New bike lasted 26 miles 😥

[Rockeye]

Good evening all

Wondered if I could pick your brains?

I bought a lovely 1996 ST1100 (Stunning condition in Black-was part of a private collection) only a month ago but due to work commitments I didn’t get chance to ride the bike until the 23rd of December. I volunteer for the Blood bikes delivering around hospitals and whilst on my way from the local cancer hospital the bike completely died on me leaving me stranded at the roadside.

The symptoms were, initially she was running beautifully but then started to cough and splutter as if running out of fuel, I pulled over and managed to keep the bike running by turning the headlights off at which point she fired back into life running beautifully once again. The bike ran nicely again for several miles before dying in busy traffic, I managed to push the bike to the side of the road and had to have the bike recovered home.

Once home I’ve charged the battery and she’s running beautifully again, I’ve tested to see if the bike is charging and unfortunately it isn’t! I’ve looked online and seen the “Red wire mod” but not sure if this would cure my problems?

Would anyone on here be able to shed any light and help out with this for me as currently I’m bike less and unable to ride for the Blood bikes. If it’s a large repair job I’m tempted to contact the seller as the bike was MOT’d before delivery and I can prove I’ve only ridden 26 miles before breaking down, I actually asked him was it reliable as I’d be using it for Blood bikes and he assured me it was. Annoyed is not the word

Thanks for any assistance you can provide.

 

[Erdoc48]

I would check the battery condition first…if you can prove it’s a good battery, then look further- check the main 55A fuse in the black plastic box next to the battery and make sure that’s not broken (if it is, like you said, the battery won’t charge and you’re running off the battery and will get stuck when riding again). So it does sound like primarily an electrical issue in your case. The red wire mod is to correct an issue when the affected wire gets corrosion on it and disables the bike (and is easy to do as well).

 

[Rockeye]

I would check the battery condition first…if you can prove it’s a good battery, then look further- check the main 55A fuse in the black plastic box next to the battery and make sure that’s not broken (if it is, like you said, the battery won’t charge and you’re running off the battery and will get stuck when riding again). So it does sound like primarily an electrical issue in your case. The red wire mod is to correct an issue when the affected wire gets corrosion on it and disables the bike (and is easy to do as well).

Thanks for you reply Erdoc48 I’ll look into those and see if I the fuse has blown, I’m guessing the red wire mod is for a bike that won’t start as opposed to mine that’s not charging ?

 

[Uncle Phil]

Across the battery posts you should get a reading of about 14.6 volts when the bike is running.
The battery should read 12+ volts with the switch off.
If you are not getting 14.6 then you have to chase the charging circuit backwards to see if there is corrosion or you have a failed alternator.
A 96 would have the 40 amp alternator and on your side of the pond, the 'acid' they put on the roads in winter can eat one of those up.
How many miles on the ST1100?

 

[Rockeye]

Across the battery posts you should get a reading of about 14.6 volts when the bike is running.
The battery should read 12+ volts with the switch off.
If you are not getting 14.6 then you have to chase the charging circuit backwards to see if there is corrosion or you have a failed alternator.
A 96 would have the 40 amp alternator and on your side of the pond, the 'acid' they put on the roads in winter can eat one of those up.
How many miles on the ST1100?

Hi Uncle Phil

I’ve tested the battery and it sits static at 12.3 volts, started the bike ( charged the battery after recovery home) and when revved to 5000 rpm it still reads 12.3 volts sad.y so looking like it’s not charging.

The bike is in beautiful condition, almost as good as new ams only has 26,000 miles so I’m surprised at the fault. It looks like it has a new battery fitted so guessing the seller knew it had the issue and popped a new battery on it to get it away. The 40 amp alternator has the reg/rectifier built in I believe so looks like it will be a swingarm out to get to it if needed.

 

[motornut]

Along with the static battery readings, if your meter has a MIN/MAX reading. Get a reading at the cranking voltage, it should - never -be below 9.6 volts, and normal full charge is cranking is around 10.5 or more. I have run into times when a loose battery cable causes intermittent problems.
Now would be a good time for all of us to invest in fuel pressure gauges that fit our automotive and fuel injected bikes.
Wait a sec....am I stuck in FI mode. Had to go check, yep it is injected.
With the prevalence of FI having a gauge is no longer a bad idea, the gauge can help diagnose a host of difficulties. Even if it only separates fuel from electronics. Not being able to see fuel pressures makes a fuel mystery, cracking a line to see if there is fuel no longer guarantees the correct pressure whether cranking or running. Personally, I have not run into a lot of fuel problems. but have been able to look beyond fuel easily by checking pressure.

