Battery drain R80G/S

[oldenoughtoknowbetter]

On the last stages of completing a complete restoration of a 1981 G/S. New Odyssey battery fitted which drains down to round 11 volts after two or three days. Have fitted a voltmeter between the earth terminal on the battery and the earth strap, which confirms a parasitic power loss. Obviously, I've disconnected the time clock therefore there should be no drain at all on the battery with the cables attached and the ignition switch turned off.

When I do connect the positive then negative leads to the battery there's a tiny clicking sound which I've traced to the headlight relay. This is a new loom from Motobins, which has a port for a headlight relay whereas the loom I removed didn't. Clymer shows the headlight relay as being appropriate to USA models only. So of course with the new loom the headlight works fine with a headlight relay and doesn't work without one. But if I remove the relay from the bike the parasitic power drain is cured. But then I have no headlight of course.

During the restoration I replaced the handlebar switches and these of course connect to the red and black blocks on the loom. I've removed the new connectors and replaced the switch/connector block assembly with the one I took off and the power drain is still apparent. Therefore the problem is not with the new switches.

Everything points to the relay (I think!). The one I used, also from 'Bins, is a five spade Fiamm 30A relay. I don't have another on any of my other bikes so can't simply swap over to try. But is this likely to be a problem with the (new) relay or might the problem be elsewhere?

Scratching my head a bit with this one. Any suggestions appreciated!

 

[Dellis]

A relay is only a couple of quid so that would be where I'd start.

Dave

 

[oldenoughtoknowbetter]

Relay

Thanks Dave,
The relay which Motorworks sell for the G/S is completely different to the one from 'Bins. The one I have has 5 connectors but the one from 'Works only three! But there are five wires to the relay dock on the loom. Have had a look on the fiche for the part number but the UK version didn't have a relay! Couldn't find one on the USA listings either! Confused.
Dave.

 

[solidstate100]

In the deep depths of my mind there is a foggy memory of something similar with mine. I have a G/S and its a USA model. From memory, the USA headlight is supposed to switch on with the ignition (like all bikes do now) but there was a mod were you switched one of the feeds to the relay on the back of the igniion switch to a different terminal and then had "standard" headlight action, which mine has.

Are you sure the ignition switch is wired correctly? Does operating the kill switch influence it?

 

[MickDB1]

If you have a multimeter with a Amps settings - uncouple the positive and insert the meter - it may give you the reading of how many amps draw that should/could give you a clue as to what is using the juice . I think HTHY and good luck

 

[oldenoughtoknowbetter]

Absolutely everything works as it should except for the battery drain. But yes, I can check the amps. Thanks. This afternoon I compared the number and configuration of spade connectors on the relay with female connectors in the dock. Hard to see but one of the spades slots into an "empty" hole in the connector block so presumably it's not the correct relay for this loom! Motobins listings says it is but the one shown by M/works seems to have the same configuration of connectors as the block. So obviously I've ordered one from 'works and I'll see how I get on. If this doesn't do the trick it's back to the ammeter!
Thanks again.

 

[oldenoughtoknowbetter]

Problem solved!

The replacement works just fine. Therefore incorrect relay listed for this bike. I'll mention it to the supplier.
Thanks everyone for your input,
Dave.