Grizak

My Feedback: (3)

Hi everyone,

I know that this will vary from engine to engine and plane to plane, but in general what do you consider a good idle RPM for a gas engine?

Thanks,

Grizak

Bass1

Too many variables but on my 50cc aerobatic models on a (Grass surface), I'm happy with 1600 to 1750 rpm.

dirtybird

My Feedback: (5)

When the airplane does not move

Tired Old Man

My Feedback: (1)

I fly off pavement mostly but those numbers above work pretty well. Whatever the count is where the plane does not roll on flat ground is what works for me.

ram3500-RCU

My Feedback: (221)

I have a ground/landing idle and a flight idle that is 6 or 7 hundred RPMs more. My ground idle is just what others have stated. I fly off grass as well so at idle the plane doesn't move.

Bass1

If I have a 12 to 17+ knot headwind, I 'm "plenty" happy with a 2000 rpm idle though![8D]

MikeEast

My Feedback: (3)

Typical is probably 1600-1800 RPMs. For me too, as low as it takes to stop the plane from rolling on the ground and the engine does not die when it unloads in the air on final approach. I actually like a little bit higher idle in the air, maybe 2100-2400 rpms just to give more prop wash for the rudder in stall turns. To land you probably need to be able to unload the engine and idle back to 1600-1800. I am using the term unload to mean that last little bit of RPM drop that you get as the plane slows on approach and the engine reaches the lowest RPM you get just before landing. My BME engine is a little harder to unload and sometimes I have to pop the nose up sharply on final to get it to idle down and then its fine. Most of the other engines do it on their own,

captinjohn

MikeEast: Very good expanation. Also one may consider a idle speed that is low in vibes! Capt,n

krayzc-RCU

My Feedback: (31)

1500 rpm has fitted my needs for most of my 50cc or above gassers.