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Retarding ignition to prevent knocking.

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Stevex:
The bike in question is a LM2 with a standard ignition system.
Last summer I noticed that grabbing a handful of throttle at around mid rpm would induce knocking, especially in higher gears.
Since then the bike's been fitted with a lightened flywheel and I've reset the points gaps and set the static ignition to 8°.
Full advance on the 850 Le Mans is 34°, but would it be advisable to maybe set this to 32° in the hope of eliminating the knocking?
Would I actually notice any difference in power delivery by retarding by 2°, not that it matters because I have to back off the throttle every time I hear the engine knocking?
I had a thought that maybe I was running regular fuel (95 octane in UK) instead of premium (97 octane); if so, would the almost 2% increase in octane rating make that much difference?
The bike was also running with a standard exhaust, not sure if this would have any effect, but I'm in the process of replacing the end cans with some slightly modified Lafranconi Competitione items.

twhitaker:

--- Quote ---would the almost 2% increase in octane rating make that much difference?
--- End quote ---

Yes.

Antietam Classic Cycle:
Have you ever replaced the advance weight springs? Could be they're stretched and letting too much advance, too soon.

Vasco DG:
My first thought too. Also has the distributor been swapped at any point? If it's got one out of a small valver in it then it will have different springs that give less overall advance but it is achieved earlier.

Pete

Daniel Kalal:
I found with my Cal2 that a Guzzi centrifugal ignition advance mechanism can go years--perhaps even decades--without new lubrication; but, eventually...

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