Pinion gear teeth/ motor turn chart..

[DusterX17]

Hey there,

i was wondering is there some sort of standard chart for the number of theeth a pinion gear, (and spur gear) should have for various turn motors?

brushed and brushless (cus brushless can handle 2 teeth more because of high torque right?)

i know its 24 theet for a stock motor, and 23 for a 14 t motor, so what would you use inbetween? (like 21t.. 19t?)

correct me if i'm wrong thanks :]

-Duster

[DusterX17]

Can someone at least tell me what teeth pinion gears can be used for a Novak ss5800 brush less motor?

I've heard that its equivalent to a 10t motor, meaning it should take a 18 tooth pinion but then I've also heard that brush less motors have enough torque to handle up to two teeth more, i really don't want to break anything with a dumb mistake like this, so can someone please tell me what sort of pinion gear to use with my b4?

(not sure of the proper name) but the other big gear that the pinion gear attaches too (the spur gear?) how many tooth should that be? there 2 types right? 81 and 74 tooth? or something of the sort..

thanks..

-Duster

[Jonny_H]

You need to either:

a) tell us what car you have (the 'internal ratio', between the layshaft and wheels, is different for different cars); or

b) talk about overall ratio (motor revolutions : wheel revolutions) rather than just pinion teeth.

HTH!

[josh_smaxx]

There isnt really a standard chart, you just need to find out the best ratio for your motor, according to your other thread you run a B4, so thats a 2.6:1 internal ratio, with a kit 81t spur gear, 18t pinion and standard buggy tires at 81mm dia. that would give you and overall ratio of 11.70/rollout of 21.75mm (how far car travels to one revolution of the motor) find out on the novak site or something what the ideal ratio for that motor is and work from there, its fairly easy once you get your head around the basics .

[super__dan]

An SS5800 isn't quite up to that of a 10t. Assuming you have the kit 81t on your B4 I'd start with a 20tooth pinion and go from there. Run it a few minutes and see how hot it is, temperature is a very good indicator of gearing.

[DusterX17]

Awsome thanks,

okay so let me check my math here..

the manual for the Novax motor+ esc says that a ratio of 6.5:1 is the max anything lower and it is very dangerous (i think i'll stay away from 6.5...) and they recommend a 7.3:1 ratio overall.

so i did this.. (spur/pinion)*2.6 = 7.3 and if i solve for pinion gear i get
pinion = spur /(7.3/2.6) = 81/(7.3/2.6) = 28.8 (28-29t)

and for 6.5:1 ratio i get 32.4 (32t)

so does that mean anything below 30t is safe to use?

and anything below about 20t would result in the motor spinning alot but not moving that car as much?.

(i'm also guessing anything near the high 20s would result in something hard to control fast)

does my reasoning sound fair enough?
thanks

-Duster

[josh_smaxx]

Well to get that ratio it requires a 29t pinion, im thinking that will make it run really hot, it sounds way over geared to me, i thought you would be wanting to look more at a 10:1 ratio

[RogerM]

That sounds very tall gearing to me .... where did you get your target ratio from?

Novak's instructions ....

http://www.teamnovak.com/download/in...pecgearing.pdf

..... suggest about 9:1 ..... now if they are as conservative as they seem to have been on the 5.5R I use it is likely to stand a couple of teeth higher but probably no more than say 8:1

[josh_smaxx]

To get 8.42:1 its a 25t pinion, that seems massive to me

[gazbaz2]

Originally Posted by josh_smaxx

There isnt really a standard chart, you just need to find out the best ratio for your motor, according to your other thread you run a B4, so thats a 2.6:1 internal ratio, with a kit 81t spur gear, 18t pinion and standard buggy tires at 81mm dia. that would give you and overall ratio of 11.70/rollout of 21.75mm (how far car travels to one revolution of the motor) find out on the novak site or something what the ideal ratio for that motor is and work from there, its fairly easy once you get your head around the basics .

or a more simple way......have a look at the novak instructions, there you will find a starting point and forget about the bloody wheel diamitor, there all the same or there abouts, Josh is just trying to confruse you matey, dont need to know all that, just need internal ratio.

[gazbaz2]

just put the smallest pinion you can get on the 81 spur or put an 87 spur on, thats what i did, and the car was ballistic plus ran very cool

[josh_smaxx]

Originally Posted by gazbaz2

or a more simple way......have a look at the novak instructions, there you will find a starting point and forget about the bloody wheel diamitor, there all the same or there abouts, Josh is just trying to confruse you matey, dont need to know all that, just need internal ratio.

I wasnt trying to confuse him, i did the hard work, well, i just used a simple gear calculator that required things like the tire Dia. to work out the overall ratio.

[gazbaz2]

Originally Posted by josh_smaxx

I wasnt trying to confuse him, i did the hard work, well, i just used a simple gear calculator that required things like the tire Dia. to work out the overall ratio.

No need to do all that HARD work though

[josh_smaxx]

Originally Posted by gazbaz2

No need to do all that HARD work though

I put 4 figures into a spreadsheet, internal ratio, tire Dia., spur teeth and pinion teeth. tells me everything.

[gazbaz2]

Originally Posted by josh_smaxx

I put 4 figures into a spreadsheet, internal ratio, tire Dia., spur teeth and pinion teeth. tells me everything.

I know, theres 1 at the club