Revco gears change pinion T...

[bpd964]

Quick question...

I upgraded to the revco gears.. (1st gear 68T / Main gear 61T) and now Instead of having to decide on 11t/13t/14t etc. I now have to decide on 21T,22T.. I have the Z20/980 motor and want to be in the 2000-HS range... which pinion should I use or better yet, how can I calculate that type of stuff?

Thank you all in advance...

[Madedon]

I m using the 19 Pinion 61Main 21OWB 68 Secondary giving 2027 HS (Include 6% drag).

Please find bellow the calculation


Motor First Pickup Second Headspeed RPM
Battery Motor Max Pinion Spur Gear Gear Spur Gear Ratio Drag Drag Hover Max
Voltage KV RPM Teeth Teeth Teeth Teeth 0% 6.5% 11.7% 20.0%
23 980 22540 19 61 19 68 11.4903 1962 1834 1732 1569
23 980 22540 21 61 19 68 10.3960 2168 2027 1914 1735
23 980 22540 23 61 19 68 9.4920 2375 2220 2097 1900

23 980 22540 19 61 21 68 10.3960 2168 2027 1914 1735

MAX RPM = KV * VOLTAGE
GR #1 = FSG / MP
GR #2 = SSG / PG
RPM = Max RPM / (GR #1 * GR #2)
Gear_Ratio = Main_Gear * Secondary_Gear / Autorotation_gear/ Pinion

[bpd964]

I m using the 19 Pinion 61Main 21OWB 68 Secondary giving 2027 HS (Include 6% drag).

Please find bellow the calculation


Motor First Pickup Second Headspeed RPM
Battery Motor Max Pinion Spur Gear Gear Spur Gear Ratio Drag Drag Hover Max
Voltage KV RPM Teeth Teeth Teeth Teeth 0% 6.5% 11.7% 20.0%
23 980 22540 19 61 19 68 11.4903 1962 1834 1732 1569
23 980 22540 21 61 19 68 10.3960 2168 2027 1914 1735
23 980 22540 23 61 19 68 9.4920 2375 2220 2097 1900

23 980 22540 19 61 21 68 10.3960 2168 2027 1914 1735

MAX RPM = KV * VOLTAGE
GR #1 = FSG / MP
GR #2 = SSG / PG
RPM = Max RPM / (GR #1 * GR #2)
Gear_Ratio = Main_Gear * Secondary_Gear / Autorotation_gear/ Pinion


HUH?:dontknow

[Vinger]

I m using the 19 Pinion 61Main 21OWB 68 Secondary giving 2027 HS (Include 6% drag).

Please find bellow the calculation


Motor First Pickup Second Headspeed RPM
Battery Motor Max Pinion Spur Gear Gear Spur Gear Ratio Drag Drag Hover Max
Voltage KV RPM Teeth Teeth Teeth Teeth 0% 6.5% 11.7% 20.0%
23 980 22540 19 61 19 68 11.4903 1962 1834 1732 1569
23 980 22540 21 61 19 68 10.3960 2168 2027 1914 1735
23 980 22540 23 61 19 68 9.4920 2375 2220 2097 1900

23 980 22540 19 61 21 68 10.3960 2168 2027 1914 1735

MAX RPM = KV * VOLTAGE
GR #1 = FSG / MP
GR #2 = SSG / PG
RPM = Max RPM / (GR #1 * GR #2)
Gear_Ratio = Main_Gear * Secondary_Gear / Autorotation_gear/ Pinion
Dubble HuH, and a 21 teeth OWB, where and how?

[Happy|Harry]

i've attached an easy to use headspeed calculator in this post here >> http://www.helifreak.com/showpost.php?p=579474&postcount=10 :)

[Stallion]

Hi guys!

i use the 68T Revco gear as well. at the moment it gives me 2400RPM with a 23T Pinion.

@Happy Harry: Nice Excel sheet but not suitable for the Revco gears with diverent Pinion sizes. Could you make the Pinions adjustable as well?

On www.ReadyHeli.com is a Headspeed calc for the hurricane! Thats what i was useing for my calculations.

http://www.readyheli.com/Online_Headspeed_Calculator_s/81.htm

Good luck wiht you numbers!!!

Good light Good night

[Happy|Harry]

i don't see the need to use the smaller 0.6mod revco gears, (who changed it to 0.6mod because the company who makes his pinions don't make 0.8mod pinions ;)) so i didn't plan for them in the spreadsheet, sorry :) if you use them because the gears are white instead of black you could use the microheli replacement gears instead and these use the same ratios as the gaui gears