Need Help With Weedeater Setup

[Jamie197235]

I'm building a friction drive setup with roller on top of wheel. My question is what is the easiest way to raise the roller off the wheel if I want to quickly disingage it?

 

[stude13]

it seems like most have clutch handle and cable to lift it.

 

[Esteban]

Mucho info, here;
http://www.motoredbikes.com/showthread.php?t=4770