Charging voltage to high, cooking batteries and head lights

SOURCE: Yamaha FZR 600 not charging correctly with the lights on

I HAD THE SAME ISSUE. CHECK YOUR VOLTAGE OFF O THE MAGNETO, IT SHOULD BE IN THE 25V RANGE. IF THAT CHECKS OUT OK CK THE VOLTAGE IMEDIATLY AFTER THE VOLTAGE REGULATOR, I BET IT IS BELOW 14V. THE FZR IS PRONE TO HAVING THE REGULATOR GO BAD (THE OLDER ONES HAVE NO COOLING FINS AND THEY BURN THEMSELVES UP). THE BEST ONE TO BUY IS THE NEWER VERSION FROM A 1999 FZR, IT HAS COOLING FINS WHICH GREATLY PROLONGS THE LIFE. YOU HAVE TO DO SOME SLIGHT WIRING MODS, BUT NOTHING ANYONE COULDN'T DO. SEARCH FOR FZR REGULATOR UPGRADE AND IT WILL EXPLAIN EVERYTHING! I HOPE THIS HELPS! GOOD LUCK!

SOURCE: Bike won't start, battery bulged

Chances are it is the rectifier/regulator which is a sealed unit that has to be replaced if faulty. A bad one can cook your battery as well as your light bulbs and wiring. To check this connect a VOM across your battery terminals while the bike is running. If normal you should see about 13.5 volts. If your voltage climbs up to the 18 to 22 volt range or higher you must replace the part before you do further damage. Also be aware of the dangers of over charging a battery as it can explode and cause personal injury. If your battery has been cooked you will have smelled sulfuric acid and the battery will become hot to the touch. If that is the case you will also have to replace the battery as well as it will no longer hold a charge. When this happens the battery will bulge and this is called plate bow. By replacing both the battery and the rectifier/regulator you should be as good as new. In very rare instances it could be the stator which could cost a lot more but chances are its just the rectifier/regulator. I've seen them for very cheap prices on Ebay.

SOURCE: battery not charging

battery is loss

SOURCE: Battery not being charged

voltage regulator may not be charging...gain access to battery and take reading with key off ..should read 12.6v or better...then turn on key and see if lights put on a load and voltage drops..then start engine and crank to 300rpm and with votmeter you should see it raise uo quickly to about 13.5 or 14v and immediate drop back down to about 13v ,,,if you got a decent battery,,,this will prove that the regulating system works. if not your stator is bad...find the connector to the stator and check any two wires leading to the stator for .1to1ohm this is a good reading, if not stator is bad. you said you had 4v is that correct? because if it is, your battery is shot and needs replacement.

SOURCE: charging system is overcharging the

rectifier (voltage regulator) is responsable for stady 14V suply.
It should be him. Check battery when not conected?!
But I realy think it's rectifier cousing problem!