Stepsons scooter would not start today. Well, last night to be honest, he said it has been getting worse.

Only a 50cc, seen bigger lawnmower engines. Anyway I get the job of ‘having a look at it’

Well, from the smell you could tell that petrol was getting through, that leaves the spark. Problem is that it is a Scooter and therefore the engine is shrouded in plastic panels with just a couple of access panels than can be removed, enough to get my hand in.
Took me over an hour, pulled the lead off and checked it that way, Spark so need to get the plug out good job I have skinny arms and hands, Had To work blind.

Plug cleaner than expected, good spark so cleaned and put back in, what a pain.
So we have fuel and spark, still not starting. Eventually got it started but would not rev freely.
Removed air filter, expecting it to be totally clogged up, not bad so not blocked. Anyway eventually got it started, jumped it of the new Gallant battery that is not yet fitted. Now seems to be starting OK, washed the foam filter and will put it back on in the morning. Could I have missed something, air filter not blocked, though was a bit greasy, so a bit of a worry, have I actually fixed the problem. :-/
4 stroke engine.

Any thoughts???