Norton Motorsports Kawasaki Ninja 400 1.6 Bar High Pressure Radiator Cap

Typical small displacement motorcycles come with 1.1 Bar radiator caps. At 1.1 Bar pressure, a water/coolant mix boils somewhere around 259-260 degrees F. At 1.6 Bar pressure, a water/coolant mix doesn’t boil until roughly 280 degrees F.

So why is that important?

Track and race use can stress your motorcycle more than it was designed for on the street, and stress causes heat. Once your coolant reaches it’s boiling point, it will turn to steam and boil out of your radiator into your overflow. Steam cannot cool your engine fast enough, so your engine temperature can rapidly increase if you reach the boiling point of your coolant. Using a 1.6 Bar high pressure radiator cap gives you an extra 20 degree buffer to keep your coolant from boiling over and instead keep it in the radiator where it can cool the engine.

This simple and inexpensive upgrade will help keep your engine cooler when pushing it hard and keep your coolant from boiling over and spraying all over your bike and leathers.