Dead battery

[Giddsy]

Morning all,

So I have an intermittent battery problem.

Itt is a relatively new battery so should not be a problem. About two weeks ago I went to bike haven't not ridden it for about 3 days and battery was dead. Strange I thought but hey ho, charged it up and it was fine. Checked with a multimeter and was holding it's charge without a problem. Have since ridden it pretty much everyday and it's been fine. Go to start this morning having parked up about 5pm yesterday and nothing.

I am thinking it may be a short somewhere. What do you think and how do I go about sorting it? Not much experience with electrics. May also suspect the dataool alarm but that wouldn't be intermittent if it was the cause I shouldn't have thought.

Thanks for your input.

James

[Pete.L]

Hate to say this but the Alarms or their wiring are always a favorite.
Only way to tell is to put your meter on the amps setting and see how much current it's drawing. Alternatively you could pull the fuses one at a time and check which circuit the current is being drawn from.
Check all your wiring for breaks and plugs and sockets for corrosion too, sometime a good physical look is just as important.

Pete.l

[Giddsy]

Hi Pete,

Thanks for your reply.

So what are acceptable levels for current draw with what should just be the alarm taking a small amount of juice?

Will also have a good old look and try the fuses trick. I suspect I might be pulling out the alarm come Saturday tho...

Thanks,

James

[Pete.L]

According to this system 3 Datatool it should be 2milli amps
http://www.datatool.co.uk/consumer/prod ... ct=system3
You will have to try looking up the current draw for your model. Pulling the fuse for a while is another good idea.
The rest of the system shouldn't draw any current you can read with your meter or at least be in the micro amp range.

Pete.l

[Giddsy]

Thanks Pete,

Will look into to it tonight / this weekend and let you know how I get on.

James

[Dazjm]

Remember ur meter has to be in circuit to measure current, not across the + and - terminals like if you were measuring Volts.

[Giddsy]

Right, just checked the charge with the engine running and it is highly erratic, going anywehere between about 8 and 13.5v. I'm going to check connections and clean it all up. Any other suggestions?

Thanks,

James

[tony.mon]

Reg rec.
Output to battery should be in the 14-5- 14.8 range or close to it when charging a discharged battery, and around 12.5 or thereabouts once the battery's up to full charge.

8 volts is just wrong.

[Giddsy]

Hi Tony,

Already changed r/r to an r6 one, guess that may have gone tho... and it's not going over 13v and I was under impression an r/r on way out over charges...

[tony.mon]

I have a spare R6 reg/rec in stock (thanks to Jonesy) if you want to try swapping it over?

And it can be a loose/dirty connection to the R/R, so might be worth a clean-up and check connections.

[benny hedges]

Hi Tony,

Already changed r/r to an r6 one, guess that may have gone tho... and it's not going over 13v and I was under impression an r/r on way out over charges...

if the regulator has gone it could charge higher - if the rectifier has failed it might only charge 1/2 the voltage, if that
thing is, its all one unit so if its got a fault its fkt - unless its a faulty genny coil or loose wire in the connector

[tony.mon]

- if the rectifier has failed it might only charge 1/2 the voltage, if that

Might be worse than that.

Remember the voltage that comes out of each of the coil sets (there are three) produces a fluctuating wave of positive and negative voltage, roughly from -35 V to + 35 Volts.
The purpose of the rectifier bit is to only let through positive bits of electricity, (then the regulator part caps it at 14.8V or thereabouts).

Now, if the rectifier bit fails, while one third of the generator windings is trying to push in +25v, another third of the windings is trying to push in -20-odd volts (at a guess), because the phases overlap.

So the potential difference between the two at the battery is in this case only +5 volts in this example.

I'm sure someone will put in a good diagram which shows phase overlap.

This might explain your readings, but still sounds to me like a buggered R/R, if no obvious loose connections.

[Giddsy]

Thanks again guys and Tony for offer of r/r.

Found the problem, one of the wires going into the r/r had all but burnt through. Dodgy soldering by me. So need to re-do them all.

So the next question...

The soldering iron I have is too mickey mouse to heat up the wires sufficiently to get the solder in. It is a 25w iron.

What is the best tool for the job? Halfrauds have a gas soldering iron for 14 quid or a 40w same price. Could I expect these to do a better job and which one would you recommend?

Cheers

[benny hedges]

Dodgy soldering by me. So need to re-do them all.
What is the best tool for the job? Halfrauds have a gas soldering iron for 14 quid or a 40w same price. Could I expect these to do a better job and which one would you recommend?

those little lighter gas soldering irons are bloody brilliant.
ive got a maplins one - cost me a tenner years ago with a few spare tips.
it will definately do the job and very portable.
a lot of my work is on panels up in the sky / underground etc and so i find the gas iron very versatile.
if theres a fire risk just turn off the gas and it will stay hot enough to do the job.
keep the tips clean tho cos they burn through quite quick with resin cored solder ;)

tin the wire and the connector separately and you will only have to touch them with the iron and they will stick proper.
you've probably done the old trick of using the iron to carry melted solder rather than just using it to apply heat

Cheers

[tony.mon]

If you took the job indoors it's easier, the breeze cools a low wattage iron as fast as it heats the job.
However, as some electrical components are damaged by heat, the quicker you solder a joint the better, so a higher wattage one is what I use, with a variable heat output.
Maplins jobbie does it for me, although to be fair I've never tried a gas one.