Picking the right primary fluid ensures the life and durability of your primary, that’s why BAKER recommends a 85W primary oil like the Spectro Heavy Duty Primary Oil. This Spectro SAE 85W viscosity helps eliminate any slipping or clutch drag.

Learn more about Spectro oils here: https://spectro-oils.com

Oil Capacity Detail

• BAKER Bully Primary Cover Fluid Capacity Dry: 38-45fl-oz
• BAKER Function Formed Primary Fluid Capacity Dry: 10-14fl-oz
• 2005-2010 Big Dog Motorcycles Primary Fluid Capacity Dry: 32 fl-oz
• Factory HD Primary Fluid Capacity
  •  1 Quart* (32 fluid oz) for all Evo and Twin Cam88/103 primaries from 1980-2006 (*except 2006 Dyna)
  • 45 fl-oz for 2006-up Dyna, 2007-up Softail & Touring if the entire primary assembly has been removed OR 38 fluid oz if you are simply draining the old fluid and adding new oil

Part Number