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British Bikes / A Tale of Two Gearboxes
« on: April 08, 2026, 09:58:05 PM »
I have a 1949 BSA B31. The gearbox is a mess so I got another hoping to use two to make one serviceable.
I've come up with a situation that I cannot find any information on.
In one gearbox the mainshaft gear (24-4231) slides on the shaft easily. In the other it took 5 tons of pressure to remove the gear from the shaft and if it goes back on, it will take a press to get it there. The easily moveable one will not slide on the other shaft either.
Question is: Which it correct?
Does the mainshaft gear move along the mainshaft in normal operation or is it supposed to be fixed and stationary during operation?
Many Thanks.
I've come up with a situation that I cannot find any information on.
In one gearbox the mainshaft gear (24-4231) slides on the shaft easily. In the other it took 5 tons of pressure to remove the gear from the shaft and if it goes back on, it will take a press to get it there. The easily moveable one will not slide on the other shaft either.
Question is: Which it correct?
Does the mainshaft gear move along the mainshaft in normal operation or is it supposed to be fixed and stationary during operation?
Many Thanks.