i have this L reg fzr 400 and the battery runs flat after a while. i have replaced the battery with a new one, checked the charging, it shows a charge of 14v at tick over,14.2 at3500rpm. Put the lights on and volts drop to 12.4v at tickover,12.8v at 3500rpm.This seems i bit low i thought, any body know what volts i should be getting.

thanks cranny

Hi cranny

According to the Yamaha manual connecting a volt meter across the battery terminals and running the engine to 3000RPM you should get 14.3 - 15.3 volts with the lights off . Tony

According to the Yamaha manual connecting a volt meter across the battery terminals and running the engine to 3000RPM you should get 14.3 - 15.3 volts with the lights off . Tony

thanks tony,

mine is a bit on the low side then. I may have to try another rectifier,

Any body know how to check these charging systems.

thanks kevin

Usually if you get a faulty rectifier / regulator you will get a lot lower voltage then you have so i would check the connections and make sure they are clean and tight. You can test the stator coils in the generator by disconnecting the block connector with the three white wires coming from the engine and checking the resistances across the wires i.e three tests they should be within 0.44 - 0.66 ohms . If this checks out the manual then just says replace rectifier /regulator .Tony.

Usually if you get a faulty rectifier / regulator you will get a lot lower voltage then you have so i would check the connections and make sure they are clean and tight. You can test the stator coils in the generator by disconnecting the block connector with the three white wires coming from the engine and checking the resistances across the wires i.e three tests they should be within 0.44 - 0.66 ohms . If this checks out the manual then just says replace rectifier /regulator .Tony.

thanks for that, i will check what the coils are reading,

thanks kevin

Usually if you get a faulty rectifier / regulator you will get a lot lower voltage then you have so i would check the connections and make sure they are clean and tight. You can test the stator coils in the generator by disconnecting the block connector with the three white wires coming from the engine and checking the resistances across the wires i.e three tests they should be within 0.44 - 0.66 ohms . If this checks out the manual then just says replace rectifier /regulator .Tony.

hi sorry to jack the thread but i'm having the exact same problems as cranny, just done this test and my readings are anywhere between 0.13 and 0.40, does this mean the generator is knackered??

cheers