Bike Not Charging When Fan Comes On, Fine Otherwise

[nscuba]

Hi

2001 VFR

I have recently replaced the stator/RR/and battery, along with a vfrness. Stator and RR are Ricks. All seems to be working well, until the bikes in traffic and the fan kicks on. After this occurs, the voltage which would normally be over 14 at 2000rpms, is about 13 and doesn't rise much more until the RPM are 5K. After being in traffic for a while it will only reach 13V regardless of RPMs.

Checked stator output and all is good.

In trying to diagnose this, I've narrowed it down to the fan. When the bike is hot and the symptoms arise, if the fan is disconnected everything works fine again. When the fan is activated manually, the voltage drops and symptoms reappear

With the bike not running, and the fan activated the voltage doesn't drop much 0.4 V or so. Tested this with key on but bike not running. This doesn't seen out of place.

Has anyone come across this before. Seems unusual the fan coming on would affect the RR output, or draw so much the voltage drops over a volt.

Any input appreciated. Also checked the orange ground block, and its in great shape. All have continuity to ground.

Battery was tested, and tests as new. Which it was.

[TNRabbit]

That is unusual that it would drop when running but not so much when off....

[jeffyjeff]

In my experience, '98 VFR and '00 VFR, this is normal. The current draw from the fan plus all the other electrical components on your bike is too much for the stator to support, so the voltage drops. This is a result of the stator's limited output, the regulator is giving the bike all its got, but its not enough. Soon as you start moving and increase the airflow through the radiators, the coolant temp drops and the fan turns off...up comes the voltage.

It's normal. The bike is not made to have the fan on for extended periods. Jeff J.