The Wheel Horse on the left is a 1968 model with 3 forward and 1 reverse speed. Last year I replaced the engine for the second time with a Honda GC-160 which I really like. It is thrifty on gas and extremely easy to pull the rope to start. On the right is a 2 wheel Gravely from the 1980's. Originally it came with an 8 horse power Kohler which I replaced with a 9 hp Robin and after that wore out I just put in the Briggs of about 10 hp recently.