Heres a rare one.  The transmisssion for a 1941 Harley-Davidson TA -- better known as the Shaft-drive Knucklehead Trike.  This thing is an absolute monster.....HD spared no effort in designing the beefiest transmission they could.  Notice the wider transmission case, and angle-cut gears to mesh the shaft-drive output.  The "EX" casting on the top indicates that its an experimental part right out of the Harley-Davidson engineering department. 

Kind of funny how the shift crossover is on the right side.....Then I got to looking at the factory photographs....and most of the TA's were right hand shift.  The example here at the museum -- the Canadian serial #1 prototype -- has the normal left hand shift and a crossover on the rear motor mount.

The transmission takes a standard knucklehead kicker cover, and a stock clutch basket.  I think this one is also up for the "Worlds Shortest Drive-shaft". 

The shiny gear pictured is a brand new reverse gear for this set up.  In the second picture it gives you a good idea of how rusty and crusty the inside of the transmission is. 

This transmission will be going in Serial #3 out of the 17 built by Harley-Davidson in 1941.  Check it out in the military exhibit next time you're visiting.