I was in the confidence during Daytona Bike week. One of the bikes riding around the city and on the I95 was test-equipped with a prototype 7-speed transmission. The Baker DD7 is being developed as a direct replacement of the Cruise Drive Harley-Davidson factory 6-speed to improve it in many ways. 1- Factory 1st gear ratio is too tall (numerically too small). The DD7 has a shorter (numerically larger) 1st gear for easier launches. 2- Shift clunk. In transmission design, be it automotive or motorcycle, low mainshaft weight is always desirable for smooth and quiet shifts. Audible shift clunk in the factory 6-speed is caused by the heavy weight and resultant high inertia of the 1-piece forged mainshaft. That mainshaft is a one-piece design that includes1st, 2nd, 3rd, and 4th gears. The DD7 mainshaft is light weight and only includes the small 1st gear as an integral part. 3- Shift smoothness. Shift smoothness in the factory 6-speed is a definite improvement over the 5-speed. The DD7 is a big improvement over the factory 6-speed because it incorporates a new linear roller ball detent as part of the supplied Billet Top Cover. This linear roller ball detent is similar to the type first used in Baker TorqueBox transmissions. 4- Gear noise. The factory 6-speed has straight cut 1st and 5th gears. This yields gear noise in 1st and 5th.The Baker DD7 has a full set of helical gears for quiet operation in every gear.
The Harley-Davidson factory 6-speed ratios are: 1st (3.34), 2nd (2.30), 3rd (1.71), 4th (1.41), 5th (1.18), 6th (1.00). The Baker DD7 transmission will have the following ratios : 1st (3.76), 2nd (2.75), 3rd (2.06), 4th (1.55), 5th (1.27), 6th (1.10), 7th (1.00).
In this new Baker DD7, Shift Drum is designed to help the rider find Neutral every time, like with all other Baker Transmissions. Testers tell me that the bike felt like motor work has been done to it and that it shifts like a dream. Baker Drivetrain.