[Shop-talk] Lever-operated caster/wheel?

[Jim Franklin]

My table saw has a base that would raise up onto a caster with a foot-operated
lever, like this:

http://www.tools-plus.com/delta-50-2000.html

I have a plywood box motorcycle stand that I'd like to put wheels on, but only
for moving around. Once the unit is in place I need to retract the wheels so
it's stationary. I'm not having any luck on Google with "lever-operated
caster" etc.

Has anyone seen these cam-operated wheels? Ideally they'd be 6" or greater
pneumatic, but once I have the lever mechanism I can adapt bigger wheels.

thanks,