View Full Version : Electrics cut out completely while riding - likely causes?
nerrrd
29th November 2020, 18:05
So on my way home today was happily riding along, everything normal, when the bike cut out altogether and I had to coast to the side of the road.
The bike was completely dead, no dash lights, nothing. No response to turning the ignition key, nothing from the starter. I checked the battery connections which were tight and had a cursory look at the fuses which seemed fine to me (but I don’t really know what I’m looking at and may have missed some). Tow truck driver said it sounded like maybe the alternator has died?
Anyone able to shed any light on what the might be problem so I can work out what to do next? Bike is a 2014 Honda NC750X with 40,000kms on the clock.
Many thanks in advance.
onearmedbandit
29th November 2020, 19:21
If it was a fuse, it would be the main fuse if everything died. Which is typically located near the battery and main electrics, not in the normal fuse box. And if that fuse has blown you will want to know why.
nerrrd
29th November 2020, 20:17
If it was a fuse, it would be the main fuse if everything died. Which is typically located near the battery and main electrics, not in the normal fuse box. And if that fuse has blown you will want to know why.
OK great, have located it now due to the wonder that is the internet, will check it in the morning (thanks).
nerrrd
30th November 2020, 08:32
Main fuse looks fine to me. Any other suggestions?
nerrrd
30th November 2020, 10:14
OK so just confirmed the battery won't hold a charge at all, it's a two year old 'Poweroad' Nano Gel one. Didn't realise batteries could fall off a cliff like that.
Bit of a relief, now just have to get a new one.
Jeeper
30th November 2020, 10:29
OK so just confirmed the battery won't hold a charge at all, it's a two year old 'Poweroad' Nano Gel one. Didn't realise batteries could fall off a cliff like that.
Bit of a relief, now just have to get a new one.Modern batteries do often fall off the cliff like that.
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F5 Dave
30th November 2020, 11:47
Other candidates the ignition switch falling apart (had that happen). Lead falling off the battery could produce odd effects.
Alternator failure would eventually stop it but you'd have some residual battery power idiot light etc.
SaferRides
30th November 2020, 13:48
OK so just confirmed the battery won't hold a charge at all, it's a two year old 'Poweroad' Nano Gel one. Didn't realise batteries could fall off a cliff like that.
Bit of a relief, now just have to get a new one.Buy a Yuasa. More expensive but it will last longer and is unlikely to fail like that.
mulletman
30th November 2020, 14:03
Buy a Yuasa. More expensive but it will last longer and is unlikely to fail like that.
Been waiting since July for a new Yuasa....
george formby
30th November 2020, 14:35
Buy a Yuasa. More expensive but it will last longer and is unlikely to fail like that.
Concur. I've had over 8 years on a Yuasa. But see above.
What a state of affairs!
nerrrd
30th November 2020, 14:45
OK so battery confirmed DOA after taking it into AJ at Motohaus (excellent advice as usual) but he didn't have one so ended up having to hike over to Colemans Suzuki who did (just replaced like for like as I'm a bit financially challenged at the moment). Supplies are very constrained all round apparently. New battery is in and bike started first pop and ran happily for five minutes or so.
Feel very lucky that it crapped out when I was on a nice straight road, at the top of a hill, with plenty of room to coast to a stop. Would have been interesting to say the least if it had happened leaned over while accelerating through a corner.
Scuba_Steve
30th November 2020, 15:06
OK so battery confirmed DOA after taking it into AJ at Motohaus (excellent advice as usual) but he didn't have one so ended up having to hike over to Colemans Suzuki who did (just replaced like for like as I'm a bit financially challenged at the moment). Supplies are very constrained all round apparently. New battery is in and bike started first pop and ran happily for five minutes or so.
Feel very lucky that it crapped out when I was on a nice straight road, at the top of a hill, with plenty of room to coast to a stop. Would have been interesting to say the least if it had happened leaned over while accelerating through a corner.
Might be worth your time (just to make sure it was only the batt) putting a multi-meter across it, make sure it's putting out the 14-ish volts when running
caspernz
30th November 2020, 19:43
OK so battery confirmed DOA after taking it into AJ at Motohaus (excellent advice as usual) but he didn't have one so ended up having to hike over to Colemans Suzuki who did (just replaced like for like as I'm a bit financially challenged at the moment). Supplies are very constrained all round apparently. New battery is in and bike started first pop and ran happily for five minutes or so.
