Diagnose this electrical fault, flickering lights / no start

[Paul2129]

Hi guys, I'm hoping you can diagnose this problem. I bought a CG125 a couple of years ago now, it is a 2006 and has 18,000 on the clock. When I bought it, the battery was knackered, the starter would barely turn over, it went very slow, but was fixed when I replaced the battery. This has been fine for the last 2 years and 9000 miles. I bought a new bike and use this one around once a week or so.

I found that the starter would just click and there was no action from the starter (once every 20 presses it would start like normal) I charged the battery ( my Optimate indicated no battery issue) but the starter still just clicked. I kept using the bike by bump starting it while I planned to make time to try and fix what I thought was a gummed up starter motor (seen a fix for it on YouTube)

Today I took the bike on a 70 mile ride up the motorway, left it parked up for a while and came to ride it home in the dark. I find that all the lights flicker, indicators pause, glitch, or flash slowly, and the instruments are flashing randomly dim to bright, it's not in relation to engine revs.

I didn't check voltage at the battery, or what it's doing when it's charging. I will do that tomorrow and report back

Can anyone comment on what they think this is ?

Maybe high revs on this long ride caused the reg/rec to under/overcharge the battery to start these weird symptoms ? But if that's the case, why wouldn't fully charging the battery make the starter work ?

Please post your thoughts, I'll report back with voltages tomorrow

Paul

[Wull]

My initial thoughts made me think the starter switchgear was needing stripped down and cleaned,faulty kill switch!

Will be easier to diagnose after you report back with you readings.
____________________
"Scooters are for men who want to ride motorcycles but prefer to feel the wind on their vaginas"

[WD Forte]

I'd start by checking the battery terminals are clean and tight
then the earthing starting where the battery neg goes to frame and loom.
Honda usually use green wires for earth
than open, inspect and clean all the other connectors and fuse holders
A squish of switch cleaner would help too.

If the symptoms persist
You could also try running the bike on the main stand in neutral
and wiggle,fiddle and tap the wires and switches around the bike
to see if disturbance in any one area makes it happen again or
makes it worse/stop.
____________________
bikers smell of wee

[Taught2BCauti...]

I would:
1. Check battery voltages off the bike, before and after a charge.
2. Check resistance of alternator windings (usually 3 coils to check).
3. Check resistance across switches (whilst battery is off).
4. Check battery voltages on the bike, with engine off, and engine running @ 2000rpm.
5. Check all earth connections.

Might be a Reg/Rec problem?
____________________
Honda Varadero XL125(V8)
www.TheFutureIsHere.eu

[Paul2129]

Ok, I can report battery voltages. Bear in mind that last night I acted like it was flat

12.2 with the engine off

13.5 high tickover, 13.9 mid revs

Thanks for the suggestions so far, keep them coming

(If we have almost 14v, doe that mean the alternator is working and doesn't need to be checked ?)

There must be something in the fact that the long ride caused these problems, reg / rec problem maybe ?

[Taught2BCauti...]

12.2v with the engine off sounds a bit low - is it the same when disconnected from the bike?

A good battery will hold over 13v after being charged, but if it drops down to 12.2v when re-connected, then something must be drawing current.

If there's nothing switched on, a faulty Reg/Rec could cause current to flow back through the alternator windings.

I had a similar problem on a car a few years ago - I charged the newish battery off the car, but after re-connecting it, the voltage dropped below 12v after 30 minutes. As I was checking the wiring, I noticed the alternator was quite warm even though the engine hadn't been running. Replaced the Reg/Rec (part of the alternator on most cars, but a separate unit on bikes) and that fixed it.
____________________
Honda Varadero XL125(V8)
www.TheFutureIsHere.eu

[Paul2129]

When you say 12.2v is a bit low, bear in kind that it appeared to be flat last night, I'm surprised it's 12v to be honest

[Taught2BCauti...]

[Wull]

12.2v is low but it should still crank the engine over and get the old girl purring.

11.7v is the point in which it will fail and not produce enough juice to turn the engine over.

Do you have access to a battery charger?

If so I'd remove the battery,charge it fully then leave over night and keep a note of the voltage?

Also its worth while taking a voltage reading with the lights on,it could be that when your lights are on the charge rate is too low to charge the battery as much as it should be.
____________________
"Scooters are for men who want to ride motorcycles but prefer to feel the wind on their vaginas"