Starting Problems

My bikes recently started having problems starting ....she has always started first or second kick since owning her....yesterday took her for MOT and she wouldn't start...eventually she did and then started first kick on leaving MOT place after about a 50 minute wait.....valves perfect, new plug not much else to check ? popped out slow idle jet and main jet all clean as a whistle ?...baffled ?

Old age Mauser, old age....
Let's face it, all our bikes are approaching 'antique' status, and later if not sooner they'll throw in the towel.
It's basically used up, and redoing the entire lot is, of course, beyond the possibilities
So, clean the bugger, crate it and send it down to me, I'll look after the poor old thing here

Or, clean the tank and renew the petrol filter?