Trouble starting my CG125

[JH]

The last couple of days, I've had a problem getting my CG125 to start.

It's an older model (from 1999/2000), with only the kick-start, and the three-position choke.

The symptoms are that when you kick it over from cold, it will start ticking over, but is very, very sluggish, and then just bogs down and dies after a few seconds. This is with the choke off, and no throttle.

If you attempt to give it any throttle whilst it is ticking like this, it dies immediately.

If you give it any throttle or choke before kicking over, it won't kick over at all.

I've not had the spark plug out yet to check that, but it was a new Denso plug that was put in around 600 miles ago.

I did manage to get it started eventually after some tinkering, but I'm looking for some opinions and thoughts as to what the cause was to make sure I'm thinking along the right lines.

Cheers,


JH
____________________
Honda CG125-W
CBT: 7 Aug 2010

[pepperami]

Drop the float bowl on the carb and see if there are any nasties in there?
Has the needle come loose?

Not all new plugs are good, you may have a duffer! put the old one back in and see if that makes any difference?
Plug cap ?

this is what i would be looking at
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I am the sum total of my own existence, what went before makes me who I am now!

[JH]

I should say that I'd already suspected this bike of running rich, and was planning on doing some fiddling with it this weekend after doing the sprockets and chain (which should arrive today), and checking/setting the valve clearances.

My tactic this morning was to fiddle with the idle screw on the carb (it's the knurled screw just next to the float bowl that I adjusted). Gave this a quarter turn in, kicked it over, tested, then rinse and repeat until I'd adjusted the thing a total of 1.25 turns inwards. The first quarter turn inwards, the screw was quite firmly seated, and needed a slight amount of pressure to 'crack' it and get it moving, so I don't think it's worked loose.

Once adjusted in this way, the engine would tick over, and allow me to use the throttle to get it warmed up a bit before setting off.

I know it's not recommended to fiddle with carb settings whilst the engine is cold, but it's the only way I could think of getting the engine running and get to work. I kept a small toolkit with me for on-the-road maintenance in case anything ontoward happened, but all seems well, and if anything the bike is idling much better than it has since I got it.

So, next steps?

- Bung some RedEx in and see how it goes?
- Float bowl off and given a quick clean?
- Carb off, strip and rebuild?

Cheers,


JH
____________________
Honda CG125-W
CBT: 7 Aug 2010

[stonesie]

I know with mine the cold start ritual is, twist the throttle to full and back to idle then with no choke 1 kick and she's away as long as I hoof it, a namby pamby kick doesn't always work.
(Note, mine has the accelerator pump carb)

Once it is warm have a fiddle with that screw, get it to its maximum revs then open it a touch, mine ended up less than one turn open but the engine starts and idles nicely and doesn't cut out at the lights like it used to.


Regarding spark plugs, NGK all the way.


I really sympathise with you, after stripping and cleaning my carb it took half an hour of entertainment on the kick start to get the sod running

[N cee thirty]

mine did the same the other night,really annoying

toke off the air filter,still no good

drained carb,nothing

changed the plug and finally fired :S
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'00 Aprilia RS50 > '92 Honda CG > '99 Yamaha Fazer > '91 Yamaha RXS > '79 Suzuki X5 > 01' Honda Cg > 07' Honda Cg > 82' Kawasaki Z200 > suzuki gsxr 400 gk73a > honda vfr 400 NC30 Mod 2 Passed 09/06/2011

Jewlio Iglesias wrote: I actually did vote BNP once

[JH]

Resurrecting the thread, because the problem is back...

Yesterday, went to start the bike from cold in the morning, but it was having none of it at all. Same as before- zero choke, zero throttle or it wouldn't turn over at all. When it did kick over, it would go for maybe two or three turns of the engine, and then die.

So, I called the AA out, and their guy unscewed the pilot screw a little, and the bike sprung to life. Got about a quarter mile away from home, stopped at some traffic lights, and the bike died on me - the pilot screw had vibrated loose :s

Second call into AA, and their guy (who was a biker this time) gave me a temporary fix to get back round the road to the house, and gave me a few contacts for breakers yards to pick up a new pilot screw.

Once I got the new pilot screw in, managed to get the bike started up, and took it for a quick run to get the engine warmed up before adjusting the pilot so that everything seemed OK. Adjusted the idle speed to suit at the same time. Stopped and started a few times to make sure it would fire up, and it all seemed fine.

This morning, go to start the bike, and it's the same problems as above again

Gave the battery a boost (although that shouldn't affect the start). The bullet connectors were a bit wet in their little plastic boots, so WD40 and a dry out on those. Battery still seems a bit low, so will give an overnight trickle charge tonight to get it back where it should be.

Checked the air box, and the filter seemed OK (two-part foam filter. Outer course foam was dry, inner was OK too).

Checked the spark, and got a good clean spark. Changed the plug just to be safe, but same issue.

Kicked it over a few times, and plug ended up fouled with petrol, so I know it was getting fuel that far. Cleaned plug and let it dry out before popping back in.

In the end, the AA guy that I had this morning put the pilot a further half turn out, and that got the bike into life.

So still looking for more possibilities on what to check, and where the real problem lies.
____________________
Honda CG125-W
CBT: 7 Aug 2010

[cb1rocket]

your carb needs to be set up properly, probably needing a proper clean!