Ducati.ms - The Ultimate Ducati Forum banner
  • Hey Everyone! Enter your bike HERE to be a part of this months Bike of the Month Challenge!

1 - 9 of 9 Posts

·
Registered
Joined
·
162 Posts
Discussion Starter #1
Hi folks,

As I prepare to get back from my ex-pat assignment I am looking forward to wrap up my 998FE project. I already wired a switch to manually trigger the cooling fans, but I wonder whether I can also source a thermostat which triggers the fans at lower temps.
Motowheels seems to make one for the 916/996 series, but not for the Testastretta engine. Anybody got any leads ?

Thanks
 

·
Registered
Joined
·
656 Posts
I think Speedymoto (used to) make a kit. I have one on my 998, but I installed it so long ago I can't remember where I got it.
 

·
Registered
Joined
·
363 Posts
I just added an extra OEM fan to the left side of my bike. Got way to scared seeing my temp steadily climbing to 250 after being in some light traffic.

In real traffic, forget out it. I had my clutch give out once it got so hot, and then a myriad of problems with the bike after.
 

·
Registered
Joined
·
2,478 Posts
i have a spare radiator with 2 748 fans on that i put on my 998. cooled it better, but still got way hot in slow traffic. replaced it with a modified gsxr 1000 radiator, runs much cooler now
 

Attachments

  • Like
Reactions: jahjah

·
Registered
Joined
·
853 Posts
Ducati engineers sized the cooling system components and chose the cooling fans temperature setpoints to optimize the operating temperatures such that the engine can develop its best power over the widest range of riding conditions and ambient temperatures.

Lowering the these setpoints is counterproductive — it will NOT lower the maximum operating temperature that you experience at a stop, and will adds a 60 watts per fan electrical load to the charging system for longer durations — and more often — as you ride.

The 916 cooling system was designed to keep the engine coolant temperature at a specific operating point, 180°F, when moving at speed on a hot 90°F day. This is the operating condition that is used to size the radiator, water pump and hoses. The overall design is based on the use of a 50/50 mixture of ethylene glycol and distilled water. If you use a different coolant or mixture percentage you change the design operating temperature.

The 998s have the same cooling system components but revised (less effective) fairing cooling vents and an additional radiator fan. The computer turns the fans on (LH) at 214°F, (RH) at 216°F.

The most common 998 gauge temperatures experienced are 210°F at speed and 250°F in traffic on a hot day. Substituting Water Wetter/water for the glycol/water coolant drops these numbers to 200°F and 220°F respectively. One owner checked the accuracy of the OEM gauge and found that it read 15°F high.

Typical 998 Operating Temperatures on a 90°F Day

200°F @ speed with WaterWetter/water
210°F @ speed with 50/50 glycol/water
220°F @traffic stop with WaterWetter/water
250°F @traffic stop with 50/50 glycol/water

When you get stuck in stop-and-go traffic, the temperature will begin to rise because now there is reduced airflow through the radiator. At around the three-quarter point on the gauge, the radiator fans kicks-in to provide the needed airflow. The fans stay on above this temperature. With the fan operating, when the temperature drops to just above the gauge midpoint, the fan stops running.

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 your 998 is not discharging coolant it's not overheating.

Most stock-engined water-cooled sportbikes are designed to produce their best power when coolant temperatures are close to 200°F.

The problem with our bikes is they run at the correct temperature at speed, but get hot at low speed. This tells us that the radiator is big enough but the airflow (cubic feet per minute) through it isn't enough at the lower speeds. Hence the need for auxiliary fans.

Ducati fans aren't very big or efficient but adding a shroud will improve airflow. See davy.j's solution:

http://www.ducati.ms/forums/56-superbikes/84130-what-s-better-coolant-method-999-a-3.html#post816713

Finally, check the radiator for damage from road debris. Carefully straighten any bent fins that restrict airflow.
 

·
Premium Member
Joined
·
5,151 Posts
hallelujah brother. been trying to tell people for years the 9 series ducati had good cooling systems. good enough that they used it in the 10 and 11's. if you have overheating problems it because there's something wrong with your bike.
 

·
Registered
Joined
·
2,478 Posts
it is funny how ducati uses the same radiator for a 748 as they do for a 998. my 748 never overheated or blew a tank, my 998 got hot all the time and blew two tanks. the bigger the motor the more heat is generated and better cooling is needed. my 998 runs great with the larger radiator, gets up to 190 in the summer instead of 210 or higher.
 

·
Registered
Joined
·
3,950 Posts
My 748 blew a tank, twice. The 916 never did nor did the 996 which is not treated very delicately. Tanks are tanks. Some go, some don't.

The 748 sat at 210 on the highway w/ no traffic in the summer. The 748 pegged at 250 a few times in traffic.

It's time to get over the 210 and up issue because it is not an issue. If you cannot get over it psychologically, then feel free to spend money were it does not need to be spent.
 

·
Premium Member
Joined
·
5,151 Posts
The tanks go because if fatigue. I've been lucky or I've lived a sheltered life. In all my years I've only ever replaced 3 tanks. None of which were mine and I've had 9 water cooled dukes.
 
1 - 9 of 9 Posts
Top