lead substitute for commandos

I was wondering if this would extend the life of the head and upper cyclinder?




By the way does anybody know of the longest mileage before the rings gave up?

Most lead substitutes are 'snake oil' and not needed in a Commando anyway.

Rign life depends on what you mean by worn out. I have seen a Commando reach 100,000 miles without a teardown but most cast rings are reaching the end of their prime by 30,000 miles. Chrome rings can last 3 times as long. This is with good fuel mixtures and no "accidents".
Rich mixtures or bad timing can cut ring life dramatically. Jim

Main concern on leadless was valve seats wear, so many vendors converted other brands as they came in, but Norton has hard seats and tolerates unleaded fine.
Octane effect is whole 'nother issue. 100,000 miles 100, 000 miles - Ok a possible pie in the sky figure - I've more than one old seasoned Nortoneer mention.
Just not me - yet - if ever.