Fat Ass kit up to 360, for Milwaukee-Eight Softails 2018 and up

Gone are the days of gearbox and primary relocation, right-side drive gearboxes, frame modifications, welding work and any other unpalatable work associated with 300 mm tires in original Harley-Davidson frames.

With Rick’s new ‘Wide Tire Kit’ for Milwaukee-Eight Softail models, the swingarm fits into the original H-D stock frame and even a 360 tire runs centered.

The power distribution is via an intermediate shaft which sits at the pivot point of the swingarm.

Therefore motor and gearbox stay one unit, less strain is being created and no suspension forces have an effect on the belt. Since the primary box remains in the original location, the footrests don’t have to be repositioned and ground clearance and lean angle remain the same as on the stock bike.

To make mounting easier, the swingarm is prepared for different options (drive side brake, original brake caliper, side licence plate) and black polished plastic coated (matt black option possible).

Rick’s wheels are supplied with special hubs for this kit so that the wheel runs centered. With the different versions for the various Softail frames and engines, attention was paid to keep the original transmission.

In addition to the 18” swingarm kit, the system was also adapted for 10.5” x 20” with the Avon 280/40 R20 tire. The first complete swingarm kit for a 20” wheel in the OE Softail frame!

(2.1) The stock position of the secondary drive stipulates a maximum tire width.

(2.2) The cheapest way is to relocate the wheel center of the wide tire to the right, which results in negative ride performance.

(2.3) More elaborate: relocating the primary drive with elongated transmission shaft and an offset piece to the outside.As maximum length of the offset, 2 inches, about 5 cm, are recommended. Any longer and bearings in the motor block and transmission are being stressed too much due to the long lever trail. But also for this there is a solution with a further bearing to the left of the clutch, although all this increases the already excessive weight on the left side. Primary drive with offset have therefore also a negative influence on ride performance.

(2.4) The most original and cleanest solution of the weight problem on the left side is the “Right-Side Drive”, where the transmission is relocated to the right via the clutch on the left side. Here the weight ratio is balanced out. 
(2.5) German customizer Ricks offers a special solution: an intermediate shaft with a second secondary belt behind the swingarm housing relocates the transmission to the outside.




Text & Graphic Huber Verlag Mannheim | Alles über Rocker



  • no gearbox offset
  • no primary offset
  • no right-side drive
  • no disassembly of oil tank
  • no opening of gearbox
  • no engine offset
  • no increased pressure on crankshaft
  • no frame alterations
  • no welding necessary
  • 300 tires centered in stock frame
  • well balanced bike
  • fast installation
  • complete delivery from one supplier
  • Gates carbon fiber belt
  • TÜV approved
  • Made in Germany
  • patent protected

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Fat Ass kit up to 360, for Milwaukee-Eight Softails 2018 and up

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+49 (0) 7221 / 3939-0

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