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Old Oct 03, 2012, 12:29 PM
Luvmyhelis is offline
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Professional heli wrecker
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United States, WA, Spokane
Joined Oct 2010
4,478 Posts
Agreed about the motors. However I have only one mod where the 1811-2900s failed and that was when I added the larger BOL accra blades just to test. The motor heat was a limiting factor for sure. In fact it is the single most important limiting factor in outrunner motor design.

And I agree again with OlliW here. Dont run any pinions that thin the pinion wall out too far. Not only does it weaken the pinion but the gear spread actually wears the main gears out faster and produce more noise. I have run everything from 8 to 14t pinions.

On the Turnigy 1811 motors you simply must let them breathe. Once I opened up the canopy top to allow the trailing edge of the blades to waft air over the Turnigy motor cans it solved all my problems. (In fact this was the core of my own carbonfibre blade design was the introduction of the overlapping funtional blade root. It eliminated the dead grip area where there was no lift down the center area, and helped cool the electronics)
By letting the motor cans breathe, I could suddenly add the needed weight I needed to have for outdoor flying (to handle the wind) and to change the cog of the heli so it would bank correctly. As of yet I cannot outfly these simple cheap motors on 3s, and they are coming down barely warm. As are the Turnigy 10a esc's. And I am getting full 14min flight times out of mine and punishing it. Also once the weight was added, (mostly battery), it enabled the gyromixer to fully dial in the heli with the increased headspeed. One of the problems with the lighter 2s brushless CX3 setups is the blades are moving so slowly (especially with the high lift Xtremes) that there simply isn't enough blade torque/momentum being generated for any gyro to work at its optimum. Once blade speed was increased the added motor/drivetrain momentum allowed them to compensate much more quickly to gyro commands. But with fixed pitch blades I had to both change the blades and add weight and 3s power to achieve this. None of this would be truly possible without the advanced brushless mod.
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