From the 2001 FIRST Robotics competition Manual, Robot Appendix: H Part specifications...
Can be found at
http://www.usfirst.org/2001comp/Docs/
"The Robot - Part 4"
"Fisher-Price motor information
The following are approximate performance data for the Fisher-Price motor/gearbox sets supplied in the kits. The motor used is a Mabuchi model RS-550PF-6534.
Motor no-load speed 15,000 RPM
Motor stall current 57 A
Motor stall torque 0.363 N-m
Gearbox ratio 147:1
No-load speed w/gearbox 100 RPM (estimated)
Stall torque w/gearbox 34.7 N-m (estimated)"