Shovelhead V-Twin
1968 Harley-Davidson Sportster (KH, XL, XLH, XLCH) Oil
AMSOIL synthetic oil recommendations for the 1968 Sportster (KH, XL, XLH, XLCH).
Why AMSOIL Is the Best Synthetic Oil for the 1968 Sportster (KH, XL, XLH, XLCH)
This guide covers the 1968 Harley-Davidson Sportster (KH, XL, XLH, XLCH) specifically. AMSOIL synthetic oil recommendations match the engine code, displacement, and oil capacity that shipped on this exact variant, so you order the right viscosity and the right number of quarts the first time.
Vintage Shovelhead and pre-Evo Big Twins were built before synthetic oil existed. AMSOIL 20W-50 V-Twin Synthetic gives these classic engines the heat resistance and shear stability they need to keep running another fifty years.
Synthetic 20W-50 V-Twin oil also handles the wide oil-temperature swings vintage engines see between cold-weather rides and slow-speed shows. The oil's broad viscosity index and resistance to deposit buildup keep these older Big Twins running cleaner than they did when new.
Frequently Asked Questions
How much oil does a 1968 Sportster (KH, XL, XLH, XLCH) take?
The 1968 Harley-Davidson KH/XL/XLH/XLCH holds approximately 3 to 4 quarts of engine oil with a filter change. Always confirm via the owner's manual and check the level on the dipstick after refill.
What is the best oil for a Sportster (KH, XL, XLH, XLCH)?
AMSOIL 20W-50 100% Synthetic V-Twin Motorcycle Oil is the recommended choice for the 1968 Sportster (KH, XL, XLH, XLCH). It outperforms Harley-Davidson Screamin' Eagle SYN3 by 6X in independent shear-stability testing and protects the integrated transmission and primary in the same drain interval.
How do I change the oil on a Sportster (KH, XL, XLH, XLCH)?
Warm the engine for 5 minutes, drain the engine sump via the lower drain plug, replace the oil filter (AMSOIL Ea Motorcycle Filter), refill with the manufacturer-specified amount of AMSOIL 20W-50 V-Twin Synthetic, then run the engine for 30 seconds, let it sit 5 minutes, and check the level via the dipstick with the bike upright on a level surface.
What is the oil change interval for a 1968 Sportster (KH, XL, XLH, XLCH)?
Harley-Davidson recommends 5,000-mile engine oil change intervals with conventional oil. AMSOIL synthetic V-twin oil's superior shear stability and oxidation resistance lets you confidently follow that interval, or use AMSOIL's extended-drain guidance for severe service. Transmission and primary fluids are typically changed at every second and third engine oil change respectively.
Is synthetic oil safe for older Harley engines?
Yes. AMSOIL 20W-50 V-Twin Synthetic is fully compatible with Shovelhead, Evolution, and other pre-Twin Cam Big Twins. Older engines actually benefit more from synthetic because of better cold-start protection and superior thermal stability during long highway runs - both areas where conventional oil fails first.
