Vibration Comparison RCV Cd Vs other 4 strokes
#1
Junior Member
Thread Starter
Join Date: Jun 2008
Location: Melbourne, , AUSTRALIA
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts

Hi, just wondering of anyone could provide some vibration comparison opinions on the RCV CD motors and other 4 strokes, or even the RCV SP for that matter.
The reason I ask is that I am putting together a UAV project and need a motor with the lowest possible vibration.
Until now I have been going to use a Saito 150 but the midrange vibration is more than my electronics can handle.
I was wondering (hoping) that an RCV130 CD would be considerably less vibration.
I would be very interested to hear of peoples experiences with this engine, or even opinions from the experts as to how these engines fare.
Thanks,
R.
The reason I ask is that I am putting together a UAV project and need a motor with the lowest possible vibration.
Until now I have been going to use a Saito 150 but the midrange vibration is more than my electronics can handle.
I was wondering (hoping) that an RCV130 CD would be considerably less vibration.
I would be very interested to hear of peoples experiences with this engine, or even opinions from the experts as to how these engines fare.
Thanks,
R.
#2
Junior Member
Join Date: Dec 2008
Location: Dorset, UNITED KINGDOM
Posts: 18
Likes: 0
Received 0 Likes
on
0 Posts

Hi
My name is Keith Lawes, technical director at RCV.
Obviously would be easy to promise that the RCV CD range are the smoothest devices known to man, but to be honest all single cylinder 4 strokes are going to be very much of a muchness, whichever one you select.
With a single the main dictator of vibration level will be capacity. This is partly mechanical out of balance forces (as you cannot fully balance the reciprocating piston with a rotating counterweight on the crank) and partly due to the torque pulses from the firings (negative torque during compression followed by positive torque during firing, the difference between the two being the net torque output). Both of these will increase pretty much linearly with capacity. Twice the capacity, twice the vibes.
So the Saito 150 would prob have more vibe than the RCV 130CD. But of course it would also have significantly more power. If the 150 defeats your electronics its unlikely the reduction in vibe from the 130 would give you any safety margin.
Prob the best route forward is a boxer twin. This has near perfect balance forces, and much smaller torque pulses for a given capacity. This is why this is the most common configuration for UAVs.
Incidentally we do have UAV boxer twins under development, specifically designed to run on heavy fuel (JP8 or kerosne). They are pre-prototype and v expensive!! Prob your best bet would be a Saito or OS unless you have a definite heavy fuel requirement.
Hope this helps. If you have any specific enquiries maybe you could contact me on [email protected]
Regards
Keith
My name is Keith Lawes, technical director at RCV.
Obviously would be easy to promise that the RCV CD range are the smoothest devices known to man, but to be honest all single cylinder 4 strokes are going to be very much of a muchness, whichever one you select.
With a single the main dictator of vibration level will be capacity. This is partly mechanical out of balance forces (as you cannot fully balance the reciprocating piston with a rotating counterweight on the crank) and partly due to the torque pulses from the firings (negative torque during compression followed by positive torque during firing, the difference between the two being the net torque output). Both of these will increase pretty much linearly with capacity. Twice the capacity, twice the vibes.
So the Saito 150 would prob have more vibe than the RCV 130CD. But of course it would also have significantly more power. If the 150 defeats your electronics its unlikely the reduction in vibe from the 130 would give you any safety margin.
Prob the best route forward is a boxer twin. This has near perfect balance forces, and much smaller torque pulses for a given capacity. This is why this is the most common configuration for UAVs.
Incidentally we do have UAV boxer twins under development, specifically designed to run on heavy fuel (JP8 or kerosne). They are pre-prototype and v expensive!! Prob your best bet would be a Saito or OS unless you have a definite heavy fuel requirement.
Hope this helps. If you have any specific enquiries maybe you could contact me on [email protected]
Regards
Keith