[Patbishop2004]

The K1300s died on me last night 150 miles into a journey. Managed to get it recovered and it jump started from a car so looks like the battery had run down, pointing to an alternator issue. Replaced with a new battery and the bike fired up fine and got me home.

On the way back the battery warning light was red the whole way.

We checked the battery with a voltmeter at home and there’s no change in voltage when starting or revving the bike so looked like the alternator is faulty (or a connection). So took the tank off to see if anything was obviously loose or any frayed cables etc.

Found that the connector with the 1 blue wire going to the underside of the alternator was not connected. Not sure if it was disconnected before or if it got disconnected while taking the bike apart to check the connections.

So connected that back in and put everything back together.

Took it for a run and I am still getting a constant battery red warning light. Suggesting that the alternator is still not charging the battery.

Before I go into replacing the alternator. Should the voltage be visibly changing on a voltmeter when firing and reviving the engine?

I am at my parents in Exeter and need to get back to London in 170 miles.

I now have 2 charged batteries. If the alternator is not charging the battery, does anyone know how far I am likely to get running just on the battery power?

If it was never charging, the previous battery got me 150 miles down here. But I don’t know if it had failed before the journey, or if it failed on the way. I had no battery warning light during the journey. The only warnings where when the power started shutting down (abs first, then speedo, then rev counter, then ignition).

On the subject of the battery warning light, after I installed the bmw supplementary wire kit for the hot start issue, I used to get a battery warning light at start up, but it would go away after a minute or two of riding.Now it doesn’t go away.

Could anything have been damaged if I was running the bike without the blue wire connected to the alternator?

Assuming the alternator is not faulty and it was due to a loose connection, could the system be panicking because it had run to failure which is throwing up warning lights as a result? E.g I am now getting a service message even though I had it serviced 3 months ago. This message was reset when serviced.

Need to decide today whether I risk the journey back to sort it at my house, or have to leave it here.

Appreciate any advice!

Thank you

 

[EricK1300GTSE]

I reckon if the alternator had not charged the battery then you've run the battery down very low, possibly below recovery point. With ignition off, and a multimeter connected, you should see a voltage drop when you turn the key, and a further voltage drop when you start the engine. If voltage drops below 10V when engine starts, battery is too far gone.



Same if running and alternator charging correctly you should be seeing 14.3-14.5v going into the battery. If not, then alternator, or more precisely the diodes in the alternator are shot. Diodes can be replaced, but if original alternator, there's a chance that windings may also be damaged, hence a new alternator may be required..

 

[cstumpf750]

If you do decide to make the run, pull as many fuses as you can To reduce the load. I’ve never done 170 miles though, I have done about 100. But it was on a 97 Honda VFR750 and the regulator popped. Luckily I had added a volt meter. So I noticed the lack of charging quickly. I pulled over and pulled all the fuses I could. I only had tachometer, no lights or instruments. But it was daytime, so I used hand signals. But that bike was carburated so the battery only had to run the CDI box. Our bikes are full injected and have ECU and canbus, so I suspect you won’t make it even with fuses pulled to eliminate lights.

 

[mrdryclutch]

If you do decide to make the run, pull as many fuses as you can To reduce the load. I’ve never done 170 miles though, I have done about 100. But it was on a 97 Honda VFR750 and the regulator popped. Luckily I had added a volt meter. So I noticed the lack of charging quickly. I pulled over and pulled all the fuses I could. I only had tachometer, no lights or instruments. But it was daytime, so I used hand signals. But that bike was carburated so the battery only had to run the CDI box. Our bikes are full injected and have ECU and canbus, so I suspect you won’t make it even with fuses pulled to eliminate lights.

Near as I can tell on my 2006 K1200s, and I think the 13 is similar. We do not have any fuses. Everything is run by the Canbus.

 

[QuelleCrise?]

If you do this have a friend follow. They can charge you battery a. Whilst you use b.
This allows you to not kill either battery which is unacceptably dangerous in traffic.
And if both die you have safety and support.

Did this once in a 97 DeVille. Battery was flat from intermittent alternator. Max I got was 10 mins per boost as there was no second battery in my scenario. Made it 50 miles to home. Complicated by night and headlights adding to load.

So if you do this foolhardy thing do it in daylight headlight bulbs removed.
Do it at dawn. To avoid traffic also Avoid expressways. Go light on the rpm and do not drive faster than need be.
Tuck to reduce frontal area and max your tire pressure.

Also do not boost your bike from a running car.

 

[Bradmiester]

The K1300s died on me last night 150 miles into a journey. Managed to get it recovered and it jump started from a car so looks like the battery had run down, pointing to an alternator issue. Replaced with a new battery and the bike fired up fine and got me home.

On the way back the battery warning light was red the whole way.

We checked the battery with a voltmeter at home and there’s no change in voltage when starting or revving the bike so looked like the alternator is faulty (or a connection). So took the tank off to see if anything was obviously loose or any frayed cables etc.

