Do some speedo's only work with some motors or receivers

Hi
I am trying to make a crusher antweight with precsion micro drive motors and for the claw motor
I have bought a mini v2 speed controller. Will this set up work because before progress I would
like to know. By the way my receiver is a planet micro 2.4ghz advanced one.
Be grateful for any help.

I presume you mean the Scorpion Mini V2, which is a single motor controller. Yes it will work, but every motor would need its own controller then. 2 Precision motors would need 2 Scorpion minis, and 1 motor for the claw would require a third controller. The Scorpion Mini V2's are nice controllers, but running three of them in a single bot is becoming a bit much in terms of size. You could also take a look at the Speed controllers Peter Waller makes for Antweights:

http://antweightwars.co.uk/Controllers.htm

The only imcompatibility I've found is that the Corona micro 40mhz recievers don't work with Peter's controllers because of the odd way they relay signals. Everything else should talk to each other fine though.

Thanks for the help with that one
In the mini v2's case they provided a diagram of how to wire it up however it shows to connect the battery to the speedo. Can it run from the RC cable on its own.

Nope, you need to have a battery connected to the speed controller otherwise it's got no power to deliver to the motor.

Thanks for everyones help I am a bit closer to completion

Just a quick point: If you are using 3 scorpion mini's, cut the red RC wire on 2 of the controllers, because the scorpion Mini's produce a BEC (battery eliminator circuit) to power the receiver, and you don't want 3 of them going into the RX. the 3 scorpions will have to be wired in parralell to get the same power to all 3 controllers.