My proublem is the tractor want hold its ground speed . I adjust the friction washer from time to time an it helps but its a fine line between to tight an to loose . I was wondering thats not suppose to be a special washer is it with some kind of friction material on it ? I know its not going to maintain its speed when the terrain changes say from level to a incline . But it just gradually slows down unless you constantly keep your hand on the lever . An it does something else when it crest a hill an starts down it will pickup quiet a bit of speed before it catches its self an starts to hold back . I usually just pull the lever back an catch it before it takes off, but is this normal ?