Last weekend, first time I got to go on a significant ride on my recently-fixed GS, it wouldn't start after an hour long ride. Battery was dead, or mostly dead. I wouldn't have been surprised if the battery was low after getting the bike back from a month-long stay in the shop, but one would think an hour long ride would be enough to charge it fully. I could have sworn I read somewhere on GStwin.com that these bikes don't really like to charge the battery under about 4K rpm. Is that correct?
FWIW I charged it and rode again several times since then including a couple of additional longer rides, several 30-45 minutes or more, all of which I made an effort to keep the revs above about 4K while cruising. So far it's starting fine. I just hate to risk getting stranded.
Hey mr72, I've had an experience just recently with a bit of battery weirdness. I'm sure others here will be able to add to, or argue with, this post.
I say weirdness simply because it was never enough to stop the bike from starting. I live in a very mild climate and my bike usually starts from 'cold' with just the gentlest, minimal press on the starter button with the choke on full. A while ago it was taking two attempts to start it. I'm sure most people wouldn't even consider this a problem, for me it was an unexplained change in behaviour - weird.
Two things working in concert contributed to the weirdness. First, the after-market battery I installed a year ago has the vent on the left rather than the right hand side. Not really a problem, a short length of tubing and it fitted. The vent is on the earth / negative / cathode side of the battery. Second, I've been told by a source I trust that the cell nearest cathode is a wet acid battery tends to vent water vapour faster than the other cells in the battery. On this battery the left hand cell vents faster and has easiest access to the vent tube - hence greater evaporation.
These two elements conspired to create the situation where the cell on the left hand side was low on fluid. Although the bike was putting out 14.4 ish volts at 3000rpm the battery wasn't effectively capturing the charge. I topped up the battery, gave it 24 hours on a reasonably 'smart' charger - problem solved.
I have read the same thing. The batter will only charge around 4kish. I can't confirm or deny this, but I will say that most of my trips are short commuter trips to work and back of a few miles and it's all slow speed zones where my RPMs stay below 4k. Luckily I haven't had a problem thus far. 4k RPMs in 6th translates to about 50 miles per hour and the areas I ride through the week to and from work are all 25-45. I suppose if i were to become an issue, a person could always just ride in a lower gear that would achieve 4k during short commutes at lower speeds to ensure charging takes place. Anyone else want to chime in on that assumption?
Here's what the service manual says:
(http://i598.photobucket.com/albums/tt70/rmyers104/Screenshot_2016-11-16-02-14-43_zpsfogl8wg6.jpg) (http://s598.photobucket.com/user/rmyers104/media/Screenshot_2016-11-16-02-14-43_zpsfogl8wg6.jpg.html)
Fully charge the battery and load test it.
Quote from: sledge on November 16, 2016, 03:26:53 AM
Fully charge the battery and load test it.
I have to agree with sledge here. Make sure the battery is actually holding a charge before you try to diagnose a charging problem.
As some of you may have read in my thread a while back, I recently left my key in my bike in the "on" position and completely drained my battery. I jumped it enough to start, but it died while idling. The only time that the bike wouldn't die was if I kept the RPMs up in a higher range (don't remember exact numbers though).
This seems to support the idea that the charging system only really kicks in at >4K RPMs. However, before you worry about the charging system, you should ensure that the battery itself isn't the cause of the problem. Usually batteries go bad much sooner than the charging system.
Yeah thanks for the input. The battery is nearly new and it absolutely holds a charge, pretty sure that's not the problem.
I'll do the charging system check. I have a lot of electrical work to do on the bike anyway.
Also agree with ya on the month long stay at the shop. probably had a ton of cranks during diagnosis and trouble shooting and testing at the end. Maybe left it in a weak condition. My new battery was flat after just an hour or two with the key accidentally left on. a good charge over night on trickle and it hasn't failed me since. Topped it off with some distilled as well. But never hurts to run a meter over it.
Yep, I figured the month long shop stay was most of the problem, coupled with the fact that when I picked it up, they started it just to move it out front like 50 feet, then started it when I got there in the parking lot to demonstrate that it was in fact running, shut it off immediately, then I started it again and shut it off right away before starting it and riding it home 1.5 miles. That's a lot of starting with no charging. I am guessing that, coupled with the long ride with the light on but not enough revs to charge, really left the battery flat.
I notice the charging system check calls for running it at 5K rpms. Can anyone confirm that it really does not charge sufficiently, by design, at <4K rpms? I can always measure the voltage while it's running at idle or 2K rpm but the question is whether that's an indicator of a fault or normal operation.
