80 year old friend of the family just picked up a 2008 year model rear tine Snapper tiller, with a 206cc Briggs Intek. Runs great, but whether the engine is half speed or full speed and you engage the transmission, it takes off like a rocket, much to fast for an 80 year old to handle and even for my 29 year old self. Moves so fast it pulled out of his hands and went sideways. Is there any way to slow it down or make and adjustment to put it at a walking pace?