LM 1 Timing Issue!

Bike not been run for six months or so. On trying to start, engine just pops and spits. Timing? Thought I.
Bike still has distributor and points. I used the buzzer on my multimeter to check the points opening. Right hand cylinder checked out ok, slight adjustment done.
Left hand cylinder is strange. Buzzer is buzzing continuously, on full rotation of engine, points open or shut.
Not sure what is wrong to make it do that?
It’s been a while since I have had to play with points, etc.

Check the condenser and the state of the condenser wiring. I assume you’ve checked the point faces and gaps.

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Thanks for the suggestion. Yes, checked, cleaned and gapped points first.

you can also check the points are not earthing to the base plate on that side

Brian has a sensible suggestion. It is not unknown for points to short to earth, for example where the insulator passes thru’ the distributor casing. I had an insulator which became mis-shapen and intermittently allowed contact of the terminal-screw to the casing. Took a while to find it, but symptom was as you describe, continuity to earth regardless of point closed or open (battery disconnected etc. for checking).

Thanks Giles, I had been thinking that too. I will check it when it’s not so cold in my garage.

Whilst it could be a failure of the points insulation, my guess would be a shorted condenser, or the insulation on the wire from the points has worn through on an edge of the hole, through the dissy body, for example.

Might be worth disconnecting the coil, and using the meter on ohms just to confirm the points / condenser are ok, and the fault’s not upstream somewhere.