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airhead BMW rotor

will the center of an airhead rotor press out from the windings? I want to use the center part to mount a pulley for external alternator. Jon

I made a long reply to the general discussion threads to answer so I won't here. Read the general discussion 'auto alternator' for details.
Quite simply, NO,
the center will not press through. Instead the outer hex-fingers come off in opposite diections.

Seems odd that no one else here has ever tried to do it( and tell about it ). ................electrifying.............ha.

Well, now I know . The iron outer fields are fairly easily bumped off from either end. They are on small lock splines. The center of the shaft with the copper windings is greater diameter than the ends of the shaft. So, the iron field ends will not press through. They must come off the ends in opposite directions. Using puller is likely a more satisfactory way to get them off since hammering on them can result in warping the inner taper that fits onto the crankshaft. It worked for me.

I had the center portion turned down to 1 1/8 inch for mounting a 3.75 pulley sheave for the external alternator. Will do pics when finished
for those interested including brackets, shaft and all. Jon