The torsional resonant point is highly dependant on how smoothly the engine
idles. If you have no misfires, the RD-1C hits resonance at around 800
rpm. If you have any misses at idle, this immediately introduces a much
higher amplitude and lower frequency excitation to the system and it will show
up at a higher rpm.
In summary, the "rattle point" is more dependant on idle quality than
absolute rpm. Do not be too concerned about this however. It
will cause no harm to the drive or engine. The drive has been torture
tested for over an hour running on one rotor over the full range of throttle
settings. If you've ever run a twin rotary on one rotor, you know how
violent this is. George Graham ran his Mazda transmission redrive on one
rotor for about 2 seconds before every gear tooth on one gear was stripped
off.
Tracy (now canoeing to the post office one last time before
departing for S'nF)
Greetings,
I asked this a couple
times, but it was always buried at the end of long messages, which gives me a
clue how few people make it to the end of those :-)
IIRC, the RD1 drives have
a low rpm point where they're known to rattle. I guess this is
torque reversals, or something like that from the engine. Anyway, can
someone confirm that this is true, and tell me what rpm this is supposed to
happen at? I've never been able to idle below 1500 or so, but now, I
could probably idle down to 1000 easily. The problem is that I seem to
hit this rattle mode at 1100-1200 rpm, so I've got my idle set at 1400 for
now.
Thanks,
Rusty (wondering if I
should have inspected the redrive following the oil out)
PS- TIG and Plasma
machines both got 1.5 inches of water before I picked them up, but I dried
them out yesterday, and they both work now (thank goodness).
Fortunately nothing expensive was damaged in the flood, assuming we don't have
to replace the carpet in the great
room.