Machine Work

IMG_4605Apparatus is primarily about machine work that is the foundation for any project. Valve train geometry, bearing clearances, bore sizing and finish are fundamental and crucial to the success of any engine build. We have a wide array of calibrated inspection tooling, incuding bore gages, micrometers, and specialty tooling, as well as access to a CMM.  Most of the vintage bike shop manuals are woefully short on concrete data other than “assembly is the reverse order of disassembly” or an exploded view.  We take a common sense approach to inspection:  On a set of British cases the left and right main bores need to be not only the correct size, but also in the same plane axially and radially. The list goes on.  Simple stuff that makes the difference between something that lasts, and something less.

Cylinder boring–we use a Rottler boring bar specifically set up for motorcycle cylinders. Reboring and sleeving is done from the reference surface that sets bore/crank alignment and torque plates are used where appropriate.

Honing–a variety of Sunnen honing mandrels and abrasives are used along with flex hones when ultrafine finishes are required. Plateau honing with the correct crosshatch pattern is critical to proper ring seal. Cylinders have at least .003″ stock removed by honing to insure that all fractured metal generated by the boring process is removed.

Cylinder Head work–This covers a wide spectrum, and is often complicated by previous butchery!  The basics can be summed up in one word: Geometry. All of our valve train work takes into account rocker geometry, stem height, seat sealing and configuration, and proper guide finish and clearance. Our basic machine for this work is a specially fixtured Bridgeport set up to cut seats as well as rebore seat pockets, sleeve guide bores and flycut head gasket surfaces.

Case Work.—Weld repair, machining for oversize sleeves, thread repair, inspection, bearing bore repair as required.



Contact Apparatus MC

Apparatus Mechanical Classics, LLC
© 2014
214 E. 3rd Street
Winona, MN 55987