Z900 Modifications, for those who know...

[kampfzentrum]

Worked on my Z over the winter and did a number of mods (exhaust, ECU flash, fluids, coils, to name a few). I'm noticing that even though Wisconsin hasn't gotten really hot yet, my running temp gauge is 4 bars on a 70 degree day at good speeds (air bypass). Now, I don't remember the temp being up so high so I'm consulting the community and I've narrowed it down to two suspects: 1) the 2WDW ECU flash, or 2) the topping off of coolant.

So when I pulled my ECU I topped off my coolant. After my first ride I was notified that I overfilled it because it was running out of a breather hole until it leveled out. But my fear is that it is still too high and maybe not circulating correctly - I'm really unfamiliar with this platform. Otherwise, it was the ECU reflash which makes little sense to me.

Input dudes?

[RedRooster]

I changed coolant last fall. After filling the radiator, I filled the reservoir a little over the lower level line. Turned engine on and watched the reservoir tank closely. As the engine temp increased, the level in reservoir went up slowly and stopped before the upper level line (approx. 100ml).

As the temp increases in radiator, pressure increases which pushes some coolant into the overflow tube that runs to the reservoir tank. When engine cools, it gets sucked back up into the radiator. It is best to have the level in reservoir tank about half way between lower and upper level line (or a little less) when cold. At least that is how my system is working.

I recall when I purchased my bike, I mentioned to the salesman that the coolant level was only at the lower level line. So, he headed out to the service dept. to have them add a bit more coolant. The owner overheard this, and practically ran out to the service dept. to make sure they did NOT add coolant to the reservoir. He knew what would happen.

[RobZ900]

The temperature gauge on the 17-19 model isn’t really clear. In that sort of temperature, 4 bars is perfectly normal. The thermostat is set to kick the fan in at a certain temperature, but as we only have bars to go by, it’s 5 bars. The ECU flash generally lowers the kick in temperature of the fan in an effort to keep the bike a bit cooler, but unless you’re hitting 6 bars, I wouldn’t worry about it.

[RedRooster]

4 bars at 70 degrees on the move is normal? Not on mine, 3 bars at 70 degrees and 4 bars at 80 degrees and higher. And maybe a brief 5 bars in stop and go traffic when it's really hot, but returns to 4 bars when back to speed.

Engine temp has been discussed quite a bit, and it seems to differ amongst riders. Never did like those stupid bars, but I think RobZ is right and as long as you don't get 6 bars, it's okay.

[Cazzy_R]

 My coolant reserve tank has a yellow dot on it. That's the ideal level mark isn't it? 

[RobZ900]

Originally Posted by RedRooster

4 bars at 70 degrees on the move is normal? Not on mine, 3 bars at 70 degrees and 4 bars at 80 degrees and higher. And maybe a brief 5 bars in stop and go traffic when it's really hot, but returns to 4 bars when back to speed.

Engine temp has been discussed quite a bit, and it seems to differ amongst riders. Never did like those stupid bars, but I think RobZ is right and as long as you don't get 6 bars, it's okay.

In fairness, you’re probably right. Normally 3 bars on the move but jumps to 4 almost straight away if you slow down/stop. Then 5 bars if it’s hotter.

[porkchop]

Originally Posted by RobZ900

In fairness, you’re probably right. Normally 3 bars on the move but jumps to 4 almost straight away if you slow down/stop. Then 5 bars if it’s hotter.

Until it's pissing out antifreeze I ride it.

[Cazzy_R]

Originally Posted by kampfzentrum

....... I topped off my coolant.

 What with? 

[zed9]

I've only owned one other bike with a temperature gauge. It was a real gauge that showed the temperature in degrees. That thing moved so quickly from 170 to 230 degrees I thought there was something wrong with the bike.
It's not like a car which stays pretty constant. A bike has a physically small engine so it's going to fluctuate a lot.

[MaverickAus]

Mine sits around 70 degrees C