Brutal Starting Issue- 1983 R80 GS

Hi folks,

I'm a Nor'easter and it's just starting to really get cold. My 1983 R80 GS is in the garage and I've been working on it slowly. Last week, after a particularly cold evening with no tender on it, I went to start it in the morning and it wouldn't turn over, the ignition just started to slow down until there was a clicking. I figured that the battery was bad, bought a new PC680, installed it and that solved the problem. Last night, I did the same thing, left the tender off, and went to start it this evening and same thing happened. The lights come on, the engine will start to turn, but it sounds like on the first, second and maybe third try, there's just not enough juice to get it to turn. After the fifth or sixth try, it starts running low and dying out and then, after a a few more tries, it just starts clicking. Obviously I'm draining the battery, but a few questions here:

1) How do I know if have a starter or alternator problem?
2) Is it possible I have a faulty battery? If so, how can I know?
3) Do I need to keep a tender on the bike every evening in the cold weather? I ride deep in to January and have never had this issue before.

Thanks.

I would charge battery ,disconnect battery from bike maybe ground wire if yours is easy to get to. then next day connect it and see if battery is low again. If not, then something is draining it while its sitting .thats when the fun begins trying to find what draining it while key is turned off.Check battery wires and other hot wires for signs of wear that might be touching ground.

Welcome to the forum!

Here's an article on starting troubles on Snowbum's site: http://bmwmotorcycletech.info/startingprobs.htm

1) The alternator really doesn't come into play when starting the bike. Connections to the starter could be corroded resulting in little transfer of current. Same thing could be said of your battery cables. Make sure that the negative attachment of the battery cable to the back of the transmission is tight...don't over tighten the bolt however. Not sure when the older Valeo starters were used, but it's possible if you have one of those, the inner field windings can come loose which drag and can lock up the armature.

2) You can try to jump the bike using a known good battery...usually just hook up the donor battery but don't have the donor vehicle running. You can remove the battery and take it to any reasonable auto parts store...they can load test the battery.

3) A tender can certainly help in most situations. If you've been able to start the bike in past years under similar conditions, then something has changed.

Thanks

Thanks for all the replies. A couple of things I tried:

1) Successfully jump started with car battery
2) Put the tender on last night and it started right up this morning
3) Took the tender off today when I left for work this morning, got home this evening, and battery was too low to turn starter
4) There is a leak in oil pressure switch (which might be causing a short?)
5) I took the tank off and observed that the starter relay is clicking and blinking green, but nothing happens after that (here's a video: https://ve.media.tumblr.com/tumblr_pl1lkwwvPJ1spe6y3.mp4).

I just replaced the battery last week. Could the battery be faulty? Could the starter relay be faulty?

The battery could be faulty. The best test is to disconnect it and charge it fully. Then let it sit a day and see if it has self discharged.

It could be some circuit in the bike causing battery drain. Disconnect the negative cable and insert an VOM on the amperage setting between the cable and the battery post. See what the amperage is with the bike just sitting key off. It should just be a miniscule number of milliamps.

Report back.

With engine running at 3K RPM or so, what is the voltage across the battery terminals? Should be well north of 13.5v.

Exactly what "tender" are you using? Is it approved for the PC-680?
http://www.odysseybattery.com/documents/ODYSSEY_approved_12V_chargers.pdf

Update

Thanks for the suggestions. I ordered a VOM. It will get here today and I'll update you when I run the tests you suggested.

I kept a tender on it last night and the only change is that the clicking is faster, which you can see here: https://ve.media.tumblr.com/tumblr_pl2drmz8fS1spe6y3.mp4

Tender

Interesting question about the tender which I never thought of. I'm using (but I don't see it on approved list): https://www.amazon.com/gp/product/B00068XCQU

Coincidentally, it's blinking red and green now (indicating that the battery is over 80% charged, but it's been on all night- so it should be fully charged.

Update

Quick update: I disconnected the negative cable and there were no amps when I connected the VOM.

I just took the battery off and it was at 10.94, so I'm charging it now and we'll what happens after it's fully charged.

That battery wants 6 amps minimum at 14.7V to keep it at full charge. I have 3 PC-680's.

Got it- thanks. Once I have the battery fully charged, if it's acting the same way (losing voltage over a few starts) I assume it's either:

1) Bad battery
2) Bad alternator
3) a short somewhere that is slowly draining the battery.

Are there any other options?

PAS said:

That battery wants 6 amps minimum at 14.7V to keep it at full charge. I have 3 PC-680's.

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armartel said:

Got it- thanks. Once I have the battery fully charged, if it's acting the same way (losing voltage over a few starts) I assume it's either:

1) Bad battery
2) Bad alternator
3) a short somewhere that is slowly draining the battery.

Are there any other options?

Click to expand...

You said you did not find amperage flow with the VOM set on current and between the battery post and ground cable. Thus, drain from a short is ruled out if you did the test correctly which I assume you did.

The alternator only comes into play if you ride the bike, or run the engine a protracted period and the battery gets weaker and weaker. This is easily tested with your VOM measuring DC volts with the engine running. Look for 1 to 1.5 volts higher with engine running than engine off.

