sup guys, my 92 cbr 600 hadn't been used for 3 weeks and battery went dead, i charged it for a bit then took the bike out for a 30 mile run (headlight on) stopped for 5 mins and when i hit the start switch it just went TICK! totally dead. Recovery guy came out, charged it for 10 mins and of i went! (lights off) now it starts fine again. also battery reads 13.5 running, put lights on and it goes down to 12.3 but goes up when revved as it should but lights don't get brighter when i rev it. this has now happened a couple of times and its a new battery. any ideas?

 

load test the battery...because its new dont mean its not bad...under load volts should not go below 12.00 ...

 

It's possible the battery is not properly holding a charge, and the way to check that, is like squale said, get it "load tested".

Also, you should do the general electrical testing from the manual, for the battery and the charging system: a leak test, to see if there is a short, and the battery is draining excessively while just sitting there, test the charging system for appropriate amperage/voltage, so you know the stator is actually pumping juice to the battery, and lastly, test the R/R.

All of these tests are somewhat simple, though it can be a pain removing items from the bike to get to what you need to get to!

Hopefully you've just got a battery that's not holding a charge, and not a good battery, but with a short somewhere (that's where the leak test will come in handy), cuz tracking down a short can be a booger!

Good luck!

 

cheers guys, cleaned up the connectors, checked wiring (found some broken earths) literally broken wires at the connectors, tested battery under load today and came down to 12.83 but no lower,replaced the rectifier anyway (£18) and bought a trickle charger so i don't get caught out again! :-) off out now cause it's sunny again in Scotland! vvrroooommm!

 

Nice! Hopefully that sorted things out!

 

good deal...