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fitenfyr
08-08-2005, 11:57 PM
Ok I have this headspeed related problem I can't noodle out.
When I have the Gasser in a hover I get this up and down "bouncing" almost like a ground resonance, but in the air.
It does it on the ground just before lift off, but that I know is resonance and soon as I lift off it gets better.
It also seems to increase when I make a cyclic input.
It was real bad at the higher headspeed (I don't have a tach to tell you the numbers), but after I turned the throttle curve down about 10% it got better, but not gone.

The servos are 4131 JR's and are in good shape. The control linkages are tight and not binding.
I am using a 9Z (ah that must be it..The JR servo's are rebelling against their leader. :D ) and cannot find any mix or anything that is causing it.
I have checked the mainshaft and it is tight in the collars.
The only thing I can think of is the dampeners. They feel pretty loose to me although they have seen little flight time.

I will try and get a video up of what it is doing in a couple days.
BTW my throttle curve is at 0-30-80 and the motor seems to be happy in fact I richened it up an 1/8th turn on the low end tonight due to the increased temps we have been having.

Any ideas?

cbergen
08-09-2005, 09:42 AM
Is it possible the 4131 isn't strong enough on collective???? Typically we recommend a 4721 in that spot.

fitenfyr
08-09-2005, 12:01 PM
Ok that was a thought also.
It has never been an issue until now. Course that servo could be just now worn to the point of causing it.

fitenfyr
09-07-2005, 12:45 AM
Ok Chris was correct again...:D
Geesh I have got to stop doing this his head is going to get bigger and bigger, and......:D

Installed a new Digital Hitec monster stump pulling metal gear servo and the bouncing stopped. :D

Now the other 4131's are going away and 9252's are going in for cyclic control.

cbergen
09-07-2005, 10:09 AM
:noteworthy