-Stock Class. Mowers must have stock frame, wheelbase, ride height, engine and transmission. No internal modifications of engines allowed. Differentials can be welded. Sheave changes allowed. Stock mower tires are required. Engines must be agriculturalstyle single or twin cylinder Briggs/Kohler/etc- type originally equipped on lawn tractors. Removal or bypassing of governors is acceptable. Welding front axle oscillation is allowed and recommended. Mower deck may be removed or left on ,if left on all cutting blades must be removed