From an engineering standpoint, it is difficult to design a machine or mechanism that achieves multiple objectives with minimal compromise. An amphibious car is a good example. A few have been manufactured over the years, and they achieved the goal of navigating on land and water, but did neither very well. On the other hand, a Swiss Army knife achieves multiple objectives with minimal compromise. You can snatch the cork out of a wine bottle or kill somebody all with the same widget. The DD6, or Direct Drive 6-speed, combines 3 technical approaches to achieve the most advanced transmission gearset design available for your Big Twin with minimal compromise. First, 1st through 3rd gears are straight cut (spur) for strength during maximum acceleration with no parasitic axial thrust. Secondly, 4th and 5th gears are automotive style helical gears for quiet and smooth operation as highway speed approaches. Lastly, 6th gear is direct drive which means there is no underdrive or overdrive in top gear which translates into 99% efficiency for minimum parasitic loss, minimum wear and tear, and maximum fuel efficiency. But we didn’t focus solely on the gearset, we made this sucker shift like glass. The sequential motion of the hard chrome plated forks is controlled by a fixed spindle radial ball bearing mounted shift drum. Hard chrome guarantees long fork life with minimal imposed friction on the fork groove of the gear. The fixed spindle drum design eliminates any chance of binding or imposed friction about the axis of drum rotation. Drum rotation is controlled by a roller detent and actuated by a BAKER shift pawl with a anti-overshift feature. To make finding neutral an easy chore, we mounted a redundant detent on the left side pillow block.
Bearing Door Type: All DD6 bearing doors have the same outer profile as a stock 5 speed so exhaust brackets, torque arms etc. fit like stock. The DD6 door comes with or without an ear. The ear door is for exhaust bracket mounting and does not fit 1993-2006 FL applications.
All DD6 bearing doors have the same outer profile as a stock 5 speeds so exhaust brackets, torque arms etc. fit like stock. The DD6 door comes with or without an ear. The ear door is for exhaust bracket mounting and does not fit 1993-2006 FL applications. Note the images below. The DD6 door bearings are larger providing 25% more dynamic load capacity than stock bearings used through 1998, also uses a 1/8″ bearing retainer plate instead of stock style snap rings.
DD6 Bearing Doors
DD6 vs. Stock Comparison
FL Case Differentiations
To see an illustrated example of the differences between FL cases by year, please open the PDF here.
All DD6 gearsets are made out of 8620 steel, gears are shaper cut before heat treat then precision ground with diamond coated tooling after heat treat (58-62 Rockwell ‘C’). This extra steps ensures not only a quieter gear pair, but enables much tighter backlash control. The gearset is a combination of helical and spur gears to yield silent gear operation. The dog teeth are backcut at a 1° angle to optimize the smooth shift possible, while standard gearsets are cut to a 4° angle. The mainshaft is unique with 1st main gear being incorporated as part of the shaft, the countershaft also features a unique 1-piece design with 6th gear.
Available No Cost Options
Available at an Additional Cost
27T Comp Sprocket, available on FL models for a more aggressive primary ratio. Not compatible on Softails or Dyna models due to the inner primary design.
The DD6 comes in a stardard 3.24 or optional 2.94 1st gear
Standard Ratios- shown above are without the 28 tooth comp sprocket
Effective Ratios- shown above are with the 28 tooth comp sprocket
Builder’s Kit Part Numbers
All Part Numbers Listed Are Standard (Effective) Gear Ratios
|DD411L||DD6 Builder’s Kit||1990-97 Softail1991-97 Dyna|
|DD411||DD6 Builder’s Kit||1990-94 FXR1990-97 FLT-FLH|
|DD411SL||DD6 Builder’s Kit||1998-99 Softail1998-00 Dyna|
|DD411S||DD6 Builder’s Kit||1999 FXR1998-00 FLT-FLH|
|DD411PL||DD6 Builder’s Kit||2000-06 Softail2001-05 Dyna|
|DD411P||DD6 Builder’s Kit||2001-06 FLT-FLH|
Builder’s Kit Notes
Complete Build Notes
The BAKER Softail case design had all leak potentials in mind during the design. We added stud pads to the inside of the case so that the thread holes for the transmission studs were blind holes, NOT through holes like some aftermarket brands. Looking at the image on the right you can see the difference.
