RE: R/C AIRPLANE PROPS
BY: Mark Corona to Neil Scavelli on Sun Dec 10 1995 08:26 pm
 > In a message of 09 Dec 95  12:36:12, Neil Scavelli wrote:
 > 
 > NS> Put an 8x6 on that OS 25 for optimum performance.. it should turn it
 > NS> somewhere
 > NS> around 16,000
 > 
 >     No.  Too fast.  If you turn 16,000 on the ground you will overspeed 
he
 > engine in the air.
 > 
 >     Unless it is a ducted fan engine it shouldn't turn over 13,000 on the
 > ground.  Even 13,000 is pushing it some.
 
I'm totally disagree with that.. if you have a .25 size engine and you Prop 
t
right it will run about 16.5 then you take off 500 by richening it. when it 
s
in the air its probably turning somewhere around 17+ Now this is for Racing
Pylone Quicky 500..  if you put too big of a prop on a motor and to get a .25
to not go over 13k your looking at a 9x5,9x6 in which case your not moving
enough air over the motor for that load and running it way to hot.. 
When running a Q500 racer your not making death dive runs on the motor.. it's
pulling the plane at a constant rate and hard in the turns.. so there is 
ever
a point where you will overspeed the motor... I am talking about a motor that
is rated by the manufacturer "practical RPM Range" 2,500 - 19,000 
If it's has ball Bearings and it's ABC or AAC it's going to run to its 
Optimum.
at that RPM rate with no problems.
if you run bushing engines that's another story. 
Neil S.
--- GEcho 1.00
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