[DonRotolo]

I would speculate that they do have the room to mount the encoders he linked to. It's mounted to X bar and should be able to slide back an inch or more.

Jengles, those encoders would be a good option. Although less costly options exist, those may require more work to get them installed.

Another consideration: at 128 pulses per revolution, times about 1000 RPM, 128,000 pulses per minute is a lot of data. In software, there is a way to count only every "Nth" pulse (like every 8th pulse for example) that will allow your software to not have to spend all its time counting pulses. Have your programmers look into how that's done, as they'll need to learn how eventually....