Engine Cooling
About Engine Cooling
Engine cooling parts keep the engine inside its working temperature. On a liquid-cooled motorcycle, coolant is pumped through the engine, carries heat to the radiator and passes back again. Overheating, leaks and a drop in coolant level are the usual reasons riders come here, along with crash damage to a radiator and routine replacement of hoses and water pump parts.
The sub-categories follow the path the coolant takes. Radiators cool it, with Radiator & Coolant Reservoir Caps holding the system's pressure. Water Pumps circulate it, and many listings are rebuild kits, gasket kits and impeller covers. Pipes & Hoses carry it, and Clamps & Hardware hold the hoses in place. Fans & Fan Parts move air through the radiator. Oil Coolers & Lines are for cooling the engine oil, and the seals are in Gaskets, Seals & O-Rings. There is also Other Engine Cooling Parts. Most parts are model-specific, so pick your machine in the Ride Finder at the top of the page.
Brands in this section include Athena, Atlantis, DEI, Hot Rods and Vertex. The cooling system is part of the engine, so see also Engines & Engine Parts.
FAQs on motorcycle engine cooling
What are the warning signs of engine overheating?
Signs include a rising temperature gauge or warning light, coolant boiling over or leaking, a fan that runs constantly, a loss of power and steam. Stop the engine and let it cool. Do not open the radiator cap on a hot engine, since the pressure can cause serious burns.
What should I check first when a liquid-cooled bike runs hot?
Check the coolant level when the engine is cold, then look for leaks at the hoses, clamps, radiator and water pump. Also check that the radiator fins are not blocked with mud or bent, and that the fan runs when it should. Follow your manual for the coolant type.
Do hoses and clamps wear out?
Yes. Rubber hoses harden, soften or crack with age and heat, and clamps can loosen or rust. Squeeze each hose when the engine is cold, replace any that feel hard, spongy or swollen, and replace damaged clamps along with them.
Does an air-cooled motorcycle need an oil cooler?
Not necessarily. An oil cooler helps lower oil temperature and is often added by riders who tour, carry loads or ride in hot weather. It needs to be sized and routed correctly, so check the kit's fitment notes and your manual.
What is a water pump rebuild kit?
A water pump rebuild kit contains the wear parts of the pump, such as seals and bearings, so you can restore it without buying the whole pump. A leaking weep hole or a rough, noisy pump are common reasons. Kits are model-specific, so check the listing.
