hi dave

1: the drum should weigh about 2-3 kg depending on how many teeth i go for and the width of the robot, i need to get it all measured up befor i can say for sure but thats the rough estimate

2: 4000rpm? im not exatly sure what the average speed is for a drum

3: i was origionaly going for a 36vsystem but after talking to leo iv decided to go for 24v

4: hmm, well i guess its best to spend a bit more and get better results but id like not to get to ott...around £150-200 methinks but it depends on whats out there.

jack