I believe the GS500 starts charging at about 2000 rpm depending on demand. Here's an old thread on the subject:
http://gstwins.com/gsboard/index.php?topic=40477.msg454644
Quote from: gsJack on November 16, 2016, 01:44:11 PM
I believe the GS500 starts charging at about 2000 rpm depending on demand. Here's an old thread on the subject:
http://gstwins.com/gsboard/index.php?topic=40477.msg454644
Thanks for that. Good stuff in there.
thanks Jack. great info as always. appreciate your insight and replies.
Well it wouldn't start again today after ~120 miles of riding, probably started 10 times. I was persistent in running it at >4K.
Weekend, will check the charging system. Thanks for the info guys. I think yet another thing may be broken on my GS.
Fully charge then load test the battery. Its the weakest most unreliable part of the charging system, assume nothing!!
Static voltages mean very little, its the batteries ability to deliver current when subject to load and voltage drop that matters.
Yes.....the problem could be further up the line but a duff battery can confuse dynamic test figures and make it look like the reg/rect is faulty. It has to be checked, if only to rule it out.
I use one of these, its an invaluable piece of kit.
http://www.drapertools.com/product/53090/100Amp%20Battery%20Load%20Tester
Great info sledge. thank you.
I haven't load-tested it yet or checked out the charging system due to a lack of time today.. but! I did charge it overnight and the battery has me a bit mystified. It's been at 13.6 volts for 6 hours since pulling it off of the charger. I haven't measured it when it's 'dead', but if it's much over 12.5 volts then I can see why the GS has a tough time charging it. If my bike's charging system is on the low side of normal, then it may not produce enough voltage to charge that 13+ volt battery consistently unless it's really revving.
Google for...deep cycle faults and......sulfation. See if the symptoms match up.
A difficulty in accepting and holding a charge does not necessarily mean the generator or reg/rect is faulty and the test procedures all assume the battery is healthy.
Just because the battery looks new means nothing, it could have been left uncharged for a year before you got your hands on it........... you just don't know :dunno_black:
Last time of saying.........."Take it to a shop and get it load tested"...... most places do it FOC. If it comes back good move on to the reg/rect and the stator ........otherwise you could be wasting time, possibly money chasing non existent faults!!
Josh, you can take the battery to Auto zone or wherever - they all can do a load test on it.
I agree with Sledge. The battery is also the easiest and probably cheapest component to replace and eliminate from the troubleshooting process. They are not designed for full discharge/recharge (unless it is a deep cycle battery) and will nosedive quickly if that happens.
Yeah I wish it was the battery. When I said it's almost new I didn't mean I think it looks new. I have the receipt from the previous owner. It's pretty much new. And it also tests good. I took it over and had it load tested.
I am still mystified as to how a fully-charged 13.6v battery can be charged by a system rated only at 13.5 volts. I'll do the test charging system test tomorrow.
The PO did replace the regulator/rectifier unnecessarily while trying to sort out an ignition problem, and I have a spare. Also he did a lot of questionable wiring mods, which I intend to undo. So it's entirely possible there is some wiring problem or the regulator/rectifier needs to be replaced. Just have to check everything out.
FWIW, I put a meter on mine this morning. 12.6v not running. Running, idle 12.9v, 2000rpm 13.4v, 3000 and above 14v
Hope that is of some help.
Mike
Quote from: Sandgroper57 on November 19, 2016, 07:42:28 PM
FWIW, I put a meter on mine this morning. 12.6v not running. Running, idle 12.9v, 2000rpm 13.4v, 3000 and above 14v
Hope that is of some help.
Mike
Thanks. Sounds like yours is healthy :)
Well, good news and bad news.
Good news: my battery is not only good, but it's incredible. That's because ... you guessed it! It has not been charging at all.
I tested it today. It was 12.6 volts when it was 56 degrees this morning and the bike started right up. It revved to 5500rpm due to being on choke and the voltage was ... 12.6 volts. Rev above 5500rpm? 12.6 volts. Steady, solid, 12.6 volts.
I investigated further and found the connector between the alternator and the reg/rect was MELTED. And the wiring coming from the alternator was melted together. So the alternator output was shorted. My guess is it was this way when the PO determined the original reg/rect was bad and replaced it. Then he probably figured the battery was bad because it would "not hold a charge" (taking Sledge's advice, I suppose... I see Sledge responded on the PO's thread on this same issue) and replaced it with the current nearly-new AGM battery which holds a charge great. Probably will start the bike 20 times and run 100+ miles with the lights on etc. before needing to be recharged.
Anyway, with any luck the alternator and reg/rect are not actually bad, just the wiring. There's lots of frayed wires, wires with insulation worn off, etc. So I'm going to spend tomorrow morning straightening out the wiring and then I can see whether the alternator or reg/rect are any good.
There's not a good emoticon up there to describe my frustration with the PO. But, c'est la vie. I'll fix it, just like I did everything else.
If you are lucky the problem is just poor/dirty connections on the plug.
