Overheating or stator?

[geluso]

I'm out riding around my first bike after buying and getting her running. I've done repairs to the clutch. Things are running fine.

I rode for about twenty minutes today beside the lake in Seattle in 74 degree weather. Eventually the bike shut off while I was running. My battery didn't have enough to start again.

The previous owner said there were problems keeping the battery charged. I've measured the charge going to the battery and read it at 12.8 when the motor is running. I brought a voltmeter and an extra battery with me today. the battery red 11.8 when the bike stopped running.

I replaced the battery with a fresh one reading 13.4V and the bike started right back up. I was able to ride for about a mile back toward home for the bike abruptly stopped again. I measured the fresh battery and it currently reads 13V.

Although the first battery certainly drained, this feels like overheating to me. Right now I'm sitting by the lake allowing the bike to cool off before I try to ride again.

Any tips about how to diagnose overheating?

I will investigate the stator when I get home.

 

[Jim]

Any tips about how to diagnose overheating?

I will investigate the stator when I get home.

Look in Tech and you'll find a charging system troubleshooting thread. Follow that and ask questions, then go from there.

Fwiw, the stator's on these bikes almost never break. It's the rotor that usually gives up.

 

[Jim]

https://www.xs650.com/threads/rewound-alternator-rotor.54276/post-584935

 

[geluso]

I was just able to ride 1.5 miles closer home. I'm at an O'Reilly's now which is nice. The bike shut off while idling for a minute behind a car at a red light.

the battery currently reads 12.94V.

Still suspecting overheating.

 

[gggGary]

Year and type of ignition?
there's at least 5 or 6 different kinds of ignitions commonly used on these.
If your charging is OK, (a digital voltmeter on the handle bars a very good idea) a bad coil going open circuit when hot is a possibility. condensers can fail but that's not their most common epitaph.
As is a plugged gas cap vent, plugged fuel filter, sediment in a float bowl.
Unless you have very advanced ignition timing (kick backs usually indicate this, or severely scored cylinders, which will usually show up as poor compression, overheating is pretty far down the suspects list on an XS650.

 

[geluso]

OK thanks for cluing me in overheating is likely not the issue.

I just got home after letting it sit for another 45 minutes and grabbing food.

I'm measuring the voltage while it's running now and it is only 12.8V. I'll go through the troubleshooting linked by everyone.

thanks!

 

[geluso]

Jim, thanks for your clear instructions with the slap test. I appear to have no magnetism. Continuing following instructions. Will report back.

 

[Jim]

No magnetism at the rotor could be the brushes, the rotor, the reg or wiring. Like Gary said above, we need more info. Pics will help if you don't know what charging and ignition system you have.

 

[geluso]

Here's me looking at the stator this evening. I can take more photos tomorrow morning.

 

[Its been a long time]

Here's what I would do next.

Pull the carbon brushes to check them (new ones aren't expensive). While they're out measure the resistance in ohms across the copper rings of the rotor.

Tell us what you find, post pictures. They always help. Folks here like pictures.

 

[gggGary]

The TCI ignition is kinda voltage sensitive, as the battery voltages drops it starts missing then quits completely. After a short rest the battery recovers enough to let it run again for a bit.

 

[geluso]

Photos! I measured 5.7 ohms across the copper rings of the roto.

 

[Its been a long time]

OK. The reading is slightly outside the normal range of 5 to 5.5 ohms. It might be worth giving the copper tracks a light clean to see if that drops the resistance a little. It's likely your rotor is good, I think.

I can't tell from the pictures what the condition of the carbon brushes is like. They're cheap to replace anyway.

I think you need to follow the excellent trouble shooting guide. Looks to me like you will soon get that charging.

Next thing I would do is the tests for the stator windings, it's probably good but the tests are easy to do. Link -

Thread 'Expanded charging system guide (In progress)' https://www.xs650.com/threads/expanded-charging-system-guide-in-progress.10561/

 

[geluso]

Amazing. Working through the guide now. Thank you.

 

[Its been a long time]

In case you're not familiar. The charging system is subtly different on bikes to 1979 and from 1980 onwards. Make sure you're familiar with the parts of the charging guide that apply to the model year bike you have.

 

[geluso]

Here's a better photo of the carbon brushes.

I see the guide mention "the green wire at the regulator plug." Is my finger pointing to the correct wire and plug here?

 

[Its been a long time]

Looks to me like you're pointing at the neutral switch.

I can't see the brushes without them being removed from their holders. I would count on replacing them anyway for the few $ they cost. They are a service consumable item.

Regarding green wire etc.... you need to understand the difference in how the magnetic field of the rotor is regulated because earlier and later than 1980 the regulator works differently and there's subtle differences in how the brushes etc.... function. Make sure to read and understand the 1980 on information because looking at the TCI trigger on the stator it's obvious you have a 1980 or later charging system.

Next, I would do the stator checks on the three white wires as described in the guide.

 

[Its been a long time]

1980 onwards brushes configuration -

Post in thread 'Expanded charging system guide (In progress)' https://www.xs650.com/threads/expanded-charging-system-guide-in-progress.10561/post-507561

 

[gggGary]

That looks like a MikesXS ignition coil. For years they were notorious for piss poor primary connections...

 

[jetmechmarty]

That looks like a MikesXS ignition coil. For years they were notorious for piss poor primary connections...

As a side note, shotgunning with MikesXS parts adds problems not fixes more often than not.