re: 60 MPH...achieveable? Who cares?!? Let blueprint an engine!
This is a multi-part post that will describe in detail the first step that is necessary in order to blueprint one of these engines.
Match and dowel pin the cases.
These engines do not have a "positive" register that ensures perfect bearing alignment. In the interest of H.P., reliability, and attaining a high R.P.M. the bearings must be perfectly aligned. If I can't get this engine to spin up, there will be no chance of making the bike go fast.
The first photo shows the cases finished, the case half mating surfaces have been machined square to the bearings and three dowel pins have been installed to ensure perfect bearing alignment . I used 3/16" dowel pins. One case half has dowel pin holes that are .1865 in diameter for a press fit of the dowel pins. The other case half has holes that are .1885 in diameter for a slip fit of the dowel pins. Precision reamers were used to make the hole sizes accurate.
The second photo shows the case halves with hardened and ground Meyer gauge pins inserted into the bearings in one half of the case. I have meyer super precision gauge pins from .011"-.750" in .001" increments. The I.D. of the bearings is 15mm, which is .5905". The gauge pin in the crank bearing is .590", the pin in the countershaft bearing is .589".
The third photo shows the cases mated together. The dowel pins were a perfect slip fit, with no movement of the case halves.
The final test, "the feel of the gauge pins". The .590" pin in the crank bearings floats left to right with the slightest touch. The .589" gauge pin in the countershaft bearings passes through and falls out if the cases are tilted even slighty from what would be the normal upright position...as though installed in a bike.
The cases are perfectly aligned...and pinned, ensuring repeatability.