First Bike woes - Honda CG125 Electrical problems

[philh88]

Hi All,
I've just bought a 2002 Honda CG125 as a first bike and as a bike novice, am after a bit of advice Unfortunately I've been having issues with it almost immediately. It was delivered to me on Friday, and the seller had sent me videos that day of it starting perfectly off the electric starter, and with all the lights shown working as I requested.

Since getting it home I've had problems in this order:
-Initially wouldn't start on the button, but started instantly on the kick start and ran really well.
-I couldn't get the horn or indicators to work but the headlamp and tail light did work.
-Then the bike started cutting out if horn or indicator button was pressed while idling.
-Eventually the bike refused to start at all and is now completely electrically dead with no spark.
-All that happens if I try to kick start it is the Neutral light flickers.

So far I've:
-Checked the battery voltage -its about 13.5V
-Checked the 10amp fuse by the battery - looks fine.
-looked for loose earth wires/loose connection - found two loose wires in the rats nest of wiring in the headlamp but they don't look newly disconnected.

The fact that it was all functioning and then gradually got worse makes me think maybe a loose earth connection somewhere? I've looked online and had a look at the owners manual but Electrics is not my strong point.

Does this seem like it all could all be from one fault like an Earth? Any advice would be greatly appreciated to help get it running again!

The seller did mention to leave it in gear not in N, or the Neutral Light LED stays on and eventually drains the battery.

Cheers in advance.

[littlebasher]

Sounds more like dodgy ignition switch to me

Get a meter on it and check that there's power going it - and more importantly going out !

[Prof Prolapse]

I'd not have ruled out battery just yet.

Obviously a voltmeter won't give an indication of battery health, and batteries are huge weak points on motorcycles, especially on bikes presumably sat around during lockdown.

Just something I'd want to rule out entirely before looking at more complex problems.

[Alex@POD]

The battery is at 13.5 now, but what does it say when you're pressing the starter button? If it's stays the same, it's a bad connection somewhere, if it drops dramatically, the battery is dead.

[mickyh7]

If its the Ignition Switch, sounds like it could be, get it sorted asap.
If you loose electrical power while turning the bike on the clutch.
You'll be on your backside.
Ignition-attempted theft, new switch bodged in.
Wiring in headlamp- crashed and taped up badly .
Good luck with it.

[philh88]

Thanks for your responses so far.

Alex@POD - I’ve just checked the battery voltage while pressing the starter and there was no drop in it at all so unfortunately I don’t think it’s the battery.

Mickyh7 and littlebasher - I’ve had a look at the ignition barrel and it is in pretty bad shape. It has 4 wires going to it , red, black , black and white striped and green. The rear of the barrel where the wires connect have had some some of black sealant slapped all over it so you can’t see the connections.
However..... about an inch above the ignition barrel, the red wire has an area of damage with bare metal showing and the insulation gone. The wire itself is in pretty rough shape. Reckon that’s a likely cause?

[philh88]

In fact looking closer I can see some bare wire on the black cable too, and signs of melted insulation. They must have shorted together which I think would (hopefully) explain the problems I’m having.

Hoping It’s now a case of cut off the damaged ends, order a new ignition barrel, wire it in an keep fingers crossed.

[Steve Bass]

philh88 said:

The seller did mention to leave it in gear not in N, or the Neutral Light LED stays on and eventually drains the battery.

Does it do this with the key off and removed???

For it to start on the button and slowly decline in performance to not wanting to is indicative of a battery issue, but i'd expect it to fire up when kicked regardless especially as it's a carb'd motor.

You might find that the reg/rec is faulty. It might have come to you with a full battery for show but if the battery isn't being charged by the gen via the reg/rec then the engine is going to consume battery power until there's nothing left.
If the Neutral light is only glowing when you kick it over it further indicates insufficient power from the charging system to fire the motor and not maintain the battery charge.
If you can take the battery out and charge it, you'll soon know. Start the bike and with it running at tick over,disconnect the battery +ve. If the bike dies, you're not getting anything from the charging system. A bike like the CG125 will run directly from the output of the charging system and the battery is simply for voltage smoothing, periods of high load (lights on) and firing the starter motor.

Edited by Steve Bass on Monday 22 June 22:15

[Prof Prolapse]

Alex@POD said:

The battery is at 13.5 now, but what does it say when you're pressing the starter button? If it's stays the same, it's a bad connection somewhere, if it drops dramatically, the battery is dead.

Reading voltage is not a test for a dead battery.

