I am a bit confused on if we are allowed to use last years CIM motors. It’s a noob question I know. Also there are 2 different kinds of CIM motors (2 of each) in the KOP this year right? 
Yes and yes. Read the Robot section of the manual.
can we use 2 of the older one and 2 of the 06’ ones? No belt drives. What’s the regulation?
I read <R25>, but I still don’t understand 
You can use the two new large CIMS you got this year. You can use the two smaller CIMS you got this year. And you can use two additional smaller CIMS from previous years, as long as they are identical to the ones you got this year. Total of 6 big heavy motors, if that’s what you need.
I know there are 2 different cim output bars. One of them are the bars with teeth, and on that is a solid bar. either one goes right?
The shaft type on the old cim motors doesn’t need to be the same as that on the new small cim as the motor itself has the same model number on it. i know in my team’s case one set had a key slot with the ends rounded off while the other had a continuous slot and they were both the same type of motor. as for what you mean about bars with teeth i have no idea what you’re talking about id follow Billfred’s advice and at least take a look at the pictures for the KOP that is in the robot section this year.
I took a look at the KOP list and they are 2 keyed ones. I think there were 2 keyed ones last year right??
2002 motors were not a round keyed shaft. They were a very stange splined shaft. You cannot legally use them this year. 2003 and up CIM motors have a keyed shaft. The length and exact shape of the keyway has changed slightly over the years, but you may use 2003 and up CIM motors. You may have up to 4 small CIMs and 2 large CIMs (minibike motor) on the 2006 robot.
Awesome, thanks so much 