Help - flat battery / bike won't start!

Hi,

Due to underuse for which i am profoundly ashamed of, my Honda CB500s
(which was always a crap starter) flattened the battery trying to start
the bike today after several weeks of not using the bike.

I am such a newbie that I have no idea what the best way of getting
going again is.

Before going flat, I suppose the battery turned over OK for a total of
around a minute or maybe a bit more, but the engine didn't fire once.
Does this mean the battery was probably on its last legs anyway?

All constructive suggestions gratefully received.

(I do not live on a hill!)

Thanks,

Pete

 

Peter Boulton says...

Check the kill switch once the battery is charged again.

 

Lozzo wrote on 10/10/2004 19:03:

Be gentle with me here, but will the kill switch stop the battery
discharging while the bike is not used?

Thanks,

Pete

 

Andy Bonwick wrote on 10/10/2004 18:52:

Right, thanks! So I can safely jump start from a car? That's better
than charging the battery using a charger?

I also have a Halfords charger - it is an 8amp "for all standard,
maintenance free and sealed for life 12 v automotive lead-acid
batteries." I used it once a long time ago on a car battery.

Will this charger be OK for a bike? The Honda owners manual says it's
an 8amp 12v battery so the amps and volts seem to be correct.

I am very unconfident about this stuff, but I guess the charger must be
just right?

Be gentle with me - the manual is full of warnings about explosive
gasses etc. so I am a little timid!

Thanks,

Pete

 

No, but it'll stop the engine from starting, get it now?

 

Peter Boulton says...

No, having the killswitch in either position won't make the blindest bit
of difference when the ignition is turned off. On most Hondas you can
still turn the engine over on the starter button when the killswitch is
in the off position, and it aint going to fire when it's like that. The
symptoms you described made it sound like the killswitch is off, rather
than on. I

I think you flattened the battery trying to start an engine that won't.

 

muddycat wrote on 10/10/2004 20:11:

You only make that mistake once, and I made it a while back.

Basically from new the bike was a poor starter in my opinion. It was my
first bike, so I don't know what's normal, but it only started reliably
of I used iot every day. Otherwise it was a patient procedure, though
today is the first time it refused.

 

Andy Bonwick expressed precisely :
8amps is its maximum output into a flat battery. 8amps into a bike
battery would cause it to overheat and possibly explode, or at the very
least damage the plates.

Your battery is an 8 amp hour one (AH). 8AH denotes the power that
battery can deliver over a period of time. Roughly this will be...
8amps for 1 hour, 4amps for 2 hours, 1amp for 8 hours, 0.5amps for 16
hours.

Agreed!

I would suggest a controlled charger of no more than 0.5amps output.
Controlled as in that it stops charging as soon as the battery attains
a fully charged condition.

 

Right then.

Choke full on, twist the throttle once, hit the starter. Works for most
Jap Bikes. If it has set for a long time, dump the petrol and refill the
tank. You might want to check the plugs too.

 

You can - it'll get you going.

That'll do to get you going.

It'll be alright as long as you don't leave it connected all night
long. It will only charge at 8 Amps into a dead flat battery - on
yours it will probably start at about 2 or 3 Amps and drop quickly to
about 1 Amp charge rate.

Just use the charger for 1/2 an hour to an hour - should be plenty
there then to start the bike. Unplug the charger from the mains before
connecting it or diconnecting it from the bike battery and it would be
best to remove the -ve (earth) lead from the bike battery before
charging and reconnect it after you have finished.

 

the cont known as ZR7-S says...

James, you know what attributions are? Please use them.

A working sig sep would be nice too.

 

Buy a new bike.

 

muddycat pretended :

Twisting the throttle (or pressing the accelerator sharply) only works
where the carb is fitted with a pump, as used to enrich the mixture on
hard acceleration. On some older cars with an automatic choke, you
pressed the throttle to set the choke.

Pointless to do this on injection vehicles and/or most if not all
bikes.

 

Seems to be the only way my SV will start.

 

Must be something wrong with it then, surely. All my bikes fire up
without twisting the throttle. Infact, I don't remember having a car or
bike that needed the throttle to be blipped when starting.

 

Same here, my T595 is injected, and starting it is strictly no throttle
and it fires instantly, anything else and it will not start.

Starting the Rotax is a different matter completely, full choke, part
throttle and if it has not started by the 4th kick then go to no choke
full throttle and expect pain.

 

heh

Or it could be I'm just wrong. I just started it choke full on no blip.
Fired right up after sitting 2 days. Hmm, I'll change my ways and see
what it does on a really cold day.

 

Erm, no it doesn't. Close to utter bollocks, in fact.

 

Heh.. That's more than the first time I've heard Rotax and pain the the
same paragraph.