Self discharge is measured with the battery disconnected and at decent intervals. A battery ought not show more than a slight DC voltage decrease over even a week once the 1st hour or two has passed since the charger was disconnected. Soi charge it. Let it sit an hour and test the voltage. Then test it again in 24 hours. You should not see much change. If you do the battery is junk.

Thanks. The battery dropped from 12.4v to 11.5v over night. Going to try to get a replacement for the new battery today and see if that does the trick.

Any thoughts on the tender information? Do I really need to buy an Odyssey 6amp? Will the bike bring it to full charge after a good ride?

PGlaves said:

You said you did not find amperage flow with the VOM set on current and between the battery post and ground cable. Thus, drain from a short is ruled out if you did the test correctly which I assume you did.

The alternator only comes into play if you ride the bike, or run the engine a protracted period and the battery gets weaker and weaker. This is easily tested with your VOM measuring DC volts with the engine running. Look for 1 to 1.5 volts higher with engine running than engine off.

Self discharge is measured with the battery disconnected and at decent intervals. A battery ought not show more than a slight DC voltage decrease over even a week once the 1st hour or two has passed since the charger was disconnected. Soi charge it. Let it sit an hour and test the voltage. Then test it again in 24 hours. You should not see much change. If you do the battery is junk.

Click to expand...

armartel said:

Thanks. The battery dropped from 12.4v to 11.5v over night. Going to try to get a replacement for the new battery today and see if that does the trick.

Any thoughts on the tender information? Do I really need to buy an Odyssey 6amp? Will the bike bring it to full charge after a good ride?

Click to expand...

My PC-680's show at least 12.84 when fully charged. Odyssey will replace it IF you have proven to charge it correctly and it fails. (Just my opinion)
http://www.odysseybattery.com/documents/US-ODY-OM.pdf

Thanks for letting me know that. I just took it back to the store and they replaced it. Hopefully the new battery will solve the problem. If not, on to the next hypothesis.

PAS said:

My PC-680's show at least 12.84 when fully charged. Odyssey will replace it IF you have proven to charge it correctly and it fails. (Just my opinion)
http://www.odysseybattery.com/documents/US-ODY-OM.pdf

Click to expand...

Issues with Odyssey batteries are pretty much always due to lack of understanding how and why they are different. Everything you need to know is on their website but no one seems to read all that information. It's quite a bit to read actually but this is quite the battery and not a typical AGM. It is a heavy duty MilSpec AGM battery with great capacity and a very long life if treated properly. And BMW bikes do not charge the Odyssey to the voltage they specify unless you modify your charging system.
Some notes:
- A battery tender is just that; a tender. NOT a charger. So if your battery is discharged a tender is not going to charge it properly and especially not an Odyssey battery. Their charge algorithm calls for a constant voltage charge with current limited to 7AMPS. As the battery voltage rises the current decreases until it reaches 14.7VDC which is a full charge. A battery tender cannot do this.
- In order to know if your battery was good or not, load testing it after a full charge with an approved Odyssey battery charger is the only realistic way to test it. You can get a load tester at harbour freight cheap.
- The Odyssey battery requires a high rate of charge (My Odyssey charger puts out 7AMPS) and an end voltage of 14.7VDC. Most standard auto chargers do not go this high and stop charging at 14.2 which leaves the Odyssey at less than a full charge. When not fully charged lead acid batteries which is what an AGM battery is will sulfate and this leads to failure.
- If you want your Odyssey battery to charge properly and fully in an oilhead you need to modify the alternator output diodes or do as I do and recharge it fully when you get home from rides with an Odyssey approved charger. I have over 8 years service in my 1100 doing just this and leaving the alternator stock. If you want to charge it fully onboard an airhead get a digital adjustable voltage regulator and dial it up to 14.7 VDC to keep your Odyssey fully charged. You can get one of these at Euromoto Electric and from Rick Jones at Motorrad Electric and they are not expensive and easy to install and dial in.

Everything Michael just wrote is absolutely correct. That said, it fails to account why a battery would have as large a voltage drop overnight or in 24 hours as was tested by the OP.

I have an Odyssey I keep on the bench for electrical testing and somesuch. I don't worry about it being peaked out over 14 volts and it still only drops a few 100ths volt in any 24 hour period. It took 14 hours to pull down to 4v with a headlight bulb attached.

Looks like it was a faulty battery. I swapped it out last night for a new one and things are now working fine. But... Now the bike won't turn over even though it sounds like it has a strong charge. Based on what I've read, assuming it must be a gas/air/plugs issue with either the carbs or the spark plugs.

PGlaves said:

Everything Michael just wrote is absolutely correct. That said, it fails to account why a battery would have as large a voltage drop overnight or in 24 hours as was tested by the OP.

I have an Odyssey I keep on the bench for electrical testing and somesuch. I don't worry about it being peaked out over 14 volts and it still only drops a few 100ths volt in any 24 hour period. It took 14 hours to pull down to 4v with a headlight bulb attached.

Click to expand...

armartel said:

Now the bike won't turn over

Click to expand...

What does that mean? You hit the start button and the starter doesn't even turn?? Or do you mean the engine won't catch and start when you hit the button?