Circuit Transmission Ratio

Discussion in 'Circuit' started by Ndiddy1062, Sep 21, 2017.

  1. Ndiddy1062

    Ndiddy1062 Member

    6
    3
    Sep 16, 2017
    Hi, everyone,

    I usually have fantastic google-fu, but, alas, my search engine skills have failed me. I have searched high and low for the transmission ratio on the 2wd ECX circuit to no avail. Would anybody happen to have this info?
     
  2. Jeb

    Jeb Well-Known Member

    188
    56
    May 29, 2017
    The stock gearing is determined by the spur to pinion ratio which is 87/18 or 4.83/1 meaning the pinion has to turn 4.83 times to turn the spur one full turn. I've run mine at 87/23 which is wicked fast But also heats the motor up fast and impractical on our short course track. Which is 3.78/1.
     
  3. Ndiddy1062

    Ndiddy1062 Member

    6
    3
    Sep 16, 2017

    Thanks for the reply! Unfortunately, I am looking for the transmission ratio so I can calculate my overall gear ratio. Looks like I am not going to be able to take the lazy way out this time LOL. I will disassemble the transmission this weekend, count the teeth, and calculate the ratio. I will also post my results in case I can save someone else the trouble :).
     
    Jeb likes this.
  4. i_r_beej

    i_r_beej Well-Known Member Supporting Member

    660
    206
    Feb 9, 2016
    Unfortunately I don't have that information on hand. (Although I seem to recall jotting down the internal gear ration somewhere...) I believe that it's approximately 2.5:1

    Yes, please let us know what you calculate. (Although I'm going to be servicing the differential on my 2WD Circuit this week so you'll maybe beat me to the ratio calculation.)

    Here's an EXCELLENT resource on transmission gearing: https://www.teamassociated.com/pdf/cars_and_trucks/shared/gear_ratios.pdf
     
    Jeb likes this.
  5. i_r_beej

    i_r_beej Well-Known Member Supporting Member

    660
    206
    Feb 9, 2016
    Found this via Google. Cached post on UltimateRC forums (which are currently down):
    Screen Shot 2017-09-26 at 2.45.59 PM.png
    I presume that this is a 2WD Torment (which has the same transmission as all the other 1/10 2WD ECX cars).

    In case the graphic is not visible, the text reads:
    The transmission gear ratio is 2.64
    The stock spur is 87.
    Torment tires are about 4.25"
    Curcuit tires are about 4"
     
    Ndiddy1062 and Jeb like this.
  6. Ndiddy1062

    Ndiddy1062 Member

    6
    3
    Sep 16, 2017
    Thank you for the response, everybody on this forum is so friendly!
     
    i_r_beej likes this.
  7. i_r_beej

    i_r_beej Well-Known Member Supporting Member

    660
    206
    Feb 9, 2016
    You're welcome! And welcome to the forum!
     

Share This Page