Overheating
 

Hello eveybody! I'm new on here. I bought a ninja ex500d a few months ago which is in pretty good shape. Recently it started overheating and the fan stopped working. After some trouble shooting I came to find out that the fan works fine but the temperture switch was busted. I bought a used one from a shop that sells parts from old bikes. Got the perfect fit from an old ninja. Now, the fan works, but it kicks in when the temperature needle is just over half way and the needle slowly but surely continues to rise, whether in stop and go traffic or stationary. Now, I live in hawaii so it's warm out but it also happened at night. The temperature gauge should always be just below half and never over half way. It never heated like this before. Any suggestions? Any advice would be greatly appreciated!