come on baby......dont do this to me now

[masterofpuppets]

well ive been getting a bit of an intermittent starting problem the last couple of days.... ever since i changed my oil actually... but most probably a coincidense. well the bike sometimes starts sweet.....first pop and vroom. but sometimes she will turn over heaps and just not catch on. and today i got on to go to work and the battery was pretty much dead.. turned over twice then died. when i crash start it it goes fine.
my guess is the battery might not be holding charge, or there is an intermittent short somewhere that is draining it out. so ive been hitting the kill switch to off and turning off the lights when not running, but still wont go sometimes.
i measured the voltage on the battery and it was at about 12.5 but i didnt measure how many amps it was running.
what are your people's suggestions???

[Sniper]

Battery.........

[Potzman]

yeah man your battery might be past its used by date, although voltage seems about right if that voltage is when the bike is off.

could also be the alternator not charging battery, voltage should be higer across battery when the bike is running.

[masterofpuppets]

yeah the voltage was higher when i measured it running. the thing is i thought bikes, like cars would have a voltage restrictor from the alternator to the battery. when off accross the battery it reads 12.5, when idling it s about 13.5, at 10krpm its about 18ish volts. is that normal or not.

[WildBoarMouse]

Hey mate... yep, when fully charged a lead acid battery should generally sit at around 13.4 - 13.6V without any load on it. If you have a trickle charger, stick it on overnight and measure it the following day. It should definitely be above 13V. The charge voltage sounds about right... measuring the available current isn't all that easy. A service centre should be able to connect it up and measure the CCA (cold cranking amps) for you. For cars it usually measures in the hundreds of Amps... not sure how many for a bike... probably enough to pop your multimeter though

[masterofpuppets]

well i guess im off for a new battery tomorrow then. ive had to top this one up more than a couple of times and i must admit i havent always used distilled water. so off for a new one tomorrow. i know the zxr250c uses a dry cell maintainance free thing but its got different dimensions and wont fit in the compartment. that would have been sweet.

[metric]

had a similar problem with my bike... a new battery sorted it out...

[**R1**]

It shouldn't read 18volts at 10,000rpm, it should regulate around the 13.5v mark...id be checking the regulator, over charging the batt will kill it soon enough....

[masterofpuppets]

yeah thats what i thought but then i thought maybe they dont have a regulator. i mean why do bikes have a drain hose and need topping up often. so i thought maybe unlike a car they dont have a regulator and the battery just boils out quite often. maybe i'll just ask at the shop tomorrow

[WildBoarMouse]

If you get the chance, maybe swap in a good battery, turn it over and see if it makes a difference, and purchase the battery based upon that observation?

[masterofpuppets]

yeah but the thing is sometimes even with this battery i got in it it will sometimes just start the first pop. whats the possibility there is an intermittent short somewhere that drains the battery now and again???

[WildBoarMouse]

Hmm... maybe disconnect the battery each night for a week (or until you'd have expected the fault to show itself) and then reconnect it in the morning. If you no longer have the problem then something funny is (was) happening overnight with the electrics.

I was under the impression that with bikes the battery is completely disconnected from the system when turning the bike off (unlike a car which powers stereo clock & alarm etc...) am I right in thinking that?

[imdying]

at 10krpm its about 18ish volts. is that normal or not.

Sounds like your problem right there. Know anyone with a regulator you can borrow? Find out the test procedures for your one.

[MSTRS:Me]

Sounds like your problem right there. Know anyone with a regulator you can borrow? Find out the test procedures for your one.

Probably. And putting 18v into a battery designed for 12-14v will boil it off real quick, hence frequent top-ups reqd. New battery & new regulator coming up.

[buellbabe]

Had a similar prob, battery not holding a charge. It would charge up fine and the readings were correct but the next day, flat again. Replaced the stator and that made no difference. Had them all scatching their heads at the shop. Finally found the cause, a short in the headlight.
Sounds like its yr battery, you didn't mention how old it is?
But if its a short they can be bitches to find...
Good luck.