The Medium Gear (events)
Traditionally the first event of the year, after the Reliability 50 (now called the Burnham & Baddow Challenge) was the Medium Gear.
After a winter of club runs, for many on a fixed wheel, it was time to put that fitness to the test over a 25 miles time trial, again on a fixed wheel, or if using gears, with the sprockets screwed off, so the rider was not able to change up in to a larger gear. In both instances the gearing could not exceed 72 inches.
This month we look at four Medium Gear events from the late 70’s – early 80’s, which took place on the E31(A127).
What is a medium Gear? Using inches to measure gear sizes dates back to the days of the penny farthing, if it had a front wheel of 72" diameter it was said to have a gear of 72". On modern bicycles the gear size is calculated by multiplying the wheel diameter (in inches) by the number of teeth on the chainwheel and then dividing this by the number of teeth on the rear sprocket.
A 48 tooth chainring x 18 sprocket would give you a 72" gear on a 27 x 1.1/4" wheel. Appling this theory to a 700c or tubular would leave you somewhat under geared so a slightly larger chainring (49 tooth) would probably be a better choice and with smaller tyres a 52 x 19 may be possible. The only sure way to check your gear is to measure the distance travelled for one pedal revolution, for a medium gear this is 18ft 10.1/4 inches.
Now you know how to work what a Medium Gear is, next time you go out, try that configuration, or as near as you can get to it.
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