Main Pulley 37T - Goblin 630/700/770

The new 37T main pulley which is the replacement for the old 36T pulley (H0016-S) is designed to increase the tail ratio a bit (New tail gear ratio is 4.67:1 compares to 4.53:1 of the old pulley) to improve tail performance and authority. In addition the new pulley comes with new screws.