Adding volume to a radiator via hoses and such.

Your bike does.

 

My r6 made the most power, over 190 degress on the Dyno.
If You're really curious is might be worth the Dyno time to find the optimal range for your engine.

 

theory vs real life results.
I'll take real life results all day, and twice on sunday .

 

They need not be mutually exclusive.

 

You may actually find that the more you understand about the principles involved, the closer these two things become to one another.

 

Where is the thermostat located in regards to in/out of the motor or radiator? I would think that it's possible that having a thermostat in could SHOW a lower temp but not actually lower the real running temp? Thinking that that the temp out of the motor could be higher while the temp in would be lower and if the sensor is on the in side (which wouldn't make sense as I type this) it would read off. Anyone following this?

 

Perhaps the water flows to such an extent with no thermostat that it creates cavitation and resulting lack of water actually interacting with the temperature gradient for heat transfer?

 

Two thermocouples and a couple hours of testing would put this one to bed.

 

nasty. why would you couple a couple with thermocouples in bed?

it's pretty obvious that there's lot's of friction, boiling over and leakage at the end of that test.

 

Be careful with changing engine operating temperature if your bike is computer controlled, ECU is looking for certain values from sensors for optimum fuel mixture... I supposed this can be massaged by tuning but I'm not a tuner...

 

190F is almost optimal for the most power. 170 will produce less power.You're good. If you have to race at altitude, you might need a bigger radiator.

 

This is much more a heat transfer problem than thermodynamics. And it isn't a given volume of water, it's a rate of fluid flow, which will be affected by the presence of a thermostat.

 

Interesting.
I always thought a cooler engine was prefered.
Hence the need for oil coolers, transmission coolers, cold air injection, etc (Auto reference obviously)

 

Might aught to look up the meaning of thermodynamics.....

Lack of a thermostat most certanly does have a direct impact on the ability of the system to cool properly.

 

this is almost certainly what got the OP started on this quest, and there's a very important distinction between the two things about what is cold: CAI is about the temperature of the air, and radiator efficiency is about the temperature of the engine.

we want air to be cold because colder air is denser air, meaning it carries more oxygen per unit of volume and can thus burn more fuel (and produce more energy) in the same size of cylinder.
we want the engine to be hot because the engineers designed its metal components to work perfectly together at a certain temperature and expansion size

 

Depends what you define "cooler" as... Cooler than 300 is definitely preferred... cooler than 180 not so much.

 

I've often wondered about this on race bike applications .. once a t-stat is open, and it's all the system can do to keep temp at 195F or below, do you need a t-stat from then on? is a t-stat nothing more than an aid to get the bike warmed up faster ?
Dirt bikes have no t-stat in most makes/models for instance..

 

Oil temperature is a completely different story. Cold oil is better. Air temp - cooler is better. On the dyno, and in correlation to the track, right around 190F water temp is max power.

 

Without the thermostat in place the fluid does not spend enough time for proper heat transfer to take place. IF the system is designed to operate with a thermostat. Always ran a thermostat on racebikes that came with one.
On the racecar we run a restrictor and also pulleys that reduce water pump speed by 30% from crank speed as well as a racing water pump, fan blade and shroud. 180 is the optimum temp for the race car engine. I would be happy with that on the roadrace bike also but have no issues with it being 190-200 either.
Honestly when the temp gets above 200 I’m more concerned with oil temp than water temp....

 

I’ve done a Vegas trackday that was so cold the water temp didn’t reach 195F. I bet the thermostat wasn’t fully open and was helping to increase temp. Tape over the radiator prob would have helped, and prob would have been required if the thermostat was removed.