teamitk
04-26-2007, 01:17 PM
I made up this ratio calculator to make it easy to figure ratios on my Hawk Pro; it is just a simple Excel file. Just fill out the areas in green, and it will calculate the overall gear ratio. On the bottom, you can input desired engine RPM and it will tell you the headspeed at that engine RPM with the tooth count entered, you can also input the desired headspeed and it will tell you the engine RPM for the tooth count.
Hope someone finds it useful. I have included the data on tooth count for the Hawk Pro as it ships, plus the available options on the counter gear and drive gear. If there is any interest, I would like to add the tooth count and available options for all 4-gear drive Century heli's. Feel free to post any other known tooth counts and what they fit, and I will integrate them into the calculator.
Notes: Primary ratio is how many times the engine rotates for one rotation of the countershaft; secondary ratio is how many times the countershaft rotates for one rotation of the mainshaft. Final ratio is how many times the engine rotates for one rotation of the mainshaft.
To do: go home and count the tail drive teeth so that the calculator will display tail RPM. That will be updated within a few days.
P.S. Thanks to Chris DeSain for giving me the available optional gear tooth counts and for pointing out the Hawk ratios to me in the first place.
Hope someone finds it useful. I have included the data on tooth count for the Hawk Pro as it ships, plus the available options on the counter gear and drive gear. If there is any interest, I would like to add the tooth count and available options for all 4-gear drive Century heli's. Feel free to post any other known tooth counts and what they fit, and I will integrate them into the calculator.
Notes: Primary ratio is how many times the engine rotates for one rotation of the countershaft; secondary ratio is how many times the countershaft rotates for one rotation of the mainshaft. Final ratio is how many times the engine rotates for one rotation of the mainshaft.
To do: go home and count the tail drive teeth so that the calculator will display tail RPM. That will be updated within a few days.
P.S. Thanks to Chris DeSain for giving me the available optional gear tooth counts and for pointing out the Hawk ratios to me in the first place.