You get 4 CIMs a year with your KOP
We did this year, but we have a 6-CIM drivetrain and a practice bot. We cut ALL of our CIMs but two, so we had 6 and had to order 6 more.
Just curious, why do you care if you use unmodified CIMs on your practice bot? It seems like you have a quite a few modified ones that you could use.
Cause the shafts are too short cause we cut them 
Shaft collars are an excellent addition.
Using the motor’s own power to rotate the shaft while cutting can be done safely, just ensure a few things before beginning:
- Properly secure the motor to a fixed surface
- Have some kind of guide (shaft collars) to ensure a straight cut
- Ensure the motor will be rotating in the cutting direction of your sawblade
I’ve used this method on small electric motors, and once on the output of a Jeep’s transfer case (sye install on a TJ). It can be done safely, but be careful.
This is what we did this year for our drive cims. Some of the other mentors on the team definitely had to take a second look when they saw what we we’re doing, but it worked great. As you said, just make sure you don’t take to much of a pass while turning it down and you should be fine.
Here’s how we cut ours down to fit in a Versa-Planetary reduction gear.
Placed washers on the shaft until they were flush with the cutoff point. Using electrical tape, secure the washers from moving.
Place a portion of the shaft to be cutoff in a vise and put wood blocks under the motor to support it.
Use a zip disk in a 4 1/2 inch hand held grinder and cut flush with the washers acting as a guide.
Use a wire wheel in a grinder to clean up any burrs.
Took longer to write this than it did to do it.
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We put the to-be-discarded end of the CIM shaft in a vise, have someone hold the motor can, and cut through it quickly with a hacksaw, then file the burrs off.
Yea, this is for a versaplanetary box. I never thought of spinning the motor up with a hacksaw… I have some collars floating around, I’ll have to put the motor in the vice tonight and give it a shot. Thanks for all the suggestions 
Horizontal band saw works well for this too. Just takes a while, especially when your blade is a little dull
It has been the case for the past five seasons. Two are from AndyMark and two are in the Vex motor box, so that’s why it doesn’t look like you get 4 on the checklist. But you do!
As for cutting the shaft, Dremel wheel, and also if you want to be extra careful a pair of pliers or something to hold the shaft so it doesn’t spin. Works fine.
Don’t cut the shaft for funsies, but you need to in order to use it in a VP for example.
Self destructing lathe 
2 motors were provided in the 2002 KOP, labeled as Chiaphua motors.
There were 2 in the 2003 and 2004 KOPs, labeled as CIM motors.
4 were provided in 2005.
2006 and 2007 had 2 2.5" CIM motors along with 2 3" CIM motors.
2008-2012 had two CIM motors.
2013 had 2 CIM motors along with a miniCIM and a BAG motor.
2014-2017 had 4 CIM motors, a miniCIM and a BAG.
Source: KOP lists from the FIRST site, retrieved via the wayback machine. Links to all KOP lists (except 1994) on the FIRST Wiki here. They are links to archived versions, so they won’t disappear until the wayback machine disappears.
I’ve been studying the lists for a couple months now. It’s quite interesting what you can learn. Like that Victor 884s have been legal since 2003, longer than any other motor controller to date.
If you’re just wanting to put them in a versaplanetary gearbox you don’t need to cut them. We just Used the CIM adapter and then use any other zillions of spacers and it will fit just fine.
“Zillions of spacers” in this case will reduce the quality and robustness of the CIM mounting to the VP. Flush mounting to the adapter, piloting using the CIM boss, etc. make for a much stronger and more efficient connection than a bunch of spacers. The most robust solution is to cut the output shaft to size.
I’m guilty of enjoying that method too.
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