 

[motornut]

I also need to start reading more, your way past finding out where the problem is. You are in phase 2. You know what is wrong and on your way to repair

 

[St-Gerard]

Start with the simple things first, clean Grounds, and check fuses and connections for corrosion and not plugged in all the way. 26000 miles alternator should not be worn out.

 

[Uncle Phil]

Before you go through pulling the swingarm (you will need a special tool), as I'd start from the alternator end to see if it is outputting anything and then move toward the battery to see if there is a failed connection.

 

[jdmccright]

Hi Uncle Phil

I’ve tested the battery and it sits static at 12.3 volts, started the bike ( charged the battery after recovery home) and when revved to 5000 rpm it still reads 12.3 volts sad.y so looking like it’s not charging.

The bike is in beautiful condition, almost as good as new ams only has 26,000 miles so I’m surprised at the fault. It looks like it has a new battery fitted so guessing the seller knew it had the issue and popped a new battery on it to get it away. The 40 amp alternator has the reg/rectifier built in I believe so looks like it will be a swingarm out to get to it if needed.

Sounds like the alt isn't charging. A shame, but unfortunately it can happen with older bikes, even the ST1100. New and rebuilt ones can be had for $250-300, and I would look into the red wire mod to eliminate that potential issue. Those two and the vacuum-operated fuel shutoff valve are probably the big ones that can stop an 1100. But as @Uncle Phil noted, check that there isn't a wire break before tearing into it.

Maybe the PO knew about, maybe not, but on the level a failed alt is less likely than the other two I've mentioned and not always noticed except on long trips. GL!

 

[Ron]

The corrosion on the red wire can cause intermittent problems. I don't know if it will cause the bike to not charge.

 

[Slydynbye]

Check for 12.3 volts at the connector that plugs into the back of the Alternator. 2 wire white connector with a black and white wire. Also unplug and check for corrosion.
My understanding is that unless there is voltage present there, there will be no output from the ALT.

 

[Rockeye]

Along with the static battery readings, if your meter has a MIN/MAX reading. Get a reading at the cranking voltage, it should - never -be below 9.6 volts, and normal full charge is cranking is around 10.5 or more. I have run into times when a loose battery cable causes intermittent problems.
Now would be a good time for all of us to invest in fuel pressure gauges that fit our automotive and fuel injected bikes.
Wait a sec....am I stuck in FI mode. Had to go check, yep it is injected.
With the prevalence of FI having a gauge is no longer a bad idea, the gauge can help diagnose a host of difficulties. Even if it only separates fuel from electronics. Not being able to see fuel pressures makes a fuel mystery, cracking a line to see if there is fuel no longer guarantees the correct pressure whether cranking or running. Personally, I have not run into a lot of fuel problems. but have been able to look beyond fuel easily by checking pressure.

Hi Motornut

Thanks for your reply, the ST1100 has carburettors so no FI on this bike sadly, I’m pretty sure the bike isn’t charging which is strange for such a low mileage bike in beautiful condition. The seller advised he got the bike from a personal collection and this is commensurate with it’s condition.

I ride a marked R1250RS BMW for the Blood bikes, but also use my own bikes when time is tight to get a shift in, the Pan rides smoother than the almost brand new BMW and in all honesty I prefer it ( well in the 26 miles I got in on it)

 

[Rockeye]

The corrosion on the red wire can cause intermittent problems. I don't know if it will cause the bike to not charge.

Hi Ron

Yes this was my thinking, I can’t see any corrosion on the starter connection.

 

[Rockeye]

Check for 12.3 volts at the connector that plugs into the back of the Alternator. 2 wire white connector with a black and white wire. Also unplug and check for corrosion.
My understanding is that unless there is voltage present there, there will be no output from the ALT.

Hi Slydynbye

Thanks for your reply, I’ll try to get under the bike and get to this connector and see if there’s a voltage there along with any corrosion.

 

[Rockeye]

I’ve just done a little more digging and spoken to the seller who’d put a new battery on the bike ( he’s a motorcycle transporter who buys and sells bikes too) -he suggested looking at the main fuse (55A) and what a surprise it looks like that’s the culprit.