Feel very lucky that it crapped out when I was on a nice straight road, at the top of a hill, with plenty of room to coast to a stop. Would have been interesting to say the least if it had happened leaned over while accelerating through a corner.
Might be worth your time (just to make sure it was only the batt) putting a multi-meter across it, make sure it's putting out the 14-ish volts when running
Yep, like Scoober commented, I'd be wondering about alternator and reg/rec. New batteries going DOA in short space of time is odd, but not unheard of.
nerrrd
1st December 2020, 09:20
Might be worth your time (just to make sure it was only the batt) putting a multi-meter across it, make sure it's putting out the 14-ish volts when running
Yep, like Scoober commented, I'd be wondering about alternator and reg/rec. New batteries going DOA in short space of time is odd, but not unheard of.
So is it possible for the bike's charging system to damage a battery over time?
Because the old battery wouldn't hold a charge at all in the bike (even when the bike was jump started and running, as soon as the jumper was disconnected it died), but then showed a full charge when put on a charger. So the general consensus was it was stuffed.
I don't have a multimeter but could pick up a cheap one.
Jeeper
1st December 2020, 09:26
Yes, my battery was cooked because of stator cooking itself which in turn damaged the regulator. Battery died beyond repair. Everything had to be replaced (thankfully bike was still under warranty).
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F5 Dave
1st December 2020, 12:06
You will reach for a multimeter many times in your life once you have one. Don't even need to be terribly accurate for most people. Just keep 240v for electrician.
YouTube will teach you enough for automotive use.
Over say 15v when revved to 3000rpm and your regulator is stuffed. Less than 13.5 when revved and I'd be expecting a burnt alternator (which you can then test as an AC voltage on stator connector unplugged when running) or perhaps a stuffed battery or misbehaving component dragging things down.
Probably just the battery but its worth being educated. Jaycar have a range for many price points.
Jeeper
1st December 2020, 13:05
Trickle charger is another good friend to keep the battery healthy for periods when bike is unused for extended periods.
I use Ctek for the Jeep and bike, keep an eye on Repco for good sales.
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nerrrd
10th December 2020, 09:00
So I picked up a cheap multimeter from Bunnings and checked it out, was reading 14.3 around about consistently when running, revving up to around 3000 it stayed pretty much the same, maybe a .4 increase? (bearing in mind red line is 6500.)
Thing is the bike still isn’t starting as eagerly as I would have expected with the new battery, but so far it hasn’t not started.
F5 Dave
10th December 2020, 12:02
That sounds like the charging is working nicely.
It could be interesting to see what sort of volt drop you are getting to the starter when turning over. The starter relay is supposed to ensure a decent path from the battery to the starter and back via ground. Sometimes the cables can be a bit weedy added to corrosion.
Check specific forums to see if upgrades are common.
Cleaning the starter button can help in some cases. Yes it is off the relay to motor cct but any drag on the system pulls the battery down. Measure how much it drops while turning over is interesting (quite a bit) and can check for improvement.
malcy25
11th December 2020, 16:16
always check your earth too!
nerrrd
21st January 2021, 15:09
So everything's been going ok for the last month or so with my normal daily-ish commuting rides, then I did a Ride Forever course on Monday (around 300kms), after that when I went to start the bike on Tuesday morning not enough charge.
Bike started with the jump starter straight away, managed a few more starts on Tuesday and Wednesday after a couple of rides, then not enough charge again this morning (Thursday). Checked the voltage on the battery (not running) last night and it read 13.3 and again this morning when it read 13. Should have checked the bike while running again but left it too late. Battery is now on a charger being charged overnight.
Bike has quite a few electrical accessories - I disconnected the only accessory connected directly to the battery (fog lamps which I very rarely use) straight away.
Bike came with factory heated grips and USB port. I also had a couple of LED driving lights and a supplementary brake light installed a couple of years ago by an auto electrician. All these accessories are only live when the key is on. They've all been working normally, except for one of the LED driving lights which has recently stopped working. These have a separate inline switch as well (which I switched off when I noticed the failure)
Not sure what to do next.
neels
21st January 2021, 15:23
Start by disconnecting the positive lead from the battery, set your multimeter to measure DC current (on the highest range and work your way down), and put it in line between the battery and battery lead.
