My old Toro Super Recycler got so it's self propulsion would cause resistance when I tried to back it up. It was a simple belt to gear box system where the the rear gear axle would pivot to loosen or tighten pressure on the belt. But even loose that belt would still want to turn the pulley creating some resistance to rolling it backwards. I'd try and adjust it looser but then the mower would loose pull. What I'm wondering is do other mowers or self propelled systems solve this problem? I don't want front wheel drive it just makes the mower heavier to tilt and stuff. But most rwd (rear wheel drive) mowers are driven by belts turning gear boxes it seems, and I don't want another Toro Recycler experience with the mower not free rolling in reverse. Some people praise those blade brake clutches that let the blade disengage from the running engine, but is there any similar thing for drive systems, a clutch that can freely disengage the drive for free roll reverse? (Heck I always thought it would be nice to have finger controllable reverse on a 21 or 22 inch mower like the hydro walk behinds have). Any way are there mowers that can pull backwards with out resistance from the drive system?