Oil Tanks

About Oil Tanks

Some engines keep their oil in a separate tank instead of the crankcase sump, and the Harley-Davidson Sportster and FXR models listed here are examples. A tank is replaced when it leaks at a seam or fitting, is dented, or when a build or restyle calls for a different finish.

The tanks shown are chrome for the FXR and gloss black for the Sportster, so match the tank to the model and frame. Check that the fittings for the inlet, outlet and vent are in the same positions as on your old tank, so the oil lines connect. Weld-on gas and oil tank tabs are also listed for custom builds, and welding should be done by someone who knows the work.

Brands here are Drag Specialties and LA Choppers. After a tank change, inspect the lines and clamps. For fasteners and brackets, see Brackets & Hardware. The wider group is Engines & Engine Parts.

FAQs on motorcycle oil tanks

What is a dry-sump oil system?

In a dry-sump system, a pump moves oil between the engine and a separate tank rather than storing it in the crankcase. The tank holds the oil supply and is checked and filled separately, following the manual for your model.

Do I need new oil lines when I replace the tank?

Inspect them. Cracked, hardened or swollen lines and tired clamps should be replaced, because a leak at the tank connections is a common problem. Check that the fittings on the new tank match the lines before you start.

How do I fill and check oil after fitting a new tank?

Fill to the level the manual gives, start the engine so oil moves into the lines and engine, then recheck the level and look for leaks. The correct check procedure for your model is in the manual.

What are weld-on oil tank tabs for?

They are mounting tabs for fabricators building custom tanks or frames, giving a place to bolt the tank down. They need to be welded on, so they suit builders with the right equipment and experience, not a bolt-on job.