It does worry me how he knew straight away to go there unless it’s just experience? Quick question what would cause this to blow as it’s a fairly hefty fuse at 55A? Here’s a picture of the blown fuse.

 

[motornut]

Hi Motornut

Thanks for your reply, the ST1100 has carburettors so no FI on this bike sadly, I’m pretty sure the bike isn’t charging which is strange for such a low mileage bike in beautiful condition. The seller advised he got the bike from a personal collection and this is commensurate with it’s condition.

I ride a marked R1250RS BMW for the Blood bikes, but also use my own bikes when time is tight to get a shift in, the Pan rides smoother than the almost brand new BMW and in all honesty I prefer it ( well in the 26 miles I got in on it)

Thank you for straightening me out. It may not be a alternator problem yet. I am leaning toward something switch wise or wiring not supplying the alternator the juice to turn it on. But that is what trouble shooting first is all about
and, you are starting down the road in the right direction by checking everything around the alternator. Like the voltage from the ignition and such, I have no doubt you will figure it out.
The neat thing about being familiar with the system is that you can come up with ways to trouble shoot.
I have an ST and a 2015 Concours 14, drives me nuts trying to ride them both, when I am on one I want the other, one for power and handling and the other for comfort and easy operation. I have a ZRX 1200 that has one of the most usable engine I have ever been around, If I could get that engine in the ST and the handling with the top end in the ST I would be in heaven.

 

[kiltman]

I think it’s the main relay connector. On the left side of the bike below and to the front of the bike near the battery you should see a soare green 30 amp fuse pull back the rubber boot behind it to reveal a red connector. Open the connector and inspect the terminals. I suspect that the connector is melted. The red wire will be the culprit.
You can replace the connector or in the meantime replace the connector with female spade connectors. Take note of the orientation of the three wires. You will need to make sure you connect each one to the corresponding terminal, if you don’t you will blow the clutch diode, and the neutral light will stay on.
You may also need to cut back the red wire because of the corrosion. Simply splice in a new section of red wire to compensate.

 

[St-Gerard]

I’ve just done a little more digging and spoken to the seller who’d put a new battery on the bike ( he’s a motorcycle transporter who buys and sells bikes too) -he suggested looking at the main fuse (55A) and what a surprise it looks like that’s the culprit.

It does worry me how he knew straight away to go there unless it’s just experience? Quick question what would cause this to blow as it’s a fairly hefty fuse at 55A? Here’s a picture of the blown fuse.

A couple of things can cause that fuse to blow, a battery to discharged, alternator's don't have a amperage limiter, only voltage. So when the battery is low the alternator will crank out enough amps to melt that fuse/ or it self. I do have to look at a wiring diagram to see if I'm correct about power from the alternator going through that fuse. Second, the metal they use , is fairly brittle, I have hit a big pothole that broke the fuse, but that's another story. Short to ground in the wiring, hopefully not. Oh yeah jump starting the bike with a running car. Speaking of all this going to get a spare fuse for my bike.

 

[Erdoc48]

The only time my 55A blew is when I tried to jump a bad battery with jumper cables and my car (and did gets some sparking at the battery terminals)- the battery was that flat- I had the bike completely die (this is the 2000 ST) ~ 10 miles from the house (lots of backfiring through the carbs as I guess not enough power to light the spark plugs for forward motion). I had the Mrs bring me back to the bike with a new battery after storing the bike overnight at a construction site. Dead battery again. Did a little digging and it was the 55A fuse that was blown. Replaced that, charged up the new battery, and all was good. Replace that fuse and if it blows again, you need to do a little more digging (like the alternator isn’t putting enough charge to the battery as others have said above). Hopefully the new battery the prior owner said he replaced isn’t fried, but if it is and that’s all good now, then you’re done. Another test would be to replace the fuse, replace the battery, and test- if all is good then, maybe that battery had internal faults not allowing it to charge fully (had that issue on the 94 a couple of years ago- very strange, just died on a ride, completely flat). Swapped that battery, the bike was fine, but with the old dead battery out of the bike, it was showing voltages all over the place- 12.3V, then 8.9V, then 11V with alligator clips on the terminals and me just watching (like variable voltages). That battery was only I believe 3 years old and was an AGM type.

Basically, replace the fuse, use a known good battery, and if still having issues, then yes, it may be the alternator. Also, it looks like some minor rust in there with your pic. Maybe Scotchbrite that area so the metal has no resistance to current flow.