Rotor Blades
The model flies nicely with 700mm blades. The stock configuration can support up to 720mm blades with no modification and there is
an optional conversion kit available to allow the use of 750-810mm blades. Keep in mind that the std 6.88 gear ratio was designed for
use with a 26cc engine and 700mm blades. If using a 29cc engine 710mm to 720mm blades work fine with std 6.88 gear ratio.
Pitch Curves
Set up your pitch curves as you normally would. With stock motors and standard blades 11 degrees of max pitch will be appropriate.
Of course you can set up the maximum the model will support but be careful of overloading and bogging the motor when doing hard
maneuvers with large collective/cyclic pitch inputs.
If you are using modified motors then the rotor blade size and pitch curve settings will vary depending on the configuration
Gear Ratios
The standard 6.88:1 gear ratio has been found to provide good all around performance with a wide variety of model configurations.
There are two optional ratios 7.3:1 and 7.8:1 which can easily be changed by replacing the pinion gear with optional ones. For more
information about whether these might apply to your circumstances contact Miniature Aircraft.
Running
In general terms, the model will operate just as any other internal combustion engine.
The model has demonstrated the best overall flight characteristics when operating between 1600 and 1950 RPM for the rotor head.
This can be adjusted for your particular style of flying and desired characteristics.
You will find that if you are using a new motor, it will take between 3 and 5 gallons of fuel for it to seat or “break-in”. You will notice
a change in exhaust tone and improved overall running as this occurs. You may also need to adjust the mixture settings on the
carburetor as the engine breaks in or if there are significant changes in operating conditions especially temperature, humidity or
altitude.
There are too many possible combinations to properly describe the approach but in general terms you can check the color of the spark
plug to determine the mixture setting.
• If the spark plug has milk chocolate brown color, the mixture is roughly correct
• If the spark plug is grey or white, the mixture is too lean
• If the spark plug is black and/or oily the mixture is too rich
Never lean either mixture needle to less than 1-¼ turn from fully closed unless there are specific directions included with your motor
that instruct otherwise. The carburetors typically found on these motors will be very lean at settings less than this.
If you find that the motor stops abruptly either during spool-up or while flying, if the model has plenty of fuel in the tank then the mixture
is likely too lean. If it stops on spool up, adjust the low speed needle, if it stops while flying adjust the high speed needle.
These are over simplifications of the tuning process for more information consult with Miniature Aircraft or with a local Team
representative or consult one of the gas specific forums mentioned at the end of this section.
Additional Support References:
Gas Powered Thoughts -
http://www.gaspoweredthoughts.com
Run Ryder Gas Forum or Miniature Aircraft Forum -
http://www.runryder.com
Helifreak Gas Forum or Miniature Aircraft Forum -
http://www.helifreak.com
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