[Alex@POD]

Prof Prolapse said:

Alex@POD said:

The battery is at 13.5 now, but what does it say when you're pressing the starter button? If it's stays the same, it's a bad connection somewhere, if it drops dramatically, the battery is dead.

Reading voltage is not a test for a dead battery.

It may have been a hasty description, but if you battery shows a decent voltage when disconnected, but down to a few volts when you try to draw current from it, yet it's not powering anything, it's not exactly healthy.

I am talking about a standard vehicle battery in a vehicle application of course, where we know what to expect.

[Matt_E_Mulsion]

A battery cannot show 13.5v at rest. I'd start by working out what is wrong with your meter because false readings aren't going to help at all.

[anonymous-user]

I do think that 125s get more abuse than the larger capacity bikes by the nature of them being used by learners and some owners that probably don't have that much mechanical sympathy. The 2009 YBR I bought to practice on has needed a few bits and bobs doing. I was also considering buying a second hand Chinese bike so am very glad I didn't go down that route!

[TimmyMallett]

I hope he told you about all these problems when he sold it to you.

Or it was free.

[anonymous-user]

TimmyMallett said:

I hope he told you about all these problems when he sold it to you.

Or it was free.

Strange post. I don't think I have ever bought a second had car or bike that doesn't need something doing to it.

[philh88]

Steve Bass said:

Does it do this with the key off and removed???

For it to start on the button and slowly decline in performance to not wanting to is indicative of a battery issue, but i'd expect it to fire up when kicked regardless especially as it's a carb'd motor.

You might find that the reg/rec is faulty. It might have come to you with a full battery for show but if the battery isn't being charged by the gen via the reg/rec then the engine is going to consume battery power until there's nothing left.
If the Neutral light is only glowing when you kick it over it further indicates insufficient power from the charging system to fire the motor and not maintain the battery charge.
If you can take the battery out and charge it, you'll soon know. Start the bike and with it running at tick over,disconnect the battery +ve. If the bike dies, you're not getting anything from the charging system. A bike like the CG125 will run directly from the output of the charging system and the battery is simply for voltage smoothing, periods of high load (lights on) and firing the starter motor.

Edited by Steve Bass on Monday 22 June 22:15

Yes, the N light stayed on if the key was out, so I was leaving it in 1st when switching it off.

I might have to look down the Reg/rec line of enquiry as well. It seems I may have two faults here - as the bike is completely dead now and wont kick over, the damaged ignition wires will hopefully explain that if its no longer making a circuit. ( but also means I can't start the bike to carry out the test with the battery that you've suggested.

The possible second fault could be why I was having problems with the electric start horn, indicators etc not working and causing the engine to cut.

[philh88]

TimmyMallett said:

I hope he told you about all these problems when he sold it to you.

Or it was free.

He told me about the Neutral Light staying on. Otherwise though, he had sent me videos on the day of it all working perfectly, and had been using it daily to get to work, which is where I had it collected from.

It also has just passed its MOT, which means it must have been working reasonably well then. May just be my usual bad luck!

Edited by philh88 on Tuesday 23 June 10:28

[philh88]

Matt_E_Mulsion said:

A battery cannot show 13.5v at rest. I'd start by working out what is wrong with your meter because false readings aren't going to help at all.

That was just after taking it off the charge and I was probably hasty in taking the probes off as the reading was still dropping gradually. It was reading a more normal 12ish a day later.

[mickyh7]

I appreciate you want to sort this yourself, but it will be a doddle for a back street bike shop to sort.
Bread and Butter job really.
Honda 125's had the same problems in the 70's and 80's.
Its easy to fry other stuff if your not careful.
Rectifiers etc. If indeed they are still used?
For quickness and my own mind, I'd throw some money in that direction.
You'll be amazed at whats crammed inside Headlamp !

[philh88]

mickyh7 said:

I appreciate you want to sort this yourself, but it will be a doddle for a back street bike shop to sort.
Bread and Butter job really.
Honda 125's had the same problems in the 70's and 80's.
Its easy to fry other stuff if your not careful.
Rectifiers etc. If indeed they are still used?
For quickness and my own mind, I'd throw some money in that direction.
You'll be amazed at whats crammed inside Headlamp !

I am starting to think that might be the best course of action, especially as i currently have it stored in my conservatory while my workshop is being built!

[mickyh7]

I doubt it will cost much.
Its quite a simple circuit to trace.
Lots of used parts available as well.
Good Luck.
Let us know what it was please?