Zodiac A to 6-speed conversion kits for Softail and Dyna with 5-speed gearbox - 1st and 2nd fork

The biggest drawback of 5-speed gearboxes is possibly the 1:1 ratio in 5th gear, which results in high revs if you ride at high speeds. You can change this by changing the final drive ratio, but this also affects acceleration. With the new Zodiac 6-speed gearbox you will have a 1:1 ratio in 5th, but in 6th you will have a ratio of 1:0.86, reducing engine revs by 14%. There are already other 6-speed gearboxes on the market, but none of them have the same quality as the Zodiac 6-speed, nor are they as affordable, nor do they have the manufacturing quality and CAD/CAM design of Zodiac gearboxes. The parts are CNC manufactured in the most modern transmission factory in the world. 

The Zodiac 6-speed gearbox is compatible with Dyna 5-speed models from 1991-1998 and Softail models from 1986-2006, provided a clutch from 1990 onwards is used. Available as a conversion kit, a builder kit, and a complete gearbox. The conversion kit includes the main shaft, secondary shaft, sixth gear pinion combination, complete selector drum mechanism, a pair of selector supports, shift fork, auxiliary selector fork with shift shaft and shift shaft support, shift locking system, clutch rod, billet aluminium gearbox cover with bearing plate, main shaft, 1st, 2nd, 3rd and 4th gears, speedometer plug with O-ring, and all necessary mounting hardware and easy-to-follow instructions for installing the Overdrive Conversion Kit on a Softail gearbox, using some parts from the used gearbox. If you do not wish to use any parts from your old gearbox, or if the gearbox is pre-1990, you can order our "Builder Kit", also available with a 25, 45 or 55mm longer shaft. These kits include all primary spacing parts, such as spacers, crankshaft extension, and crankshaft extension nut. They do not include the sump, seals, bearings, final cover with clutch mechanism, or top cover, nor any external parts. For those starting from scratch, we also offer complete 6-speed gearboxes. These gearboxes are suitable for models with electronic speedometers, and include a plug for the sensor hole if you wish to use a conventional cable-driven speedometer, whether from the front or rear wheel.

Where the difference lies:
• The first to fifth sprockets have the same width as original
• The sprockets and axles are made from highly fatigue-resistant 20CrMnT steel.
• Once machined, the pinions and shafts are tempered and relieved of machining fatigue, to an internal hardness of 35 to 45 and a surface hardness of 58 to 60 on the Rockwell scale.
• The sixth pinion and secondary shaft are a single piece
• Inner cover, machined from solid billet aluminium, allows for extra sprocket installation. 
• The selector drum is machined to high precision and features a bespoke needle bearing.
• The gear selection mechanism has been redesigned for precise and smooth shifting
• Now also available with main shaft 25, 45 or 55mm longer
• 5 years or 100,000 KM warranty on materials

The seals, oil seals, and O-rings are the same as for the original 5-speed transmissions.


Specifications


OEM
34191-79E


Pack
1


HS Code
8714102000


Origin
US


Motorcycle family
Dyna | FXR | Softail | Touring