cranks for the 28" bikes; 6+1/2" for the 26".
I find the 24-tooth chain rings, like yours, more convenient, with the moderate grades, maybe not so much for foothill areas.
I believe that there is even a bike club with a logo the resembles the Colson Flyer head badges.
I believe 2+3/16" badge holes, with screws, similar hole spacing as some Huffman and A&S bikes.
This is great documentation for these. I'm trying to figure out what my 34 would have looked like. I believe it would have come with 28 inch wheels since there's so much gap with the 26s currently on it. But I have not seen any examples of the 34 Colsons that didn't have 26 inch wheels. It seems that finding original parts for this one is more than tough and quite expensive.