R80 electrical problem
 

Hello my friends,

I'm currently in northern Peru labouring my weary brain cell with an electrical issue relating to my R80. It's running but the electric start sometimes thinks twice before working. Also, today the engine cut out while on the move. Because it didn't bump-start while coasting, my best guess is that there's a short circuit relating to the engine kill-switch.

I've found no chafed wiring around the steering column and the bundle of earth wires under the tank are fine. And so I have resigned myself to a full investigation with the dreaded multimeter. Before I do, I was wondering if any you wise wanderers knew of common gremlins (e.g. starter relays, the starter/kill switch . . .)

Thank you!

Bob

I have come across one traveller who had no alternator charging - starter motor stopped due to low voltage .. later the engine stopped due to low voltage ...
So basic question .. when you first turn on the ignition .. do you have TWO red lights? One is for the oil pressure - the other for the alternator/battery. If the alternator/battery one is not working you may not have alternator charging the battery.
If the battery voltage measured with your multimeter is low (less than 12.5 volts) then .. charge it ... then check for sparks, charging ...

Engine kill switch will turn off the instrument warning lights (as well as the ignition) .. if they came on when the engine stopped .. it aint the switch.

Thanks for the reply Warin. Both red lights light up, the battery one going out with acceleration so battery is charging. Also, if the ignition doesn't work with first press, the second comes full power. Still, I'll check the voltage tomorrow. But I think it's something else.

The engine has also 'coughed' occasionally over the past few rides, where the engine cuts out for a lurching moment, again while on the move. I thought it was rough fuel, but now believe it's the same electrical issue.

Cheers,
Bob

From your description it sounds to me like one of two things. 1. Start with basics, check battery terminals are clean and tight. Also check the battery - lead is tight at the connection on the gearbox. The + lead goes to the starter solenoid so that is harder to check and I have rarely seen these come loose. If you do check it make sure you disconnect the - lead first to prevent shorts with your spanner on the engine casing. 2. If the kill switch is electrically dirty this could also cause the symptoms you are getting. Sometimes vigorous operation of the switch back and forth for a minute may restore the internal connection. Failing that you could find the connector block coming from the switch inside the headlamp, disconnect it and bridge the wires on the block going into the loom to restore the circuit. If you do this you will loose the kill switch function, since you have effectively taken it out of the circuit. Check those and see how you get on. If you are still stuck I'll try to help. Good luck, Guy.

Bob, if you require further assistance it would be useful to know the year of manufacture.

Check the earth. -ve battery post to frame, swingarm, forks etc. No resistance.

Andy

Also check the condition of the alternator brushes and the condition of the slip rings on the rotor. If the brushes are about 60-70% worn which means they are disappearing inside the plastic casing they need replacing, if the slip rings are dirty they can be cleaned with scotchbrite.

Suspects so far;

The alternator - as the light is working correctly I'd think that is ok.

The kill switch will make itself evident by the instrument warning lights not working.

Possible loose wire from battery to starter motor (and return to the battery negative terminal).

All possibilities, needing carefull thought by the op to think about the symptoms and getting them to match the results of the above problems. More testing and information may aid analysis.

Electrics
 

Guy, Andy, Warin - thank you!

I'll take a closer look today. 1st coffee.

The year of the R80 g/s is 1981.

Anon,

Bob

Update
 

Gents,

An update. The charging system seems fine - battery reading 12.55 and 13.8 with revs.

Connection to and from starter motor also seems fine. Same goes for HT leads to coil.

Took off mudguard to inspect the crush of wires leading into headlamp unit. Found one earth wire with exposed wiring. Not sure if that's the culprit but taped it up.

Inspected other wires for wear and tear but found none, nor corrosion.

Tomorrow I head off in the direction of Chachapoyas, the ride between Celendin (my current location) and Leymebamba said to be heaven on Earth. Insh'allah I'll make it - Chachpoyas, not heaven.

To be continued . . .

Bob

While the fault is not evident it will be very hard to find

When it does occur you need to be very observant as to what happens.

If the engine dies do the instrument warning lights come on?
If not then possibly the kill switch, fuse holder, ignition key switch..
If it does than possibly the hall effect switch, coil, ICU ...

As for the starter?
You say it 'thinks twice before starting" ... you mean
you press the button and nothing happens .. then eventually the starter motor turns on? That just sounds like a dirty starter button.. or a relay contact.
OR
the starter motor turns and turns .. and eventually the engine fires up?

Hi Warin,

Thanks for the reminder to pay attention to the warning lights if the engine cuts out again.

As for the starter, the symptoms are like a dirty starter button which I've now cleaned (the starter motor fires up well on second push). I've been assuming the engine cut out is related but perhaps it's a separate issue.

Thanks again. More anon.

Bob

Sparks
 

Have any of you brilliants people experienced spark plugs which behave themselves perfectly except for one grumpy moment each day?

I've arrived in Vilcabamba, southern Ecuador after three days ride since the last post. On the second day the engine cut out again. This time I noticed the warning lights come on, so the problem doesn't seem to be the kill switch.

I was over-taking at the time. Of the 5 or so other times its spluttered or cut out, at least three were when I was accelerating relatively hard (over-taking or going uphill while the engine was still warming up). The 2 times it cut out completely, it started on the 2nd or 3rd attempt and behaved fine for the rest of the day.

According to my limited mechanical logic, when we accelerate we do two main things - open up the carbs + demand more from the coil and sparks. I don't think it's fuel related - I've checked the jets and cleaned the carb bowls and thin pipe. It feels electric.

I checked the sparks. One side looked less blue / more orange than the other. I changed them and had no problem yesterday riding. Sometimes I run them for 10,000 miles rather than the recommended change every 5,000. The last set had been going for c. 7,500.

I pretty sure the HT leads are fine. Not sure about the coil. I don't yet know how to check it.

I'm not yet convinced it's as simple as the sparks. The good news is that I've just read on this fine website of a great mechanic in Quito called Carlos, who knows foreign bikes and rides an R80 ST himself. Sounds too good to be true! Hopefully he's still about. It's only a few days ride there.

Any ideas, I would love to hear them.

Cheers,

Bob

With an intermittent fault like this possibly on the electrical circuit its difficult to test and catch the failing part 'in the act', sometimes the easiest way while you are on a trip is to replace each separate part in turn, keep riding and see if the problem is cured. Starting with the cheapest first - which you have just done with the plugs, next leads, then ignition/coil, regulator etc.
Before you start to go down that route I would 100% make sure that the other two parts of the triangle - fuel and air are perfect, make sure that the carb is working perfectly and remove and clean your air filter (if you have not already) and as a long shot make sure you do not have any water in the fuel tank - I filled up in San Pedro de Atacama and got a few big blobs of water in the tank from the gas pump, which gave intermittent symptoms similar to yours - under acceleration the water blobs would move back from the front (lower part) of the tank to the petcocks and make the DR cut out, then when the bike stopped the water blobs would move away from the petcock and (stationary) the bike would run fine when I got it started again.


Good luck!

Cheers Grif.

The water droplets is an interesting idea. A week's worth of riding ago I did empty the plastic tank completely but found no dirt or evidence of water in the fuel. Still, it fits the symptoms. I'll see if fuel in Ecuador makes any difference to 90 octane in Peru.

Thanks for the of the advice re narrowing it down.

All the best,

Bob