Please excuse the interuption but I've had some good help from here in the past.
My Fake Goldie is refusing to start.
I had her running last weekend, she ran fine for about 15 minutes after not being started for two months (I know). When trying to get her going again after the stall she wasn't interested.
So today, I've changed the petrol and drained the carb, she'll now catch but not keep going. So plug out, and check, there is big blue spark, I have loads of compression but I put a squirt or oil in the bore to see if it was a compression issue (it felt fine but couldn't hurt). The plug is wet and stinks of fuel. After a good twenty kicks I gave in removed the plug and had some lunch. Out again after lunch and still the same, she'll fire but not catch and keep going...
Oh, the petrol tank cap was open during all this, so it's not a vent issue.
I have as spark, I have fuel and I have compression, I should have a working motor but...
I'd strip and clean the carb (or at least the float chamber) and maybe think about fresh fuel. The trouble with aged ethanol fuel is that it's not just consistent. It might be that you're now drawing water through.
I'd go for the easiest thing first and try to replace the sparkplug. (Even if you have an old one lie around)
Sometimes a spark plug can perform OK outside, under regular atmospheric pressure, but short- circuit under compression.
A wet plug and dead engine is a good indication of one of the 2:
Either a very very rich mixture, more than can the engine can start with ("Overflow")
or a plug which do not fire in the barrel, although does out of barrel.
If this is the case, It would usually start on first kick after changing the spark plug.
Rik is correct drain the float chamber as it will have separated by now, modern fuel is designed purely for use Iin modern injection type motors where fuel sits in closed fuel systems and controlled vented tanks - because of this it stays "fresh" for longer periods.
Anything with a carb or crude vent system like our bikes will suffer
Spark plugs will often creat good spark outside the combustion chamber, but when under compression can break down - so another plug is a quick and easy check
