Hydraulic homemade tractor walkaround

A couple of things I neglected to mention in the video;
-I used geroler motors. I had tried external-gear, gerolers have much better starting characteristics
-The spool valve incorporates flow control and a relief valve
-Starting torque is pretty good, no problem spinning the tires, even at low engine rpm.
-I installed disk brakes in the rear, the lever on the left is a drift car brake control accessory. Once I switched to geroler motors, the hydraulic braking improved dramatically, so I don't use the brakes much.
-One design goal was to be able to stand up while operating the tractor. This was achieved exclusively using hand controls, which works OK.
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