If your Troy-Bilt J860 self-propelled mower is moving too slowly when mowing your lawn, the drive cable or variable speed cable on the unit can be adjusted. The adjustment will increase the throttle and speed up the mower's engine, in turn making the mower travel faster. You'll have to access the inside of the machine where the variable drive cable is connected to make the necessary adjustments.
Press the “Start” button or pull the “Recoil Starter” to start the machine. Move the shift lever into third speed.
Turn off the engine and remove the ignition key. Disconnect the spark plug wire from the spark plug.
Move the shift lever back to the first speed position.
Remove the three screws used to secure the harness assembly to the speed control housing with the screwdriver. Set the harness assembly off to the side.
Remove the three screws on the cover of the speed control housing and set the back cover aside.
Locate the eyelet of the variable speed cable. Detach the cable with the needle-nosed pliers and move it one slot to the left.
Replace the back cover and tighten the screws.
Place the harness assembly back on the speed control housing and tighten the screws. The tab on the harness needs to snap into the slot on the housing.
Reconnect the spark plug wire and start the engine to see if the mower's performance has improved.