Milwaukee Twins Starter Jackshaft Pinion Gear For Harley Big Twin The Milwaukee Twins Starter Jackshaft Pinion Gear offers a seamless fit as a replacement, adhering to OEM specifications with its 10-tooth design for dependable engagement. Its engineered for durability and precision to ensure smooth operation of your starter. Formerly offered under the J&P Cycles brand. Features: For replacement of stock parts or anything aftermarket designed around OEM model 10 tooth pinion gear Replaces OEM 31342-94