No Toy Robotics

[Mouldy]

I'd go 9:1 with MOD 1

[maddox10]

Biggest gearratio you can get in 1 stage on a speed 900 is Z10 mod 1 on the motor and the wheelsize gives you the maximum size of gear.
A Z50 is 52mm external diameter. Giving you a minimum wheel diameter of 55mm.
Chaging to a Z100 and a 110mm wheel won't change speed.
But to give you an idea. Kashei uses 6S and a 6-1 gearratio to a 90mm wheel. It's bloody fast, and uses amps like no tomorrow. We needed to put in a Sidewinder, no other small controler like the Scorpion XXl Ilyama version or the IBC could do anything with it. ( 31km/h is idioticaly fast)
The TZ85's will handle it, but those , in our opinion, lack the fine control the dedicated twin motor controlers give.

[MikeNCR]

Biggest gearratio you can get in 1 stage on a speed 900 is Z10 mod 1 on the motor and the wheelsize gives you the maximum size of gear.
A Z50 is 52mm external diameter. Giving you a minimum wheel diameter of 55mm.
Chaging to a Z100 and a 110mm wheel won't change speed.
But to give you an idea. Kashei uses 6S and a 6-1 gearratio to a 90mm wheel. It's bloody fast, and uses amps like no tomorrow. We needed to put in a Sidewinder, no other small controler like the Scorpion XXl Ilyama version or the IBC could do anything with it. ( 31km/h is idioticaly fast)
The TZ85's will handle it, but those , in our opinion, lack the fine control the dedicated twin motor controlers give.

Might be worth giving these a look- http://e0designs.com/products/ragebridge/

I'm using one to drive a feather with two 18v Dewalts on a 6s Lipo. I've been very happy with the performance and control. The adjustable current limiting is a really handy feature.

[maddox10]

The Ragebridge looks ok, but we have the Sidewinder in our supply, so for weight or dimensions we don't have to change.
Also, we don't need all that power in Kashei, but the 6S battery is mandated by the axe. Otherwise we could be happy with a 3S 2200mAh.

[adz600]

thanks for replys here is a link to the motors already have 2, botbitz85 are ready to be hacked. can only use the 900s on single reduction due to weight and size issues could use a voltage step down if required.

[adz600]

http://www.ebay.co.uk/itm/2009126068...84.m1423.l2649

[Ellis]

Theoretical top speed of almost 18mph. Much more reasonable. Don't know much about that model of 900, chances are they're all torque (especially at double nominal voltage), as they're very low revving, in which case you should be fine.

[razerdave]

They look to be the legit versions: longer can, seem to have the internally mounted capacitors.

[adz600]

http://www.technobotsonline.com/gear...del-gears.html
these gears look good value and very light, anyone used them

[Ellis]

Generally seems the tooth width is just 4mm. That's very small for a feather drive. I'd expect those mega motors to devour them.

(never seen them on there before though, nice for beetle scale!)