Hey all, well I recently checked my coolant and it was quite low so i decided to go to the AAP near me and get some coolant among other things for maintenance. While there one of the guys who was helping me happened to be a life long bike mechanic and told me to try water wetter if my bike gets hot it will run 10-15 degrees cooler. Well I did it and all, but now my bike runs so much cooler than before it kinda worries me. Check out the pic:

http://img38.imageshack.us/img38/968/photoyvf.jpg


BTW this was after a 15 minute ride and the temp was ~90 degrees. It usually would have been a little bit less than halfway up.

We just had a cold front come through here, and now it runs even cooler than that. The temp is down about 20 degrees.

If it's not warming up at all..the thermastat is probably stuck open.

If your worried about the temp., I would flush the system and replace the t-stat. If your level was low and not from an over heating condition you should have just filled with coolant.

My EX-250 temp guage indicates about the same as yours.

It's a real toss-up as to the possible causes. You could do some investigation during a routine coolant change. I'm plannning to do my own detective work/coolant change on Thursday or Friday of this week.

Things to check out (once the coolant is drained) are:

#1. as CRXtrek mentioned, you could check to see if the thermostat is all crusted up and stuck open or just mechanically broken and stuck open.

#2. you can check to see if the temperature sensor is (also) all crusted up so it can't read water temp accurately.

If you had both of these situations going at the same time you would definitely run with cooler than normal temp guage indications.

The other possible issue I want to mention is that the EX-250 temp sensor is really an "el-cheapo" type sensor. It's a single-wire type sensor which means it grounds through the body of the sensor. The signal quality of a single-wire, body-grounded sensor is determined by it's connection to the piece of metal it's screwed into, which in this case is the EX-250's thermostat housing. This method of grounding a sensor typically results in a very noisy, jittery signal, so the manufacturer will only connect it to a highly damped guage.

The way the EX-250 temp sensor works is: the temp guage receives power from the bike's electrical system then it sends "reference-level voltage" down a wire into the temp sensor. The temp sensor is a Variable Resistance Thermistor which means that as it's temperature goes up it allows more of that reference-level voltage to go to ground (through the sensor body, into the metal of the thermostat housing). The temp guage senses this change as a decrease in resistance (a lower Ohm value reading) and produces a temperature reading based on that.

So, if the sensor isn't grounding well in the thermostat housing it can't send voltage into it as easily as it should, and that will result in higher than normal resistance which would give a false (lower than actual) temp reading at the guage.

Too much information?

Ok yea I understand, but according to the picture I provided it is definitely moving. I was just wondering if it wasn't heating up enough to running temp or if it could cause a problem.
Trey
Posted via Mobile Device

Gauge/sender may be failing. Disconnect the wire from the temp sending unit and with the ignition key on, touch the wire to ground. The gauge should peg at full scale.

You can also remove the sending unit and place it in boiling water with the wire still hooked up. See what the gauge reads then.

Last, but a little more work is to remove the thermostat and place in water with a thermometer. Heat the water to the thermostat's opening temperature and it should start to open at that temp and be fully open around 15-20 degrees hotter. If it's already open when you remove it for testing, you have your answer without further testing.

You could also block the radiator with a piece of cardboard and go for a short ride, but don't go far away from home!

Many things to try. Good luck! :)

I like g21-30's idea of puting a peice of cardboard in front of the radiator and going for a short ride. If the temperature starts to rise past its present position and continues to climb then I would pull over and remove the cardboard. This would indicate that the water wetter you put in is doing "too good" at cooling the engine.
Now to answer your question. As long as the temperature is between the second and third white lines there is no harm.

How do you even know what temp it is? That mark on the gauge might be 180deg?? or 200deg????

I like where its at in the pic BTW, much better than a higher mark.

My bike hovers around a little bit higher than that in hot weather with normal riding. If I'm stuck in traffic, of course, the temp gauge rises considerably.. In colder weather (~50 degrees) at constant speed, the needle is just about there. There are a lot of inconsistencies in these temperature gauges...

By the way, that oil light isn't always on, is it?

My bike hovers around a little bit higher than that in hot weather with normal riding. If I'm stuck in traffic, of course, the temp gauge rises considerably.. In colder weather (~50 degrees) at constant speed, the needle is just about there. There are a lot of inconsistencies in these temperature gauges...

By the way, that oil light isn't always on, is it?

no i took the pic RIGHT after a ride (still on the bike) with my iphone

Water Wetter does make a good difference.. I use it in my 500rwhp Mustang...

I'm not sure how much it affected the Ninja.. but then again there isnt much coolant in our bikes... I doubt your gauge or temp sending switch all of a sudden stopped working...

If you want it to warm up, just drive it slowly or let it idle.. the fan will kick on when it get 'really' hot.

no i took the pic RIGHT after a ride (still on the bike) with my iphone

What are you saying "No" to? The oil light being on? :confused:

What are you saying "No" to? The oil light being on? :confused:

He's saying no the light isn't ALWAYS on.

Since your temperature is withing the operating range, I'm not sure what you're worried about. You could go stop-go idle around in a parking lot for a while to see if the needle moves, which it should unless it's absolutely freezing outside. Much worse things that could be happening to your bike.

FWIW, from the Water Wetter website description:

"Does not lower cooling system below the thermostatically-controlled temperature." YMMV :)

Water Wetter does make a good difference.. I use it in my 500rwhp Mustang...

I'm not sure how much it affected the Ninja.. but then again there isnt much coolant in our bikes... I doubt your gauge or temp sending switch all of a sudden stopped working...

If you want it to warm up, just drive it slowly or let it idle.. the fan will kick on when it get 'really' hot.

Think our smaller cooling sytems depend more on it. I always thought coolant was coolant. While back I took the factory coolant out of the r1. With the factory stuff it would run 163deg, After the change high 170's. I changed the coolant out a number of times trying to get the 163deg back. Tried everything, different combos also. Waterwetter/antifreeze/water was the best, getting 171deg. I was about to change out the thermostat, but decided to try some factory coolant as a last test. The yamalube yamacool I put in, brought it back to 163deg :) They have to have something special in it for sure. I wonder if the Kawi stuff is the same????

FWIW, from the Water Wetter website description:

"Does not lower cooling system below the thermostatically-controlled temperature." YMMV :)

Well obviously...the coolant isn't moving to the radiator below the thermostatically controlled temperature. I'm not sure why my mileage will vary because of this though? :D

Well obviously...the coolant isn't moving to the radiator below the thermostatically controlled temperature.

:confused:

If the thermostat is closed, coolant is basically just floating around in the engine block. Until the thermostat starts to open above the thermostatically controlled temperature (aka, minimum temperature at which the thermostat start to open), the coolant will not make a trip to the radiator and back.

There's still some heat exchange going on at the engine, but I'm pretty sure it is relatively low compared to heat exchange at the radiator. So if the coolant is not using the radiator to cool it down, water wetter isn't really doing anything. Hence, it does not lower cooling system below the thermostatically-controlled temperature.

Make sense? :)

:thumbup: