R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Electric On-Road (https://www.rctech.net/forum/electric-road-2/)
-   -   chose spur gear? (https://www.rctech.net/forum/electric-road/116921-chose-spur-gear.html)

gtimax 06-07-2006 06:39 AM

chose spur gear?
 
I play ta05 , the original spur gear is 64p 105t, can I use 100t?(with same final gear ratio 8.0 for 12turn)
I felt 100t is faster then 105t (8.0 final) .
what spur gear is the best? if I use smaller spur gear , what side effect will occure(heat raise)? will it hurt the esc? can i notice it?
what is the limit/concern of choosing spur gear?
thanks!

Darkseid 06-07-2006 08:14 AM

Well I'll take a shot at answering this...

IF your currently using a 108t spur and your final is around 8.0, then your likely using a 30t pinion. (108/30=3.6*2.25=8.1 final)

So if you drop down to a 100t spur and keep the same pinion, you'll end up with a final of 7.5(100/30=3.333...*2.25=7.5 final)

The result of this is that you will have more heat in your motor and speed control, and the ratio is probably a bit too low for a 12turn mod.

Now if your trying to go to a 100t spur while still keeping the final around 8.0, then you'll have to go down on your pinion size to something like a 28t pinion. That will give you a final right around 8.04.(100/28=3.57*2.25=8.04)

The only concerns that you really have with picking a spur gear is:
1. does it fit (most spur gears fit the Tamiya mount)
2. what ratio do you want
3. can the spur and pinion fit with the size gears you've choosen. In other words, will a small spur reach a small pinion and/or will a large spur still fit with the large pinion you want to use.

I hope the answer you were looking for was somewhere in all of that. :lol: :cool:

gtimax 06-07-2006 08:19 AM

thanks for the reply
are you meaning that it is no different if the final ratio not change?
I heard that the loading will be higher if the spur gear is smaller and the top speed will higher when the final ratio is not changed. the problem is I don't know the limit is?

Darkseid 06-07-2006 08:24 AM

That is what I'm saying.

If your final ratio is still 8.0, then whether your using 108/30 -or- 100/28 it will still feel the same and be the same temp wise.

That is what I've always known, but if there is someone with contradictory information, maybe they'll share it. (I'm always looking to learn something new :D )

But as far as I know, the final ratio is the final ratio...no matter what the gear combination is.

On my TA05 I went from using a 100t spur to using a 98t spur(broke a spur gear tooth that day and shop didn't have another 100t) and I just change the pinion to keep me at around the same final ratio. I never noticed any difference in the motor or speedo temp, or in the car performance.

gtimax 06-08-2006 03:56 AM

anyone have an idea?

KoE 06-08-2006 05:23 AM

i'm going along with darkseid on the spur/pinion combo & fdr thingy but i believe you are looking for discussion on this ==> Gearing Technique - Better Acceleration (http://www.rctech.net/forum/showthread.php?p=450829 )


All times are GMT -7. It is currently 07:46 AM.

Powered By: vBulletin v3.9.3.8
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.