I have a 11hp craftsman mower 80's model. Engine is in front.the problem is it jerks you back hard ideling low to mid rpm rande in 1st and pulls the wheels off the ground in 2nd gear.belt driving clutch from what I can tell and the pully’s all seem to spin freely.uses one pedal for clutch and brake and no matter how easy you let out on it it will pull the wheels off the ground.brake works greak with easy stoping.please help if you can thanks a million God bless

Hi,
That was a fairly common complaint in those days. It does it because the belt grips so well at the front and rear. The only possible solution is to find a Murray transaxle pulley to substitute, since it grips on the inside of the belt instead of the two "V" sides. That will give a small amount of slip to the system. Problem is it will have to be fairly exact since no linkage adjustment is present.
Peace,
Clarke