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Roger Derby
 
Posts: n/a
Default Anybody ever converted a lawnmower or dirtbike engine to a inboard shaft and propeller setup?

Horsepower is the rate of doing work. Why is it surprising that a small
force at high speed is different than a large force at low speed? It's how
the small displacement car engines at 9,000 rpm are able to compete.

Roger

http://home.earthlink.net/~derbyrm

"Brian Whatcott" wrote in message
...
On 30 Oct 2005 13:20:29 -0800, "rvbilly" wrote:

Hi, I am not following what you mean with with the thrust bearing, and
what would be the advantage of the reduction gear? thanks Bill


It is a strange thing when you first hear of it: but the same HP can
give a few pounds of thrust at high boat speeds and hundreds of pounds
of thrust at slow speeds.
The latter place is where marine transmissions live - so they need
buff thrust bearings if they are to last any time at all.
Water props get inefficient at high speeds.

Brian Whatcott Altus OK