You use 20w50 in the primary not gear oil for a 96 sportster 883?
That is not correct. You should not use 20w50 oil in the primary of your 1996 Sportster 883. The primary case of a Sportster 883 uses SAE 90, 75W-90, or 80W-90 primary gear lube that meets Harley Davidson's recommended specs. Using the wrong type of oil in the primary case can cause damage to the transmission gears and other components. It's important to follow the manufacturer's recommendations for oil type and viscosity to ensure proper lubrication and performance of your motorcycle.