Hi,
I have a new Magnum .52 that is just barely broken in - about 1.5
hours of run time. I am running a 12x5 prop and only getting about
8900 RPM, Fuel is good, idles ok, does smoke some in the transition
but don't want to lean it out too much. Is this prop too aggressive?
I am supposed to be getting about 11,500 to 12,000.
Any suggestions to improve the low RPM at the high end?
Thanks,
Bob
--------------------------------------------------------------------------------
Straight from the instructions...... 11x7,8,9: 12x5,6,7; 13x4 ! I' m
running a 12x6 TF Power Prop on mine on my 71" Cub and it works fine -
IIRC it spins about 9300 on 10% nitro and it's got about 2 hours time
on it.. That Magnum will free up some more as you get more time on
it. You did not spec the %nitro, so the rpm may or may not be OK.
That 11500 to 12000 is probably with 11x7 or 12x5. Don't worry so
much about rpm, just 'does it fly your plane OK' ? I've got a Magnum
61 FS turning an 11x7 3 blade at only 9800 rpm, and it pulls my 6.5lb
SPAD Debonair aroung quite nicely.
David
Mine depends upon the plane. Probably due to weight.
I had a 12x5 on it while flying a Magic 3D. Loads of power. Pulled out
of hover with authority.
Now motor is on a Magic Extra. I found 11x6 best so far. The 12x5 did
not seem to do well. I did pick up a 13x4 wood the other day - will
try that.
I know of others runnig 11x7 and 12x6 and are happy. One guy has a
12x7 in a Kadet.
BTW - adjust the valves. Mine needed adjusting after less than a
gallon.
Mark
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.