Transmission Base Plates

Reproduction of the stock 4-speed transmission mounting plate as used from 1936–64. Can be used on later 4-speed models thru 1985, too.

Faithful reproduction of the stock 4-speed transmission mounting plate with 3 front holes as used by the factory from 1958–61. Precisely machined from quality Domex 350 steel with all the accurate details to make it a perfect stock replacement. Correct for the indicated year group, however, they fit all 4-speed Big Twins 1936-1985

Bullet-proof version of the stock 1965-1985 transmission mounting plate which is guaranteed not to bend or flex. Precisely cut from high quality S 355 construction steel, with 2 square front holes to work with carriage bolts (stock equipment 1977→). Unlike original plates it is machined out of one solid piece of steel to provide extra rigidness. The two-window design makes it compatible with pre-1965 transmssions, too. However, you will require a custom primary chain tensioner in these applications. Recommended when using a Cannonball SSK-S electric start system or a high performance engine.

Precision-machined transmission mounting plate with built-in dual adjusters. Ideal for use with open belt drives. Features three front mounting holes to match early and late frames.