Temp guage shows different readings & cooling improvements

[Asudef]

When running, it's about half a gauges worth off. For example, it will be around the middle mark while running/idling but if I kill the engine with the key ON, its up near the red.

Is this normal or is my gauge done? Since it still works, which is the more accurate temp so I can keep an eye on it?

Its in a FZR400 frame and the radiator looks too tiny to be effective. There's also no oil cooler on it
I did some sleuthing online and found a few larger ones that might fit but would putting just a push fan be sufficient? I have the stock pull fan but the valve cover is right up against the radiator, don't suppose I could reverse the polarity to make it a push to put in front?

Pros and cons to each method?

[buzzawak]

Fist up maybe provide a picture so we can tell you if the radiator of original.
Is at any point the overflow boiling ?
How old is the radiator cap ?
I the start the engine and leave it running, does the fan eventually start spinning and then turns off after a while?

[Asudef]

I have both radiators and motors but its the 600 radiator thats installed although the fan isn't mounted because theres no room between it and the cam cover.

I know the cooling isn't sufficient at idle but wanted to check here if the gauge is working properly or not so I can replace that and the radiator together.

[buzzawak]

I have done the 600 engine in a 400 frame with 600 radiator.
You can get the fan to fit with a bit of modification.
In a nutshell, the lower radiator mount has to come out by 10mm and you need to mount the fan upside-down.
The end result is a tight fit but not touching the engine.

[buzzawak]

Heating up
Below 98C No continuity
above 105c Continuity

Cooling down

[buzzawak]

Heating up
Below 98c (208f) No continuity
above 105c (221f) Continuity

Cooling down
105 to 98c continuity
Below 98c no continuity