My electric fan doesn't seem to kick in; my temperature gauge doesn't work, and I'm not riding the bike, but just letting it idle, so I don't want to overheat it, but how long should it take for the fan to kick in from idling? I want to make sure my fan motor switch is good.

 

Check this post: https://cbrforum.com/forum/cbr-600f2-16/cbr-f2-thermostat-106064/

From just idling, if I had to guess... maybe 8 minutes after startup, my fan might turn on? But basically it's whenever your coolant starts to boil.

 

yea man i had the overheating problem earlier this year with my bike. after riding it for a while and getting off. the bike would over heat after 4-5 minutes. most ppl can get away with it if they dont have much traffic. but yea wait about 5 minutes after riding and the fan should kick on. you shouldn't worry to much if it overheats. just turn it off immediately. the radiator cap should blow all the excess coolant into the reservoir and you would start to hear/see it boil. i think the temp gauge is kinda a necessity.