Compare the DD6
See the difference between other transmission kits and our DD6 and OD6. Click Here for a PDF file comparing our DD6 and OD6 gearset against other manufacturers.
Click on the image to Compare the DD6 and OD6 gearsets
Recommended Fluid / Level
Picking the right transmission fluid ensures the life and durability of your transmission, that’s why BAKER recommends a fully synthetic GL-5 rated gear weight oil of 75W-140. If a GL-5 rated gear lube is not available, these commonly carried viscosities (weights) will work 75W-90, 75W-140 and 85W-140. BAKER does not recommend the use of Syn3 (20W-50). For Bert’s article on ‘Oil & Spiders’ Click Here
DD6 installation instructions with exploded views: Click Here
These example finishes are intended to show the exterior treatments of cases, top covers and doors.
TERM AND CONDITIONS
LIMITED WARRANTY POLICY
BAKER™ transmission assemblies, transmission kits, primaries, and oil pans are guaranteed to the original purchaser to be free of manufacturing defects in materials and workmanship for a period of 5 years from the date of purchase or up to 50,000 miles. BAKER™ clutches, kicker cover kits, belt drives, F6F kit, reverse systems, covers and accessories are guaranteed to the original purchaser to be free of manufacturing defects in materials and workmanship for a period of 2 years from the date of purchase or up to 24,000 miles - whichever occurs first. If the product is found by BAKER™ to be defective, such products will, at the option of BAKER™, be replaced or repaired at cost to BAKER™.
In the event warranty service is required, the original purchaser must call or write BAKER™ immediately with a description of the problem. If it is deemed necessary for BAKER™ to make an evaluation to determine whether the transmission assembly or transmission kit or accessory is defective, the entire transmission assembly, whether originally purchased as an assembly or kit, must be properly packaged and returned prepaid to BAKER™ with a copy of the original invoice of purchase. If after an evaluation has been made by BAKER™ and a defect in materials and/or workmanship is found, BAKER™ will, at BAKER™ option, repair or replace the defective part of the assembly.
WARRANTIES FOR "INSIDER SPECIAL" PRODUCTS
Due to the uniqueness, low price and assembly outside of typical production process of products indicated as Insider Special products, purchasing these Insider Special products include a warranty so to guarantee the original purchaser to be free of manufacturing defects in materials and workmanship for a period of 1 year from the date of purchase or up to 12,000 miles. We have provided extended options for you to purchase below.
RETURNS AND EXCHANGES
Any merchandise returned for any reason (exchange, credit or modification) must be accompanied by a Return Goods Authorization (RGA) number or it will be refused. Call BAKER™ to obtain this number prior to returning goods for any reason. There is a 15% re-stocking fee for all returned items. BAKER™ is not liable for any shipping charges.
ADDITIONAL WARRANTY PROVISIONS
NOTE: Limited warranty does not cover labor or other costs or expenses incidental to the repair and or replacement of BAKER™ products.
This warranty does not apply if one or more of the following situations is judged by BAKER™ to be relevant: BAKER™ OEM transmissions; (these are subject to the OEM manufactures warranty only), Improper installation, accident, modification (including but not limited to use of unauthorized parts, transmission oils or lubricants), racing, high performance application, mishandling, misapplication, neglect (including but not limited to improper maintenance), or improper repair.
BAKER™ shall not be liable for any consequential or incidental damages arising out of or in connection with a BAKER™ transmission assembly, transmission kit, component or part. Consequential damages shall include without limitation, loss of use, income or profit, or losses sustained as the result of injury (including death) to any person or loss of or damage to property.
BAKER™ transmissions, transmission kits and accessories are designed exclusively for use in American V-Twin motorcycles. BAKER™ shall have no warranty or liability obligation if BAKER™ parts are used in any other application.
If it is determined that a BAKER™ product has been disassembled during the warranty period for any reason, this limited warranty will no longer apply unless you were instructed to do so by a BAKER Drivetrain technician for diagnostic purposes.
The words H-D®, Softail®, FXR®, Dyna®, FLT®, FLH®, Sportster®, and Buell® are registered trademarks and are for reference only.