Fan Switch:
Lower Temperature Actuation
While cruising down the highway, autobahn, interstate or operating your bike
at moderate speeds, the stock cooling system on most all current bikes will keep
engine coolant temperature under control.
Under control, means below 212f / 100c and above 86c.
Most stock engined sportbikes produce maximum power between 92c and 96c
coolant temp.
The lower end of that window is controlled by the thermostat. The upper end in
the cooling system's ability to shed heat.
Problems occur, though, when the bike is operated in town, in stop and go
traffic on hot days. There is insufficient air going through the radiator to remove
the excess heat.
The stock auxiliary cooling fans turn on commonly at ~100c, adding some
airflow and cooling.
That's too hot for most bikes to even run properly in town. Both TL 1000's
and RC51's are VERY sensitive to temperatures over 100c - running very poorly at
part throttle when hot.
When the coolant temp reaches a particular level, the fuel injected bikes will
then begin to tune themselves into "self preservation mode".
regardless of whether there's a mechanical problem or it's just that a racebike
is being used in an extreme environment - like idling in traffic on a 100f day!
TL1000's, as a typical, normal, everyday example, get rich and lumpy at 202f to
203f. You can feel the engine change it's running characteristics as you sit
there - and you can tell that it's reached that coolant temperature by the way
that it idles, even.
The TL, I only used as an example - every stock ECU that I've ever tested does
the same thing at some temperature.
The soon to be released Teka EMS can address the coolant compensation map, as
some bikes (as of 05/31/02) have relatively poor maps.
Changing the stock thermostatically controlled fan switch to a new
switch that completes the contact at a lower temperature will start
cooling the engine earlier and help prevent overheating when in town.
Now........ - Do I know all the part numbers? Nope!
You'll have to do some parts matching up from auto supply.
Look up your fan switch temperature in the service manual and then locate a
similar construction fan switch for a car that works at a lower temperature.
The sensors are pretty common.
DON'T call me or email me and ask where to get a lower temp. fan switch for
your bike - I'm not going to look it up - It's up to you to find it yourself.
|If you do the research and installation and you have part numbers, thread pitch
and diameter of the fan switch threads, I'll post the information and give you
credit for the research, though!
Good luck!
Marc
Look at your "fan on" spec:
The BORG-WARNER TFS-545 comes on at 205-208 and goes off at 195.
|