Radiator Fan issue

[stormoffires]

So from what I have read the radiator fan should kick on at or about 3/4 the gauge. well mine doesnt always come on and when it does seems to stay on for short bursts. could this be a relay issue? I have pulled it off and hooked it up to an external power source, it runs and blows air just fine (im assuming the fan is designed to blow air at the radiator?) I have noticed sometimes when i shut the bike off (if the fan is running) it will kick into a higher speed and sounds almost like a mini jet taking off. Im considering throwing the fan on a manual switch, would this cause issues? also what is telling the fan to engage? id assume a relay

[eaglerider]

The fan sucks air thru the radiator, not blows thru. The thermoswitch in the bottom of the radiator controls when the radiator comes on, then when the radiator cools, shuts the fan off. Sounds like u may have a thermoswitch that is going bad. a lot of members use a toggle switch to operate the fan...no problem, except do not forget to turn off the fan when u shut the bike down, or the battery will run down.