Speed 900-gear ratio

[psycho_fling]

hi all

for my crusher i now want to use 2x speed 900s, running on either a 25a abertooth or a scorpion xl/xxl-all running off 21v

however i would like to know a suitable gear ratio to use, in order to get good speed and high pushing power

any info/ help welcome

thanks alex

[maddox]

Depends on wheel size.

Let us take a 80mm Colson as the wheel.

@21V the Speed 900 runs 11550 rpm.
Aimed for speed is 20km/h

gives me a 9 or 10 to 1 gear ratio.
Youll end up with a 2 stage gearbox.

With a 8-1 gear ratio youll get about 24km/h

[psycho_fling]

i was looking at using either 100mm wheels or 75mm ones

[maddox]

Simple calculation then.
1-10 ratio on a 100mm wheel gives 21 km/h
1-8 ratio on a 75 mm wheel gives 16 km/h

[psycho_fling]

so i can use the 100mm wheels? matt said they would be to big

by the 1-10 ration i would need the gear on the motor shaft to have 10times less notches on correct?
such as 5 and 50?

thanks alex

[maddox]

Aboutish.
But I doubt you can find a 5 teeth gear to fit on a 6mm axle.

[beast]

just go for the smallest T gear u can find and then the biggest size which is nearest the size off wheel if u want a 1 stage reduction

then guess the ratio and speed

[psycho_fling]

is this the right sort of layout?

the page should work (i hope)

http://psychoflingteam.piczo.com/robotimprovements?preview=y&cr=5http://psychoflingteam.piczo.com/rob...preview=y&cr=5

also where do i buy the gears from?

thanks alex

[leorcc]

Your Example is a single stage reduction, with 21V that will be really fast. We use a single stage with speed 900s, but on 12V and even then if we dont put our armour on it pulls a wheelie every time.

http://www.computerclub.nl/uploads/msrconcept.jpghttp://www.computerclub.nl/uploads/msrconcept.jpg

You can find gears in several locations, one of them is RS Components.

http://uk.rs-online.com/web/http://uk.rs-online.com/web/

[maddox]

We have driven the Hannibalitos with dual rate, so the voltage supplied to the motors was less than 6V, and still they are fast and fast accelerating.