The 6 Speed Overdrive transmission is the latest in torque multiplication technology and in fact the strongest and most reliable available to date. Zodiac based the 6 Speed Overdrive transmission on their race proven 5 Speed design. Unlike your stock transmission, which has a 1:1 ratio in top gear, this transmission gives you a 1:0.86 gear ratio in 6th speed. This means less RPM to drive at the same speed, resulting in less vibration, less wear and tear, and better fuel economy. The Zodiac Six Speed features an improved shift system over the stock 5 Speed. The shift drum is not a cast part but a CNC produced precision part. The drum fork pin grooves have a more exact shifts, the plunger/compression spring detent system has been upgraded with a late style roller/torsion spring for smoother shifts, and the dynamic load rating of the shift drum bearings has been increased 100% for improved radial loading characteristics. The gears are as wide as in your stock 5 Speed transmission with an added "beefy" 6th gear for the main shaft and a one-piece 6th gear/counter shaft unit. All of this for uncompromised torque capacity and strength. Zodiac 6 Speed overdrive comes with a billet aluminum trap door. The complete 6 Speed transmissions are available for Softail in a black Delkron housing or our reinforced and economical priced polished Softail housing, as well as for 1990-1994 FXR in Delkron housing. Other models and years can be built to order. The Zodiac transmission is stronger than anything available at present. The Zodiac gears are machined from Ultra Strong 20ChMnT High stress gear steel. This steel has superior strength over any other gear steel used in the aftermarket. Gears and shafts are tempered and stress released. The complete and ready to bolt-in 6 Speed transmission is based on the stock 5 Speed design, meaning there are no installation problems or frame modifications needed. The billet trap door features the electronic speed sensor hole, which can be plugged off (plug included), if a front wheel driven speedo is used. Offset transmissions come complete with all parts to offset the primary.

Note: Unlisted 6 Speed Transmissions for FXR and Dyna models can be built on special order. Delivery time is approx. 10 days.

Note: The use of an electronic speedo on a 6 speed transmission on 1994 to present models may require the use of a recalibration unit such as ZPN236690 or 236082.