Hmm-keep in mind, back when these bikes were built, gasoline octane available was much lower than today.
For instance, in the "National Motor-Gasoline Survey Summer 1952", by the US Dept of the Interior, Bureau of Mines, average octane ratings for "regular" were right around 80 (R+M/2), while Premium grades averaged 85.7.
I run 87 octane in my '52 FL. I've never noticed any pinging. And I tune by the book.
Works for me, I am not claiming anybody else is wrong about their bike.
If anyone wants a copy of the "National Motor-Gasoline Survey", PM me.
Auto advance timer ??
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Excalibur
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Re: Auto advance timer ??
awander
Well, that's an interesting one. It appears to go against the information I'd found when I studied the subject a couple of years ago.
Quote: in 1946 following World War II, gasoline octanes in the United States averaged at 79 for regular and 85 for premium and those numbers climbed year after year until 1954, when premium gasolines were rated as high as 94 octane and regular at 86.
Quote: By 1958, oil companies generally took a position concerning the number of gasoline grades offered with the greatest majority choosing to stick to just two (regular and premium) and simply increasing the octane ratings of both grades of gas with the premium fuels coming very close in octane to the super-premiums offered by some competitors. That year, regular gas averaged at about 90 octane and premium hit the 98-99 mark
http://www.stevesnovasite.com/forums/sh ... p?t=164646
I recall there being 3 or 4 ways to measure gasoline octane (as if the subject isn't confusing enough It could explain some of the discrepancy).
I suspect your 87 octane is the same as my 91. Your '52 came out with 7:1 compression https://justpanhead.com/modelsspecs/52-models/
This being the case, I can see why it's working for you. Great that it is, by the way.
Well, that's an interesting one. It appears to go against the information I'd found when I studied the subject a couple of years ago.
Quote: in 1946 following World War II, gasoline octanes in the United States averaged at 79 for regular and 85 for premium and those numbers climbed year after year until 1954, when premium gasolines were rated as high as 94 octane and regular at 86.
Quote: By 1958, oil companies generally took a position concerning the number of gasoline grades offered with the greatest majority choosing to stick to just two (regular and premium) and simply increasing the octane ratings of both grades of gas with the premium fuels coming very close in octane to the super-premiums offered by some competitors. That year, regular gas averaged at about 90 octane and premium hit the 98-99 mark
http://www.stevesnovasite.com/forums/sh ... p?t=164646
I recall there being 3 or 4 ways to measure gasoline octane (as if the subject isn't confusing enough It could explain some of the discrepancy).
I suspect your 87 octane is the same as my 91. Your '52 came out with 7:1 compression https://justpanhead.com/modelsspecs/52-models/
This being the case, I can see why it's working for you. Great that it is, by the way.