[Als48]

I once had a lawn tractor (Simplicity) that had a push/pull throttle. It had a speed control built into the dashboard mount for the cable mechanism. You could pull the throttle out to your desired engine speed, then lock it in place by rotating the knob clockwise. When you desired to reduce the RPM's you would turn it counter-clockwise to its free position. You could then, push in or pull out as desired. This works similar to a drill chuck or collet, that applies a locking force on the sliding shaft, which is a little larger (about 1/4" OD) than the cable itself. That principle could be applied here to the hand throttle if one could find a mechanism like i described.

Al Hook