On 9/21/2011 3:08 PM, HeyBub wrote:
....

... PTOs are (I think) fairly standardized...

_Very_ much so...540 (6-spline) and 1000 (21-spline) rpm are US
standards; virtually all larger tractors now have both as standard
equipment (interchangeable spindles, not two separate drives); smaller
utility tractors of the homeowner variety will generally be limited to
540 rpm.

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