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clearances appear quite generous
by eye, would think there would be plenty of room to go to 700 wheel size - 622
you would of course wish to measure first
another check would be to see if there is enough travel in the brake pad adjustment to go with the 700 wheel size
if not, the 730 model calipers could be exchanged for a set of the 500 model
have owned Steyr tenspeeds which came with 27" wheels and model 500 brakes
it appears that the large clearances might allow you to go as large as 38c for tyre size. this would be great if you would like to be able to ride the bicycle on dirt/gravel roads & paths
wonder if perhaps the european version of this model would have come with 700 wheels and the 26" is something done for Sears...
shall look forward to following along as you work with the bike
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