MXA TEAM TESTED: MOTO HOSE’S KAWASAKI KX450 RADIATOR Y-HOSE KIT

WHAT IS IT? Moto Hose redesigned its Works Y radiator hose kit for better flow and cooling while working with the stock radiators. Silicone has very high temperature and pressure ratings, allowing you to run higher pressures in the cooling system. You can also add personal flare to your machine with colors other than black.

WHAT’S IT COST? $399.99 (as tested). Prices start at $19.99 for various single hoses and kits for other applications.

CONTACT? www.motohose.com or (704) 340-7958. 

WHAT STANDS OUT? Here’s a list of things that stand out with the 2025 KX450 and KX450X Moto Hose Works Y radiator hose kits.

(1) Concept. The Moto Hose kit was designed to eliminate the cross-over tube in the stock system. The stock fittings have been replaced with two CNC-machined Moto Hose-designed aluminum fittings as well. The hose ends are tapered to the correct fit where required. The corners and angles are nice, and the “Y-hose” eliminates the system’s metal pipe and fragile Y-fittings. Each reduction of a fitting, a clamp, or a component is the elimination of a potential failure point. This setup also matches what Factory Kawasaki uses.

(2) Installation. Make sure the system is cool and unpressurized. The kit includes new hose clamps designed to be used with the silicone material. Be sure to torque all hose clamps securely, but not so tight as to cut or damage the hoses. It took our test rider 15 minutes to install the kit on our KX450. 

Step one is to drain the coolant via the lower water-pump bolt and remove the shrouds. Collect the used coolant for proper disposal or to reuse if clean and in good condition. The tools needed were an 8mm socket to remove the shrouds and drain bolt, as well as Phillips and flat-head screwdrivers and channel locks to remove the OEM hoses and install the Moto Hose kit. There are specific-sized hose clamps for the different diameter inlets that are specially made for silicone hoses. The hose clamps were stamped with Moto Hose lettering—a nice touch!

Step two is to refill the cooling system and purge the air from the system. Run the engine to operating temperature and inspect for leaks. Moto Hose provides an extra-long radiator overflow drain tube that can be cut and used to upgrade your fuel tank vent hose. 

(3) Pros and cons. Radiator hoses are often neglected. Most hoses are not replaced until they fail, which means a DNF, a long walk home, an overheated and damaged engine or, worse, an injury. The hose colors are nice and allow you to personalize your bike’s appearance. The drawback is you will need to work on your bike and replace components that seemingly work just fine. You must have the mindset that this is preventative maintenance.

WHAT’S THE SQUAWK? The price is high, but you’re paying for protection.

MXA RATING: Reducing potential failure points within a system is smart engineering. Peace of mind knowing you have aerospace-quality silicone hoses installed on your bike gives you the confidence to send it into the first turn.