CG125 not firing

[Tamsin]

Right, so some of you will know the saga of the blown up CG Engine.

Its a 2001 M1 Model which should have electric and kick start however the temporary replacement engine I have found is a kick start only CDI motor. Engine is in situ and wired up but she just isn't starting.

Nice strong spark and it smells like fuel is getting through but how do you check that? There is definitely compression too

Any suggestions to get her going?

[RhynoCZ]

Have you checked the air filter?
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[bypass2]

How old is the petrol.

[Tamsin]

Petrol is about 5 weeks old, air filter is absolutely a-ok fine

[RhynoCZ]

[bypass2]

Are you useing your carb. or did a carb come with the replacement engine ifso maybe new carb needs cleaning. or just needs a bit of time to get started.

[Tamsin]

same carb as before, but taken apart, stripped and cleaned.

the old engine ran happily on fuel twice as old

[Efes123]

Not been on much recently, so don't know the saga

When you say not starting, do you mean not turning over or not firing?

If you have a strong spark, then it should try to fire up. The smell of fuel will be from the carbs I suspect. If you can smell it from the plugs then the plug isn't sparking and the plug will be wet with fuel.
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Honda Goldwing GL 1000 Current love
Honda VT500 ED - SOLD
Projects Suzuki GS125 Done, then stolen - Kawasaki GPX750R SOLD - Honda VF750S SOLD

[RhynoCZ]

Have you tried to bump start it? The battery might be flat.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[Tamsin]

Would the battery really make that difference on a kickstart? battery is a-ok though, nice and strong.

plug was sparking and smells of fuel.

[bypass2]

Try a new plug

[stuartt]

Have you checked every electrical connection is ok ?

[RhynoCZ]

[Rogerborg]

[blurredman]

[Tamsin]

[P.]

Try and get it running again, check the plug for wetness. If its dry you aren't getting fuel.

Trim HT lead a few mm and re-attach the plug cap also, might as well while you are down there.

[Tamsin]

[Tamsin]

[RhynoCZ]

The last thing, I could think of, would be the valve clearances.

If, taking the old fuel is a myth and the CG does not need the battery.
(My zxr won't start with 5-6 weeks old fuel in it, the GPz I had was the same and my mates FMX is also the same. Oddly enough, my mates 919 RR starts with anything in the tank even with lower voltage on the battery.)

Why valve clearances? Well, the GPz I had ran on 3 cylinders, shortly after I got it. I had strong spark on all four plugs, got the mixture in each cylinder, carbs were balanced and still going on 3 cylinders. I gave the bike to a mechanic, because I didn't know better back then, he set the valve clearances and it ran on 4 cylinders with no hesitation.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[Tamsin]

I did wonder about that too. Didn't have my feeler gauge with me, for an engine that was sold as working I didnt think I'd need to dig them out...

[blurredman]

CG's are 3 thou on both inhale and exhale stroke valves. It is quite a large gap.
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CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S.
Current: 1973 MZ ES250/2 - 17k. , 1979 Suzuki TS185ER - 9k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 38k, 1989 MZ ETZ251 - 49k

[Tamsin]

Valves were a little off but certainly not bad, all nicely gapped now though. Tried fresh fuel, new sparked and trimmed the ht lead and still no sign at all of wanting to start. Got a friend coming to have a look to see of she can suss it...

[Kickstart]

Hi

Given it is a different model of CG125 engine, is the ignition system all compatible? Assuming you are using you old cdi unit, etc, with the new engine and flywheel?

If not possible that the timing is WAY out.

Might be worth using a strobe light on it to check the timing.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Tamsin]

I don't have a strobe light unfortunately, its a CDI engine so should all be compatible one hopes