Found that the connector with the 1 blue wire going to the underside of the alternator was not connected. Not sure if it was disconnected before or if it got disconnected while taking the bike apart to check the connections.

So connected that back in and put everything back together.

Took it for a run and I am still getting a constant battery red warning light. Suggesting that the alternator is still not charging the battery.

Before I go into replacing the alternator. Should the voltage be visibly changing on a voltmeter when firing and reviving the engine?

I am at my parents in Exeter and need to get back to London in 170 miles.

I now have 2 charged batteries. If the alternator is not charging the battery, does anyone know how far I am likely to get running just on the battery power?

If it was never charging, the previous battery got me 150 miles down here. But I don’t know if it had failed before the journey, or if it failed on the way. I had no battery warning light during the journey. The only warnings where when the power started shutting down (abs first, then speedo, then rev counter, then ignition).

On the subject of the battery warning light, after I installed the bmw supplementary wire kit for the hot start issue, I used to get a battery warning light at start up, but it would go away after a minute or two of riding.Now it doesn’t go away.


Could anything have been damaged if I was running the bike without the blue wire connected to the alternator?

Assuming the alternator is not faulty and it was due to a loose connection, could the system be panicking because it had run to failure which is throwing up warning lights as a result? E.g I am now getting a service message even though I had it serviced 3 months ago. This message was reset when serviced.

Need to decide today whether I risk the journey back to sort it at my house, or have to leave it here.

Appreciate any advice!

Thank you

Pat Bishop,

No where in your diagnosis did I see the Voltage amount or measurement.

If there is no voltage showing, then you already know your battery is cooked and or defective. If you hook up your buddies battery that is working you can easily deduce if your system sees the required voltage and allows it to be charged.

A voltmeter is an instrument used for measuring electric potential difference between two points in an electric circuit

If your Alternator is not generating a minimum of 12.7 to 13.5 volts, then your battery is cooked and your Can Bus will not be happy and may not allow your alternator to produce current.

You have a Battery warning light, You have now set a hard fault in your ECU. So Red Battery Icon and Yellow Triangle for most people, screams: DONT RIDE ME UNTIL YOU FIX ME.

Everyone gets a battery warning light at start up! If its 2 seconds or under.....it's Normal. If it stays on longer and longer as in 3 secs, 4 secs, etc., etc, your battery or your alternator is on its way out.....

This is your responsibility as an owner/ operator to service your bike regularly. Did you install a minimum of 14.5 Amp hour AGM with at least the required cold cranking amps?


An alternator failing on a K1200 is rare, much less a K1300 unless you or the previous owner(s) repeatedly jump started this bike and over amped your circuitry.

Happy Hunting

 

[WPV]

Some alternators require exciter voltage to generate power. With this type of alternator a completely dead battery means that the alternator will not generate voltage. There are alternators that will "self excite" (a somewhat obscene concept) and require no battery voltage. I do not know which is in a BMW.

 

[EricK1300GTSE]

I don't think that these bikes have "smart" alternators I.e. the ones that regulate how much voltage they put out in reaction to the system load.

 

[QuelleCrise?]

OP has not replied. Alas.

 

[Duncan Hare]

Hi Patbishop2004

As others have said, the voltage should settle at 14.3 or so once the bike is running.
I had this on my K1300GT once after I'd had some TIG welding done on the frame and the firm who did it forgot to plug the alternator back in. I got only a few miles down the road - these bikes draw a lot of current and the alternator puts out a lot (55A on the S/R and 70 on the GT) so if the alternator's down you don't get far (unlike the old days -1960s Triumphs had 10A alternators) when we could "milk" a bike for miles just on the battery.

I have a spare alternator for a K1300S - almost as new condition if you need one.

I also live in near Stroud, so not far up the M5 if you happen to still be in Exeter.

 

[Duncan Hare]

I don't think that these bikes have "smart" alternators I.e. the ones that regulate how much voltage they put out in reaction to the system load.

They're wound field alternators (car style ) so are indeed "smart" and only draw the current the bike needs (rather than having a fixed magnet alternator and drawing the current it produces, all the time and dumping the surplus to earth in the regulator like most other bike set ups).

 

[Patbishop2004]

Thanks for your input everyone.

I decided not to risk it and took the train home. Took the alternator with me and dropped it in to an auto electrician to see if they could work out what was wrong. Turned out the alternator shaft had broken! So I ordered a low ish mileage 2nd hand alternator on eBay, replaced the cush rubbers and fitted that. Everything now working as it should.

Seems pretty rare to have the alternator shaft break? Replaced the cush rubbers (which were broken apart) as a precaution in case it was linked to the old loose rubbers. But would have though an alternator breaking so drastically on a 27k miles bikewas pretty rare and unlucky. Anyway, with the replacement all installed correctly and with new rubbers, hopefully this is the last I’ll hear from the alternator.

 

[Duncan Hare]

Glad you got it sorted