Nearly 14 inches tall, 17.5 inches wide, and using some 10 square feet of plywood, this V-twin is inspired by the thundering Harley Davidson (R) engine from the late 50's.  Features a genuine rod and fork connecting rod arrangement, four separate functioning cams, and authentic valve action.  See the Kickstarter for videos and details. You may download the assembly instructions here.  (Note - these still have a few typos, and should be printed at 50% scale.)

Price - $150 per kit.

A video tour of the Assembly Manual

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