Electrical problems - overcharging?

Hi All,

It's that time of year when everyone starts posting "my bike won't start" messages. So here's another one (I have looked through the site, but I couldn't find one quite the same as this).

My bike won't start, or at least, it's reluctant to. When I press the starter, it's just about capable of turning the engine over, and if I'm lucky it'll catch & run.

With everything turned off, the battery reads just over 12 volts.
With the engine idling, the battery reads 14 volts.
With the engine at 5000 rpm, the battery reads 18 volts.

The battery is about four years old, so I'm aware that it may be past its best. However, does the 18 volts signify that the battery is going high resistance, just due to age, or does it mean that the Reg/Rect is bad, or some combination of the two, or something else?

Thanks for your help.

[Biker Biggles]

Reg rec is duff,hence battery overcharging,and battery will probably also be duff now due to overcharging.Does the battery get warm after a longish run?Any nasty smells coming from it?All signs that it is "cooked"

The voltage shouldnt exceed 14.5 volts at 5000 rpm; 18 V is therefore too high! You'll need a new voltage regulator / rectifer. If you can, find someone to test the efficiency of the battery, this will let you know if its gone duff (i.e. not efficiently holding a charge or not efficiently being charged). I suspect though, from what you describe, it is bust. I think there is a guy on here called batteryman who will be able to advise you on the best battery for your bike - it is not always best to buy a cheapie from halfords, because they can just go bad after a relativly short while too!

If you have your bike layed up unused for long periods (few weeks / months) then keep the battery connected to a trickle charger, such as an optimate, to keep it in top condition

Matt

[the_lone_wolf]

The battery is at risk of splitting and leaking if it's overcharged, get it out of the bike pretty sharpish I would...

oh dear I seem to have the same problem here
first thing in the morning it hardly moves the motor ... just like a very flat battery

engine switched off battery (YT12ABS) checked at operating temperature 13.6v ( battery just over a year old)
at 1100rpm 16.4v
at 1100rpm full load 14.7v
at 2000rpm 18.6v yikes

ebay any good for a reg/rec - any help appreciated peeps

w reg naked
17k miles
been cherished by previous owner
abused by me... (

I have same issue, new battery and rectifier time. Run a searh for title 'chat' You will come across 'regulator chat thread'

[andrewsmith]

it may be best if your doing a lot of work to replace the battery with a gel unit as i'm wishing i'd done it when a did mine.
Lead acid batteries probably GS sealed units for 50 notes new.

I got the local bike shop to order me one of these:
http://www.electrexworld.co.uk/rr85-...er-3206-0.html
(I think, check the part numbers before you order). It's not manufactured by Suzuki. It comes with a longer alternator cable, so that you don't use the one in the wiring loom. It's a deal chunkier than the original unit, so I'm hoping that it'll last longer.

Hi
before I splash out on a new rec/reg (70 sobs)
can anyone explain why this would cause the engine to crank very very slowly?
there is loads of life in the battery which is just over a year old

after the engine has warmed up the engine spins freely..

TIA

Originally Posted by stepheng

Hi
before I splash out on a new rec/reg (70 sobs)
can anyone explain why this would cause the engine to crank very very slowly?
there is loads of life in the battery which is just over a year old

after the engine has warmed up the engine spins freely..

TIA

Because it b*ggers the battery up.

Wikipedia:
When a battery is recharged at an excessive rate, an explosive gas mixture of hydrogen and oxygen may be produced faster than it can escape from within the walls of the battery, leading to pressure build-up and the possibility of the battery case bursting. In extreme cases, the battery acid may spray violently from the casing of the battery and cause injury. Overcharging—that is, attempting to charge a battery beyond its electrical capacity—can also lead to a battery explosion, leakage, or irreversible damage to the battery. It may also cause damage to the charger or device in which the overcharged battery is later used. Additionally, disposing of a battery in fire may cause an explosion as steam builds up within the sealed case of the battery.[69]

In short, it's cooked!

The engine and other odds and sods will go, because they are getting more than enough power, although 18v might do your light bulbs as well.

IIRC, the reg/rec from a CBR600 (2006 on) is apparently the one to go for.