I commute 850 k's a week using a standard A14. Under load or acceleration the motor is running perfectly and still revs to 7000 if I'm feeling anti-social. At constant speeds e.g 60 kph or 110 kph I have started getting an intermittent missing fluttery sort of hesitation - it's just enough to notice. My fuel economy has dropped as well. Points, plugs, filter, timing, leads and carb are fine. Anyone experienced this or have any ideas?
Thanks all.

I had similar problem as this once. It was a jet in the carby I think. Anyways, after rinsing out the carburetor and spraying cleaner through all the passageways it worked fine once again.

yer,i also had a similar problem,it was dirt in the idle curcuit.unfortuneately,to clear it out meant taking the carby off,& back flushing with carby cleaner from the bottom.this would usually last a couple of months.