If there is anything more than a few mA with the key off, that's why your battery is going flat.
As suggested previously, it would be worth measuring both the DC and AC volts across the battery. If there's a crook diode in the rectifier you'll get some AC volts indicated, and the battery won't be charging properly.
Having said that, if it's showing 13V not running, that suggests that the battery is holding charge. Quick way to check is turn on the headlight and see if it still sits around 12V, anything less it's got a capacity issue.
nerrrd
22nd January 2021, 12:02
So put the charged battery in.
First start was fine, dropped to 9-ish volts when starting then happily ran, was showing 14-ish volts while revving around 3000 (redline 6500).
Switched off and tried to start again, this time dropped to 3 or 4 volts when pressing the starter and wouldn't start.
This may no longer be relevant but tried the current thing earlier, couldn't register any draw in line with the battery with the key off (with the positive connected and the multimeter held between the negative terminal and lead...I'm assuming I did something wrong though, shouldn't there be some draw happening? Or maybe it's the cheap multimeter).
F5 Dave
22nd January 2021, 12:40
Battery is knackered surely?
But charging system appears to be working so happy days there.
Attach some jumper leads to a car battery (don't bother starting the car or that nonsense) and it will fire right up with sod all drop i suspect. Car batteries are of course huge by comparison.
There should be no drain if the ignition switch is working with current test ideally. There could be a tiny amount in some systems to retain a clock but not much. So good.
nerrrd
22nd January 2021, 12:53
Battery is only a month or so old, and is showing 13-ish volts on the meter. I had it charged overnight last night at a local bike place and the lights were all green.
Did some more research online (always dangerous lol) and found a recall for Honda motorcycles for 2014 which now has me wondering.
Honda has determined that a defect within certain starter relay switch assemblies can cause an increase in resistance across the main fuse, potentially interrupting battery voltage to the electrical system which can cause the engine to A) not start or B) stall while riding. In an extreme case, the increased resistance at the main fuse can cause the starter relay switch to catch on fire.
nerrrd
22nd January 2021, 14:09
So got some more advice which agreed with the battery being knackered (even though it's a new one) theory, was going to take it out and then thought I'll just try it one more time to confirm...and it started, dropping to 9 volts. Then tried again, it started again, this time dropping to 7 volts.
Anyway might talk to someone else about it over the weekend.
F5 Dave
22nd January 2021, 15:29
Next idea was to measure the difference in voltage from the starter motor to the battery. I didn't suggest that as it's harder to get to. So one lead on battery + and one on starter input. Push starter. The idea is you will have a thick wire with a grunty relay connection between the two. There should be very little difference so any difference will show on the meter.
If you were losing 0.5v over this connection it would should as 0.5v. Pretty good.
If as suggested the relay is dicky then this may show higher drop so bigger number. A small battery will drop more voltage as it tries to breach the gap.
I've never done this measurement but the logic is sound, just I cant tell you the expected numbers. You might come up with the idea of bridging the high current side of the relay as a test. Mucho sparks, don't try that.
You could however initiate the low current side. This takes the ignition switch and push button out of the equation and that on older bikes is a known weak area I've fixed before. You aren't bridging them in this case, you'd need a wiring diagram to find how to throw the switch.
Older bikes were easier to get to solenoid connections, newer ones have encompassing plugs with fuse as well getting in the way.
nerrrd
28th January 2021, 07:17
Ended up going back to Colemans where I bought the new battery a month or so ago and explained what was happening and they were happy to swap it for another one – excellent service there.
So far, touch wood, that seems to have solved the issue.
Thanks for all the great advice.
F5 Dave
28th January 2021, 12:02
Batteries can be queer things especially in slightly marginal conditions. Like tiny size compared with a car.
I'd still do those voltage drop measurements if you can . You can even unplug and run a thin wire out to get a measurement of volts as there's no current just temporary squashed into a plug.
OddDuck
28th January 2021, 19:07
Possibly a bit late to the party, but if you're still having trouble it might be worth getting a Yuasa (or a Katana, which is a half-price Yuasa made with recycled materials according to the guy at the local battery shop).
I've abused multiple Yuasas over the years. They're tough buggers, it takes a lot to kill them. When they do finally go it tends to be a graceful down-curve with plenty of warnings before the bike finally won't crank.
I've never had one suddenly cut out while riding.
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