If you are unlucky the problem is in the generator. Shorted turns breaking down between each other, unbalanced voltages on each leg, overheating etc.
Time and your next move will tell :thumb:
It's not dirty connections. The connector is melted and fused together. I'm going to have to cut it out and crimp new connectors on.
In that case the stator winding is faulty. Its delivering unbalanced voltages across each leg, probably braking down between turns when hot. The system is seeing high and unbalanced currents, the plugs are overheating and melting as a result and the reg/rect is running home to mummy.
Replace the stator.......and the problem will go away. I promise you :thumb:
I'll test it but it seems likely that the insulation on the wires wore through and it may be an old fashioned short on the stator side of the connector. All of the heat seems to be on that side. But who knows until I test it.
Fwiw stator test checks out. Will replace the melted connector tomorrow and check the r/r.
Stator might test OK statically but what about dynamically?
Using a 6/9v multimeter to check phase resistances and insulation resistance with the stator at ambient temperature won't tell you much. The phase resistances are that low its unlikely you will detect shorts with a multimeter, for that you need a Ductor tester. As for IR, again it might be fine at 9vDC but whats it like with 90vAC going through it?
Before you can say its ok you need to know is how the stator is behaving when its hot, been operating for a couple of hours and subject to full load voltages and currents in each leg :thumb:
FYI, I chunked the length of wire with the 3-prong melted connector on one end and bullet connectors on the other, and just crimped bullet connectors directly to the R/R input cable. Simple as that, eliminates about a foot of what looks like 16ga wire.
Fired it up and it's ~14V at idle and ~14V across the rev range up to about 5K. It was early in the morning, I didn't test above 5K. But this confirms it will charge my AGM battery (13.6V when fully charged) so we're in good shape.
Sledge, while I would like to appreciate your input, I really don't. Because it's condescending 100% of the time, wrong at least 50% of the time, and nearly always useless in terms of a shade-tree mechanic's ability to act on it. I followed the factory manual procedure for checking out the charging system and it checks out 100%. If it's good enough for Suzuki dealer mechanics, it's good enough for my garage. Others reading this thread, make up your own mind.
Melted connectors between the regulator/rectifier and stator on motorcycles seem to be extremely common, even across brands. It's plainly obvious that localized heating of the connector caused this most likely due to corrosion from galvanic effect causing heat in the connector. Eventually this heat dissipates down the wires and melted the insulation a few mm from the connector on the stator side, causing the stator to short between two of the three wires and produce insufficient AC voltage for the charging system to work.
Anyway to answer my own original question, at least on my bike, when it is working correctly, it will charge at idle, and across the rev range. There seems to be no need to hold high revs (>4K as previously suggested) to get it to charge. :thumb:
Well if you want to believe that ALL stator faults can be identified with a 9v multimeter and attempt to convince others that you are right, and you are prepared to accept yours is 100% serviceable despite some very strong indicators to the contrary......I will accept that :thumb:
Just stumbled across this and wanted to add it to this thread for search purposes:
http://gstwins.com/gsboard/index.php?topic=38480.msg431967#msg431967
Quote from: ShowBizWolf on November 29, 2016, 08:32:37 PM
Just stumbled across this and wanted to add it to this thread for search purposes:
http://gstwins.com/gsboard/index.php?topic=38480.msg431967#msg431967
Thanks for that. It mirrors the factory service manual procedure and is precisely what I did.
BTW in my case the regulator rectifier plug with the two yellow wires was melted together with the plug from the alternator on the other side and the alternator wires had melted insulation right where they come out of the plug. I just cut off both sides and put bullet connectors on the regulator rectifier side to connect directly to the stator wires pictured in the first test, eliminating the pigtail. 150 miles, so far so good.
@mr72,
Easy tiger, don't take offence, take a gate ;¬)
This info is probably no longer relevant to this thread, but I thought i'd toss it out anyways for anyone that can use it. I spoke to a Suk dealership mechanic and he said that it will indeed charge at idle depending on the shape of the battery and it's not putting much back in the battery at idle, but the optimal charging takes place around 2.5-3k, supporting the link that Jack made. Cheers all :)
Quote from: SirHansford on December 04, 2016, 04:41:04 AM
I spoke to a Suk dealership mechanic and he said that it will indeed charge at idle depending on the shape of the battery and it's not putting much back in the battery at idle, but the optimal charging takes place around 2.5-3k, supporting the link that Jack made. Cheers all :)
I think it also depends on the battery type. AGM batteries were not installed from the factory in 1989 so the old charging system may not produce enough voltage to charge one that is not almost dead at idle.
The manual says iirc 13.5-14.5 volts at 5k rpm and my fully charged AGM battery is 13.6 volts so if you have a battery like this and your charging system us at the very low end then it won't fully charge your battery and likely won't charge it at all at idle. But an old fashioned wet cell probably will charge just fine.