Your engine is a lot older than the ones in the pic above. The above pics have standard carburators with intake valve operated by camshaft.
Your engine appears to have an atmospheric operated intake valve( no intake camshaft) and a mixer carburator common to older type engines.
Not nearly as much power and rpm to deal with as the newer versions.
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The little pully was prolly to run a small generator for lights on the motorcycle.
I don't know what you paid, but with some info and the right listing might get you couple thousand bucks for it.
If you wanted pedals- Why not? They could be your foot pegs
Here’s a wheel visual for you...
A vintage 26” bicycle wheel, a aluminum 21 x 1.60 DID rim (Honda) and a 21 x 3 wheel (Yamaha) with drum brake.
I’m going to lace that monster hub into the aluminum rim.
-Kirk
That was a good score!
I’m Jealous.
Here’s another reference...
http://www.google.com/imgres?q=mode...&w=625&h=456&ei=CSkrT-H9DMvy2gXX--mEBA&zoom=1
-Kirk