Dr. Pulley 16x13 Sliding Roller Weights ADAracing Left Crankcase for 50cc 2-stroke

Left Crankcase for 50cc 2-stroke 1DE41QMB engines

choose a stronger clutch spring to increase the starting RPM

Tire size 120/70-12

Includes 6900Z bearings

Intake Manifold by ADA Racing for WYK carbs

Dr. Pulley 16x13 Sliding Roller Weights ADAracing Left Crankcase for 50cc 2-strokeDr. Pulley 16x13 Sliding Roller Weights for 50cc 4 stroke QMB139 engines. Please select weight from drop down menu. Traditionally, gear ratio is changed by the up and down rolling movement of the roller weights in the ramp of the Moveable Drive Pulley (MDF). Now the innovative Dr. Pulley Sliding Roller Weights slide up and down the ramp to change the gear ratio. This unique sliding movement (not rolling) provides exclusive advantages to increase CVT