Really in need of some input on this one

[UpcomingChris]

So i have a CG125, It's been sitting for quite a few months, The other day i tried getting it going and failed, It was not even sparking, so i put it away, Yesterday i went to have another go, and it was sparking, i got it running and took it for a little spin, it was perfect, Today i go down to go and take it for a MOT and again there's not even a spark, I tried bump starting it and it ticked over for about 5 seconds, revved it a few times and then it just died down to nothing, After it almost bumped and did tick over i figured it must be sparking, But when i tested it there was no spark, Absolutely nothing has changed since yesterday and I'm completely confused about what's going on, Any help is greatly appreciated.

It's a Honda CG125, 98 - 00 model, Kick only, nothing fancy on it

[P.]

Have you tried a new spark plug.

Remove the cap which sits on the spark plug, usually unscrews, trim a few mm of the cable off, then screw it back on... needs a little bit of force to do so.

Retry. Would probably give the battery a charge.

[UpcomingChris]

[P.]

[UpcomingChris]

[UpcomingChris]

Im literally at a dead end here. I tried what you suggested. I checked every connection everywhere on the bike I could find, tried different spark plugs and leads / caps. The electrics are perfect. Just no spark. I've tried everything I could possibly think of. I stood there
for ages just looking at it to check if I missed anything. And nothong. Absolutly no sign of a spark. What could cause this to just happen over night? It was running perfectly the day before... I just dont get it.

Could it be tje CDI or whatever it's called?

[andy_uk]

Have you checked the kill switch, in case it's intermittently making/breaking the connection?
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Aprilia Classic 125, GS500E, ER5-A1, ER5-C4, ER6 & an XJ6 project frame...

[UpcomingChris]

[Ichy]

Have you checked the coil connections? fuses? You will need to get a multimeter on it to check for continuity. Only other thing I can think of is a faulty ignition switch or generator.
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https://www.metacafe.com/watch/1972097/how_to_behave_on_a_forum/

[Pete.]

Check for power at the coil when the ignition is on. No power = problem with coil power feed. Power = problem with coil, lead, plug or CDi/pickup.

Make double sure the battery connections are clean and tight.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[UpcomingChris]

[mattsmith95]

Could be the ignition switch....sounds unlikely but I've had a faulty switch a while back.

[UpcomingChris]

[mudcow007]

when i was having issues with the spark on my CG

i took the coil off an tested it on my bench, connecting it direct to a battery an run a wire to the tip of the plug an see if it sparks

if it does, the problem is on the bike an not the coil

[Pete.]

[stevo as b4]

I had a real dumb blonde moment helping my mate try to get his CG125 running after he'd bought it, and done some work.

He ordered a new battery and we spent ages checking the wiring, plug, coil etc etc bump starting and the rest, before realising it was a 6v battery we'd fitted not a 12volt like it had before!

[Bunny Lingus]

Your ignition switch ends in a plastic connector block. Disconnect the block & try & start the bike. You wont have any dash lights & your headlamp may or may not work but the engine should start. You say you have a spare spark plug? With the ignition switch still disconnected connect the plug to the HT lead & make sure the business end is touching the engine block or fins but don't hold it on with your hand unless you like electric shocks. Kick it. You should see fat blueish sparks. If not repeat with the block connected. If still not, unscrew the HT cap & push a nail or screw a screw into the lead & earth that to the motor. Kick it. Examine your coil & make sure the earth (green wire) has not come adrift.
Still no spark? Examine the wires that come out of the left hand side crank case. These are the wires that run from your geny to your CDI. Look for damage to the insulation. Any bare wire making contact? Examine the block connector that the wires go to. Disconnect it & look for melted plastic. If good, spray some WD40 in & around the block & reconnect. Try starting it again.

No good? Examine your CDI block connector & hit that with some WD. There is also a plastic envelope containing a widget, check & spray its block. If you still ain't firing then its time to break out a multimeter & run some tests but concentrate on your ignition switch & main ignition wire 'cos you may have a short. My CG engine is electric start. Is yours? If yes, check the fuse under the left hand panel... Good luck. Ok, just checked... Kick only. Where are you? Maybe someone near you can help by swapping out your coil &/or CDI.
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Bunny Lingus & The Flipside Faggots

[zapmole]

How big is the spark plug gap, I had a problem it's mine recently thinking I had a good gap but turns out it was far too big brought it in a bit sparking perfect now
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Honda CG 125 red 1991

[zapmole]

How big is the spark plug gap, I had a problem it's mine recently thinking I had a good gap but turns out it was far too big brought it in a bit sparking perfect now
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Honda CG 125 red 1991

[UpcomingChris]

[mudcow007]

[Robby]

Alternative idea, water in the carb.

I'm assuming UpcomingChris is a bit of a mechanical noob, so may be making some of the basic mistakes in fault finding. When looking for a spark on a kick-start only bike, you need to be doing it somewhere dark. Whilst we always say you should be looking for a fat, blue spark something like that is likely to only make a weak looking orange spark when you're kicking it over and trying to look at the plug. If you do that in any kind of light, you might not even see it.

If the carb is full of water then it may occasionally run for a few seconds, but mostly just fail. Hold a small container under the carb and open the screw on the bottom of the float bowl. Let it drain for about 20 seconds, then close the screw and inspect the contents of the container. If there is a layer of clear or dirty liquid at the bottom, or some drops that don't mix into the petrol, you have water in there. Now the water is drained out of the carb, try starting it again.

If there is no water, have a good look at your fuses, or just replace them anyway. I don't know if your bike has modern blade fuses, or old style round glass fuses, but I have more than once come across silly problems with poor contacts on old style glass fuses. It looks ok, it works sometimes, but the fuse itself has a poor connection. New fuses fixes the problem cheaply.

Of course, before doing any fault finding, make sure that the battery is fully charged.

[UpcomingChris]

[Bunny Lingus]

https://i24.photobucket.com/albums/c4/bunnylingusandtheflipsidefaggots/20140729_163443_zps33a78f39.jpg

https://i24.photobucket.com/albums/c4/bunnylingusandtheflipsidefaggots/20140729_163506_zps84ad077b.jpg

Ignore the photos for now 'cos I wanna eliminate the ignition switch first...
Ok. Your ignition switch goes to a block connector similar to the ones pictured. Underneath the bit you put your key into is a black wire. Actually that's a lie, beneath the black stuff are four or five wires. One is black, one is red don't worry about the others for now. All these wires go to a white (or black) connector block. You just need to disconnect the block & it pulls into two pieces. One bit goes to the key switch & the other goes to the loom. Inside the block are pins & slots. I can't show you that 'cos mine is hot wired & that is what you're about to do to yours. The block that goes to the loom should be slots. Your mission Jim, should you choose to accept it, is to connect the black wire to the red wire by sticking a short bit of wire - one end into the red slot & the other into the black slot. Your ignition is now hot wired & your neutral light should light up.

Kick your bike over. It should fire up if it was your switch that was faulty. Try that & get back to us. Make sure that it is the black wire you connect to the red wire & not the black & white wire...
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Bunny Lingus & The Flipside Faggots

[UpcomingChris]