dpb wrote:
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.

Come to think on it, why don't devices with smaller engines have a PTO?

I could imagine a PTO on a lawnmower and a raft of attachements:
* Brush cutter
* Generator
* Black water pump
* Drain snake
* ???