Oldbeek: my experience with gasoline engines, backfiring back thru the carb is too lean of fuel mixture 90+% of the time....double check you have proper flow supply to carb...and carb passages are clean etc...

-if timing is overly advanced, starting will be difficult, engine unresponsive and generally not happy, of course, the spark is igniting the fuel mixture too soon...
-if timing is too late, engine will be sluggish as well, and the exhaust system tends to be very hot, as the fire is lit too late and is still burning in the manifold, muffler etc....
-have a close look at the plugs, they tell a story if you read them..

Good thought. The heat manifold is getting hotter than usual. Everything was running perfect before the Mag died. I am pretty sure I have it timed late. Thanks

-another good check if exhaust system is running overly hot is to make sure the muffler is not plugged or partially plugged
-internal combustion engines do not like to be restricted intake or exhaust, engine output will suffer dramatically

Hi OB,
if you set the pony flywheel timing marks as per your OMI for re-fitting the mag. the "M" timing marks for the Mag drive gear and the Big drive gear, in the timing case, should be visible if you are on the correct pony rear/left cylinder compression stroke at TDC No1 as viewed when facing from the main engine flywheel housing towards the radiator.
You should be able to see if the "M" marks are aligned or not--seems on later units the circlip that held the slotted mag drive gear to its shaft were omitted and this is a common issue of loosing the timing.
Having the mag points gap set to between 0.014" and 0.018" and said timing  "M's" aligned you should be good to go.
Cheers,
Eddie B.

ERB, Thanks I cold not see the timing marks. I advanced it one gear tooth. Ran better but still not as good. Advanced it another gear tooth and it is back to its old self. I knew the rotor was not pointing right when I advanced the gear the first time. Just did not think it could run being two teeth off. If I had painted a good white timing mark on the damper when I built it would have helped.

great news OB, i was wondering what happened..2 teeth off no wonder it was so sickly...must of been hard starting as well..
-like they say, timing is everything

just for future reference you can use a inductive pickup timing light on a magneto ignition. you only need a 12v battery to power the light the pick is clips on to the plug lead as normal.


a mag that is sad can be rectified by a proper cleaning of the base and the addition of a rubbing of 2B graphite pencil to the mounting faces the electrical items rely on a good conductive path. for a mag that path goes through the body of the engine and the mag. im prove it and your mag will work fine in a lot of cases. also mags need to be tested when aswell as cold as heat changes resistance and a mag that works when cold may not work when hot and vice versa. the gas or electric oven is handy for this just dont get caught using her oven for these projects. a freind of dads got cuaght once and we didnt see him for some time.