mga bro, greetings!

got a prob with my temp gauge. last time sumasabay cya sa rpm then bumalik sa normal. this time wla cya prob as long as ur running below 100kph but if you keep ur speed sustained above 100kph for a period of time and of course sa nlex ko lang nagagawa to, eh tumataas na cya pero weird kc pag ineutral ko cya while running e bumababa din cya. wori ko lang kc na mareach nya max temp reading while running dba coz ishutdown ng comptr box ang engine for safety. i need your help mga bro if you have any idea to solve this problem. thanks!