House Bill 72S1 (passed in 2008) repeals all class M licenses as of July 1, 2008.
Also, new restrictions for Motorcycle endorsement permit holders. For more information click here.

Effective July 8, 2008, a new rule will be in place which will require all new motorcycle riders to be restricted to riding a motorcycle based on the cc size of the motorcycle upon which the rider is tested. The following 3 restrictions will be used:

O = 90 cc or less Motorcycle
2 = 249 cc or less Motorcycle
3 = 649 cc or less Motorcycle

If you are tested on a motorcycle 650 cc or greater no restriction will be placed on your license and you will be permitted to ride any size motorcycle.

http://publicsafety.utah.gov/dld/documents/MotorcycleCombinedSheet7-08_001.pdf