CG Won't Start

[Ingah]

Have spent another afternoon with the CG doing slow and time-consuming work required to get it roadworthy again.

And have come across a problem.

Have charged the battery and also checked the voltage with a multimeter (it was 12.7V). It's now down to 12.0V having spent a lot of time trying to start the bike and failing.

The bike has both electric and kick start (it's a 2002 model), and neither is able to start the bike. With the electric start (when it doesn't just "click" and do nothing else, which is an intermittent problem the bike already had before i laid it up 18 months ago), the engine turns over. It does sound weaker than i remember (despite the battery seeming OK), but it won't fire up. No matter what setting i put the choke on.

It's the same with the kick start, the engine makes the turning noise, but doesn't fire up (again irrespective of choke).

I did change the spark plug about 12 months ago (6 months into it being laid up) and as it hasn't been used since i would like to assume it's still OK.

So err... anyone know what i should try/what it could be? (bearing in mind i'd prefer to spend time checking things, than money replacing things).

[rennie]

is the plug sparking?

is the fuel fresh? it goes off!

if 2 yes's take plug out put drop of petrol in cylinder

put plug back in and try to kick.

forget electric start until you've got it going

[Ingah]

is the plug sparking?

Yes, it doesn't look very big, but then i don't know how big it's supposed to be.

is the fuel fresh? it goes off!

Yes, poured out the old stuff and replaced it down the petrol station before starting.

if 2 yes's take plug out put drop of petrol in cylinder

put plug back in and try to kick.

Ah, that was a reaction, it sort of revved for a second as though it was going (suspect that was the petrol dropped in the hole igniting, but that was it, died straight away and same as before. Does this mean that petrol isn't getting into the engine (meaning the problem is somewhere between the fuel pipe (as i know the fuel tap itself works) and engine block (so probably a carburettor issue?)

forget electric start until you've got it going

[rennie]

well, it's either weak spark or fuel not getting through.

I'd say fuel.

is air filter clean?

[eastanglianbiker]

soun ds like you need to remove the carb and clean the jets out inside the float chamber when refitting the slide into the top of the carb make sure you fit it the right way round there is a groove in the slide and if you look into top of carb you will see a small pin sticking out the groove in the slide has to meet that or it will hold throttle fully open

[rennie]

yep! probably caused by gone off fuel!

it goes all sticky and horrible!

[supersapien]

yep! probably caused by gone off fuel!

it goes all sticky and horrible!

 

oh god,don't it just. like boat varnish

did you have the petrol tap turned off when you left it to stand? if not, clean ya carb like everyone is saying and check ya fuel filter

[Lumor_uk]

When you next leave to stand turn tap off and ride to the shops and back till the engine dies.

[Ingah]

Have taken the carb off the bike, then apart, then blew through things like the main jet (which may or may not have been partially blocked, i wasn't too sure, but it's definitely not blocked now!), then sprayed with carb cleaner and also compressed air (separately).

There was some varnish (thickish petrol, still flowed a little bit though) in the float bowl, and in the carb generally, but not all that much and i'm not sure it was the real cause of the problem. It's gone now, of course.

I suspect that me having re-fitted the float needle upside down when i last took the carb apart (haven't used the bike since) was the real issue.

Question: On the bottom of the float bowl is another miniture bowl with something that looks like a diaphragm and needle. They're attached together though, the "needle" doesn't look removable. There is wear apparent to the top of this "needle" though and as i can't see what it is in the Haynes i'm not sure whether it needs replacing or not. NB: I'm not talking about the float needle as that's in the large chamber above.

Float needle.

[eastanglianbiker]

not had cg carb apart for years can you put pic up of the bit u mean??

[rennie]

well you've lost me now!

just put it back together and see if it goes FFS

[Lumor_uk]

I know the bit you mean but it wouldn't stop the bike running, if it was worn fuel would leak out of it when you twist the throttle. It squirts extra fuel into the carb giving the bike a bit of umph when accelerating.

[Ingah]

Having re-fitted the carburettors, it now runs. Ish: http://www.themotorbikeforum.co.uk/view ... p?p=578450

It smoked a hell of a lot at first though (really stunk the house out as i'd left the nearby back door open). So it definitely wasn't just WD40 burning off.

Ah well, progress