Pro

Just got off 300 rc was doing some mowing today in tall grass when the ipto started to slow down when the motor was running wide open. What"s the deal do the bands need adjusting?? Has never happened before. Thanks

That would be the first thing to try.

My method: Assure that there is no (an I mean near zero) play in the linkage or slippage at the lever pivot. If there is fix that first or no other adjustment will be valid.
next: (engine off)
Place the lever in the measured center of its travel between locked in the off position, and locked in the on position. (might need to be wired to the location)
Remove the band adjustment cover (peanut dome).
With nothing on the shaft, try to turn it with your hand. (it should turn with not much resistance)
Tighten the front adjusting screw while feeling the shaft resistance to turning. tighten until it is not possible to turn it by hand, (no tool or bar)
tighten it 1/4 turn more.
then loosen it till you can just begin to turn the shaft by hand, then loosen 1/2 turn. (it should be free to turn now)
Now tighten the rear adjustment screw till it is not possible to turn by hand (as above)
Tighten 1/4 turn more.
back it off till you can just turn it, and loosen 1/2 turn more. (again it should be free to turn)
The adjustment screws should be sticking out of the jamb nuts. If they have gone deep, and there is little or no lock nut threads left, the bands are worn and should be replaced or relined (better option in the pocket book).
if adjustment is not working or the threads run out it may not be possible to adjust it to work.
If OK, it should be functional now. Take off the hold wire and try it. Jim