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.
Features
Billet 6061-T6 bearing door
1/8″ thick bearing retainer plate
Helical & spur gear design gear for quiet operation
28 tooth comprocket forged out of 8620 gear steel
Regina® double row primary chain
All transmission seals, gaskets and hardware
5 Year limited warranty
Benefits
Smoother shifting
Positive, certain shifting
Easier-to-find neutral
Quieter operation
More-efficient torque-handling
Fitment
1990-97 Softail
1991-97 Dyna
1990-94 FXR
1990-97 FLT-FLH
1998-99 Softail
1998-00 Dyna
1999 FXR
1998-00 FLT-FLH
2000-06 Softail
2001-05 Dyna
2001-06 FLT-FLH
***PLEASE CALL 517-339-3835 FOR SCREAMING EAGLE 6-SPEED TRANSMISSION APPLICATIONS.
***PLEASE CALL 517-339-3835 FOR 12MM MAINSHAFT (FOR WIDE TIRE APPLICATIONS)
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. * Limited supply of chrome bearing doors with ear available. Please give us a call at 517-339-3835 to order a chrome bearing door.
DD6-411-02
DD6 Builder's Kit, 1990-1994 FXR, 1990-1997 FLH-FLT, 3.24 1st Gear, Polished No Ear Door, Standard Shift Pattern
Bearing Door 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. * Limited supply of chrome bearing doors with ear available. Please give us a call at 517-339-3835 to order a chrome bearing door.
DD6 Bearing Doors
DD6 vs. Stock Comparison
Redundant Neutral System
Shift System Our 6 Speed shift system with roller detent guarantees smooth shifts every time and our redundant neutral ensures that finding neutral is a easy chore. We mount a plunger detent on the left side pillow block and cut a plunger track into the shift drum itself. The plunger follows this track during operation (shifting) and when shifting into neutral pops into a pocket. This system lets you feel that you’re shifting into neutral. No more guessing. Shift drum features more aggressive timing on the fork groove profiles and is case hardened to 58 Rockwell for wear resistance and crisp shifts. We built our reputation on smooth shifting 6-speed transmissions; our drum designs benefit from the engineering lessons learned.
FL Case Differentiations To see an illustrated example of the differences between FL cases by year, please open the PDF here.
Gearset 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.
DD6 Gearset Layout
Gears and Shafts Design
DD6 Shift Forks
Shift Forks Our shift forks are made out of billet steel then dipped in a hard chrome plate bath for wear resistance, also designed with oil reliefs to ensure proper lubrication and wear resistance on fork blades and shift dogs.
Available No Cost Options
Standard Shift Drum (1-N-2-3-4-5-6)
N1 Shift Drum (N-1-2-3-4-5-6)
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 standard 3.24 1st Gear.
Standard
Ratios
1st Gear
3.77
2nd Gear
2.56
3rd Gear
1.87
4th Gear
1.44
5th Gear
1.15
6th Gear
1.00
Effective
Ratios
1st Gear
3.24
2nd Gear
2.20
3rd Gear
1.61
4th Gear
1.24
5th Gear
.99
6th Gear
.86
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 Notes
The DD6 is not designed to be used in conjunction with belt drive primaries,auto chain tensioners or easy pull clutch kits.
Recalibration Box PN 95E-56B
Special Note
Speedo recalibration unit is required for electronic speed sensor applications; PN 95E-56B.
A + 12MM mainshaft length is available for wide tire applications. (Call us to ensure ordering accuracy)
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 Upgrade
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
Installation Instructions DD6 installation instructions with exploded views: Click Here
Warranty
TERMS AND CONDITIONS
BAKER Drivetrain reserves the right to change prices, terms or policies at any time without notice. Orders can be pre-paid using Visa, MasterCard, American Express, Discover or PayPal. All orders not pre-paid will be sent C.O.D. certified check or money order only unless pre-approved for company check acceptance. Any orders from outside the USA must be pre-paid in US funds via wire transfer; a $30 transfer fee will apply. Prices shown are F.O.B. Haslett, MI.
LIMITED WARRANTY POLICY
BAKER™ transmission assemblies and transmission builder 's kits, 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, whichever occurs first. All other BAKER products 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, except for the following; Warranty does not cover clutch plate wear, throw out bearing failures or mainshaft breakage due to improper clutch nut installation.Electrical components carry a 30-day warranty; cosmetic finishes (chrome plating, hard anodizing, powder coating) are covered for 60 days. Certain promotional products may carry a shorter warranty as specified at the time of purchase. 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 purchase invoice. If after evaluation by BAKER a defect in materials and/or workmanship is found, BAKER will, at their option, repair or replace the defective part of the assembly.
RETURNS AND EXCHANGES
Returns are permitted within 30 days of the delivery date. 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.
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 manufacturers 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.
What model motorcycle do you ride?1998 Heratage Springer
DD6 3.24 first in FLSTS
Shipping was fast. Great customer support.Great quality transmision. Installed with 3.24 1st in 1998 FLSTS Makuni carb,andrews ev23 cam. I'm very happy with this upgrade to my 98. First thru fifth no change in power or RPMs but ohh that 6th gear is nice.
