Regarding motorcycle parts, today’s trend is to re-engineer classic designs with current technology to improve durability, reliability and performance. S&S Cycle did it with its new Shovelhead, Panhead, and Knucklehead engine designs and Bert Bakers follows by providing an essential piece of the combo, the tin primary. BAKER took that classic 1936-64 tin design and re-constructed it with billet 6061-T6 aluminum to facilitate alternator left side motor case and 1990-2006 starter compatibility. Tin primary leaks of the past are also gone… The resulting TTP (Tin Type Primary) looks, feels like the original one. Kick-only and starter configurations are available with shot blasted ‘raw’ or show polished finishes. The starter version is set up for factory 1.4kw 1990-2006 units. Stock tin derby and inspection covers will fit but the sleek TTP 6061-T6 aluminum covers are pure money. The chain tensioner design utilizes a fine tooth modern L-bracket, giving you plenty of room for any and all configurations.
The TTP can be ran wet or dry. The inner primary incorporates the chain oiler feed and return provisions on the back side similar to factory locations so you can continue to run Shovelhead era factory clutches; with all the fittings & hardware included. For a cleaner look with better clutch function, heat dissipation and dependability the TTP can be ran wet. By bypassing the conventional stock oil drip and suction lines, using the provided hardware, you can run the TTP just like a stock 1990-2006 primary. Compatibility is listed below. A new BAKER 4-Speed Catalog is available by calling 1-877-640-2004 or online at BAKER Drivetrain Catalog.
TTP Is Compatible With.
– 1970-E84 Big Twins and custom 4-speed builds
– 1970-79 ratchet top 4-speeds (top or bottom pull)
– 1980-E84 turtle top 4-speeds (kick only TTP version)
– Jockey top 4-Speeds
– BAKER 6-into-4
– Alternator style motor cases
– Stock 1970-E84 Shovelhead clutches and BAKER splined mainshaft clutches
– 1990-2006 1.4kw H-D starters with ¼-20 or 10-32 shaft
– Traditional tin derby and inspection covers or BAKER TTP billet covers
– 1955-64 splined non-compensator motor sprockets (compensator will not fit)
– Stock 40007-36B primary chains
Primary Drive Configuration Options.
– 24* tooth motor sprocket, 37 tooth clutch sprocket, and stock 82 pitch primary chain (PN 40007-36B), for a 1.54 primary ratio.
– 22 tooth motor sprocket, 35 tooth clutch sprocket, and 80 pitch primary chain (available through BAKER) for a 1.59 primary ratio.
– 23 tooth motor sprocket, 38 tooth clutch sprocket, and stock 82 pitch primary chain (PN 40007-36B) for a 1.65 ratio.
*Note: 24 tooth motor sprocket is the maximum size that fits within the TTP envelope.
Stock Shovel ratios: 1.54 / 1.60 / 1.68 depending on year and model.