Author Topic: Crocker Speedway  (Read 2851 times)

Offline friday

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Re: Crocker Speedway
« Reply #15 on: August 29, 2023, 10:38:31 PM »
1931 and 1932 have 1930 specs.
Clymer became 'English Motorcycles' -'Clymer Motors in 1933.
George Wallis designed frames

Offline cardan

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Re: Crocker Speedway
« Reply #16 on: August 30, 2023, 05:09:59 AM »
1931 and 1932 have 1930 specs.

Rudge? The 1931 DT Rudge used a very different engine from the 1930 DT. It was based on the 1930 TT engine, so it had different crankcase, timing gears, cylinder, and head (with bolt-on plates rather than cast-in pillars to support the valve gear). Also for 1931 there was an option of the standard 1930-type frame, or a new longer wheelbase version. Despite the fab new engine, even Rudge greats were bolting JAP engines into their Rudges after the first few races of the 1931 UK season - the origin of Victor Martin's "Martin JAP". I see that Martin's early brochures noted that the frames were made "Under Licence with Rudge Whitworth Ltd" - interesting that Martin and Wallis/Comerford ended up under the same umbrella.

I wonder why the Crocker DT machine ended up with a cross-over gearbox. Seems like such a bad idea on paper.

Leon

Offline john.k

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Re: Crocker Speedway
« Reply #17 on: August 30, 2023, 06:42:18 AM »
Cross over was pretty standard US racing practice.....the final drive ratio could be changed in a few minutes.

Offline cardan

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Re: Crocker Speedway
« Reply #18 on: August 30, 2023, 11:55:36 PM »
Good point - maybe that's the reason. With a massive amount of power from the speedway engine the price is the chains yanking the countershaft in opposite directions at each end.

Leon