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Normal.

The temperature gauge displays the range of expected operating temperatures. The midpoint is selected to correspond to the nominal design operating temperature.

If you're at speed on a warm day you should expect to see temperatures between the gauge midpoint and three-quarter point, (usually 100°C for water-cooled bikes) where the maximum gauge reading indicates the boiling point of a pressurized 50/50 mix coolant, the temperature at which the pressure relief cap will likely discharge coolant to the overflow tank.

When you get stuck in stop-and-go traffic, the temperature will naturally begin to rise because now there is reduced airflow through the radiator cooling fins. During these traffic conditions, temperatures in the upper quarter of the gauge display should be EXPECTED and not necessarily be a cause for alarm or an indication of cooling system problems.

If it gets too hot your Ducati's fuel injected engine management computer automatically retards the engine ignition timing so as to run well at this higher temperature, but at a reduced power output.

An engine should be at its design operating temperature to make good power. Higher temperatures are more thermodynamically efficient, but run at too high a temperature and you exceed the thermal expansion design basis of critical components and raise fuel octane requirements.

Ducati fuel injected motorcycles use engine management computers incorporating a coolant temperature sensor to retard the engine ignition timing to compensate for any increase in octane requirement when operating temperatures increase. Retard the timing and you reduce power.

Most stock-engined sport bikes are designed to produce their best power when coolant temperatures are close to 200°F/95°C.

Duane Mitchel reported that he ran a series of tests to establish optimum running temp for a race bike and found that (185F) 85ºC is perfect. Over that, they lose horsepower fairly quickly (down about 15 HP at 100ºC) and below that the same (down about 6 HP at 65ºC).

One thing that you can do to reduce operating temperatures is to straighten out any bent radiator fins and cover them with protective screening.

This is an easy do-it-yourself project for a superbike. After you straighten any bent radiator fins, cut a piece of aluminum window screening to fit leaving 4-5 inches on top to make some tabs to bend over the top and back of the radiator. It conforms easily to the curved radiator shape and the wind pressure holds it firmly against the radiator.

Remove the V-shaped lower cowl and attach another piece of screen to protect the oil cooler. Fasten it to the back of the panel with small self-tapping screws and washers at the four molded holes.*Silicone adhesive or double-sided tape also works.

Any screening will reduce airflow somewhat, of course. The smaller the mesh, the more protection against smaller debris. I can only offer that common aluminum window screen works fine in desert temperatures with no noticeable effect on 916 coolant temperatures.

I wish I thought of it right away before fin damage occurred. After 20,000 miles, I still haven't had to replace it. I used window screening simply because it's cheap to replace and has a fine-enough mesh to spread out the impact load (and keep bugs out), but if you prefer something different, check out the McMaster-Carr web site. When they sell mesh screening, they define the percent open area that tells you about its ability to flow air.

If you want even lower coolant temperatures, change from a ethylene glycol/water 50/50 coolant mix to WaterWetter and water, but I caution you that this will often make the bike run at temperatures below the gauge midpoint, too cool for efficient operation.