Author Topic: Lucas E3LM - Advanced or retard question  (Read 212 times)

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Lucas E3LM - Advanced or retard question
« on: 19 October, 2021, 15:38:58 »

See attachment.

Lucas E3LM magneto off a BSA M33 1955. Magneto rotation is clockwise. Amal Concentric 928 19cc idle, 106 Middle notch and 220 main jet - all advised by Amal for this bike. 20% general jet size when using concentric is their rule of thumb. In general no choke is required.

When slack cable - is this in an advanced position or a retarded position?

When I pull the cable via the lever and it tightens the cable am I advancing or retarding?

I am starting with Level pulled 50% of the way round. It starts first kick.

After warm it still runs faster with cable pulled - is this fully retarded meaning my mixture is too weak?



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Re: Lucas E3LM - Advanced or retard question
« Reply #1 on: 19 October, 2021, 16:56:13 »
When you pull the cable it is advancing the timing. Your cable comes out of the magneto on the right, but on mine (also an M33) it comes out from the left; pulling the cable retards the ignition. I also start with the lever pulled 50% round; like you I'm starting half retarded.

When warm, my bike runs better with the cable slack, and yours should (and does) run better with it tight.