I had an excellent experience with my sales person She went far beyond what was necessary to help me.. she is a for sure keeper As for the product I still have not installed it yet but will be getting after it soon.
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Description
Features
Fitment
Detail
Warranty
Description
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.
Features
Billet 6061-T6 bearing door
1/8″ thick bearing retainer plate
Helical & spur gear design gear for quiet operation
28 tooth comprocket forged out of 8620 gear steel
Regina® double row primary chain
All transmission seals, gaskets and hardware
5 Year limited warranty
Benefits
Smoother shifting
Positive, certain shifting
Easier-to-find neutral
Quieter operation
More-efficient torque-handling
Fitment
1990-97 Softail
1991-97 Dyna
1990-94 FXR
1990-97 FLT-FLH
1998-99 Softail
1998-00 Dyna
1999 FXR
1998-00 FLT-FLH
2000-06 Softail
2001-05 Dyna
2001-06 FLT-FLH
***PLEASE CALL 517-339-3835 FOR SCREAMING EAGLE 6-SPEED TRANSMISSION APPLICATIONS.
***PLEASE CALL 517-339-3835 FOR 12MM MAINSHAFT (FOR WIDE TIRE APPLICATIONS)
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. * Limited supply of chrome bearing doors with ear available. Please give us a call at 517-339-3835 to order a chrome bearing door.
DD6-411-02
DD6 Builder's Kit, 1990-1994 FXR, 1990-1997 FLH-FLT, 3.24 1st Gear, Polished No Ear Door, Standard Shift Pattern
Bearing Door 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. * Limited supply of chrome bearing doors with ear available. Please give us a call at 517-339-3835 to order a chrome bearing door.
DD6 Bearing Doors
DD6 vs. Stock Comparison
Redundant Neutral System
Shift System Our 6 Speed shift system with roller detent guarantees smooth shifts every time and our redundant neutral ensures that finding neutral is a easy chore. We mount a plunger detent on the left side pillow block and cut a plunger track into the shift drum itself. The plunger follows this track during operation (shifting) and when shifting into neutral pops into a pocket. This system lets you feel that you’re shifting into neutral. No more guessing. Shift drum features more aggressive timing on the fork groove profiles and is case hardened to 58 Rockwell for wear resistance and crisp shifts. We built our reputation on smooth shifting 6-speed transmissions; our drum designs benefit from the engineering lessons learned.
FL Case Differentiations To see an illustrated example of the differences between FL cases by year, please open the PDF here.
Gearset 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.
DD6 Gearset Layout
Gears and Shafts Design
DD6 Shift Forks
Shift Forks Our shift forks are made out of billet steel then dipped in a hard chrome plate bath for wear resistance, also designed with oil reliefs to ensure proper lubrication and wear resistance on fork blades and shift dogs.
Available No Cost Options
Standard Shift Drum (1-N-2-3-4-5-6)
N1 Shift Drum (N-1-2-3-4-5-6)
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 standard 3.24 1st Gear.
Standard
Ratios
1st Gear
3.77
2nd Gear
2.56
3rd Gear
1.87
4th Gear
1.44
5th Gear
1.15
6th Gear
1.00
Effective
Ratios
1st Gear
3.24
2nd Gear
2.20
3rd Gear
1.61
4th Gear
1.24
5th Gear
.99
6th Gear
.86
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 Notes
The DD6 is not designed to be used in conjunction with belt drive primaries,auto chain tensioners or easy pull clutch kits.
Recalibration Box PN 95E-56B
Special Note
Speedo recalibration unit is required for electronic speed sensor applications; PN 95E-56B.
A + 12MM mainshaft length is available for wide tire applications. (Call us to ensure ordering accuracy)
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 Upgrade
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
Installation Instructions DD6 installation instructions with exploded views: Click Here
Warranty
TERMS AND CONDITIONS
BAKER Drivetrain reserves the right to change prices, terms or policies at any time without notice. Orders can be pre-paid using Visa, MasterCard, American Express, Discover or PayPal. All orders not pre-paid will be sent C.O.D. certified check or money order only unless pre-approved for company check acceptance. Any orders from outside the USA must be pre-paid in US funds via wire transfer; a $30 transfer fee will apply. Prices shown are F.O.B. Haslett, MI.
LIMITED WARRANTY POLICY
BAKER™ transmission assemblies and transmission builder 's kits, 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, whichever occurs first. All other BAKER products 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, except for the following; Warranty does not cover clutch plate wear, throw out bearing failures or mainshaft breakage due to improper clutch nut installation.Electrical components carry a 30-day warranty; cosmetic finishes (chrome plating, hard anodizing, powder coating) are covered for 60 days. Certain promotional products may carry a shorter warranty as specified at the time of purchase. 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 purchase invoice. If after evaluation by BAKER a defect in materials and/or workmanship is found, BAKER will, at their option, repair or replace the defective part of the assembly.
RETURNS AND EXCHANGES
Returns are permitted within 30 days of the delivery date. 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.
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 manufacturers 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.