Is it mis-firing as well?
First, fit an electronic ignition coil from a newer 'Classic' style engine. Cut both the wires leqading under the flywheel to the existing points and forget about them. Connect the STOP switch wire (one of those you just cut) to the terminal on the new coil. That's it.
If you still have problems (unlikely) you will have to strip the carb - but these ancient carbs usually fail 'no fuel' rather than too much.
If you can't find an alternative coil, I can supply a retro-fit module that will convert your coil to electronic ignition.
phil_saunders@bigfoot.com
Phil Saunders, October 2008
