675 Charging problem

I have a strange problem, the bike charging system works perfect including the rectifier and battery.

When the bikes reaches optimum temperature or I say when the cooling fan starts to run the battery drains out completely but again strangely when the bike cools down for about 10 to 15 mins, it's starts again.

I just can't find a solution for this. Please help.

 

A faulty battery that gets hot will drain and then recover as it cools

 

I have changed many batteries but facing the same problem.

 

You say the fan cuts in at opt temp but does the fan then go off or is it running continually

 

It does go off, it runs the way it should. How many bars should the temp gauge show when the engine gets hot or when the fan starts to run

 

As a rough guide you should always see 2 unlit segments at the top poss 3 when riding. But if you leave the ignition on without the engine running and the fan on this will flatten the battery.

 

I'm no electrician, so am probably totally wrong here, but if the battery drain only comes on when fan is on then is ok when fan is off, I'd look at wiring from thermostat to fan. Or thermostat switch thingy