Another method of measuring the wheel circumference is to do it manually 
rather than use the given measurements in the manual. I too find them not to 
be inaccurate. First put your bike on a smooth surface. Mark the side of the 
tire with pencil or marker. Roll the bike forward until the marking returns 
to its origina position. Measure the distance the tire had travelled and this 
will give you an accurate circumference. Note: Make sure your tire is 
inflated to the proper pressure. I'm not sure if this would give a better 
reading, but perhaps being on the bike while rolling forward will be more 
accurate. Weight may have an affect.
Richard G.
--- Maximus/2 3.01
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