OP's Name That Bike - 12 April - Plymouth Record Attempt Bike

[Otto Puzzell]

Know what it is?

Please, respond below and share your knowledge of what this is, and who built it.
As always, detailed answers are greatly appreciated by all. 
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Also, please be sure to check out our other puzzles, and, please post a puzzle of your own if you'd like - the more, the merrier.

Thanks!

[Otto Puzzell]

experts...

[white12]

It is the plymouth motorcycle