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:I don't see any fights happening here, seems we are all pretty much on the same page.
Okay.....

This bike is sweet! Remember when people where paying 5K for things like this? Should have got on the bandwagon then.

12060d1423108610-1972-cb350-big-wheel-ebay-bin-7000-image.jpg


Edit......

By the 70s.......for all practical purpose lead in fuels in the US was non existent. This cool machine still exists today!
 

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valve seat recession used to be a common topic on may forums as leaded fuel became less available. It was rarely an issue with valves - just seats and only for machines not designed for unleaded gas. TEL is of course one the earliest and most used knock inhibiting compounds which all gasoline is laced with because it all has a naturally low resistance to detonation (knock). Then it was replaced with nice clean MTBE which turned out to be worse than lead. Alcohol - ethanol and methanol have much higher knock resistance than gasoline and diesel is way up there.
I think that the knock resistance of diesel fuel is pretty low.
 

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I think you are correct.
Probably why they idle with a knock-a-knock-a-knock-a-knock-a

But the nice thing about a diesel engine is that it runs the same all the time ;)
http://www.sbintl.com/tech_library/articles/understanding_valve_design_and_alloys.pdf <- good read
That's a really interesting point. I'm not sure whether the noise is coming from detonation of the fuel/air charge or not. I think that, generally speaking, ignition of the charge, no matter the fuel type, is supposed to occur in a controlled fashion and move smoothly, rather than for the entire charge or a portion of it to react in constant volume. I think that when this happens, pressures can get really high and do serious engine damage. I hope that others will weigh-in on this topic, especially if I am off track.
 

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That's a really interesting point. I'm not sure whether the noise is coming from detonation of the fuel/air charge or not. I think that, generally speaking, ignition of the charge, no matter the fuel type, is supposed to occur in a controlled fashion and move smoothly, rather than for the entire charge or a portion of it to react in constant volume. I think that when this happens, pressures can get really high and do serious engine damage. I hope that others will weigh-in on this topic, especially if I am off track.
I was doing a duel plug conversion about a year ago and got into a discussion with a few eggheads and did some digging on the subject. I know nothing about diesels other than I want a Cummins for my Ramcharger. Anyway... yes definitely want to burn in a controlled fashion. One one of the Honda engines with duel plugs, they even controlled the timing independently on each plug to control the burn. They can use sequential ignition to reduce knocking and improve fuel consumption etc etc. As for noise... in this case, the rapid combustion lead to crank rattle, so had to suppress combustion pressure at some points, I believe by retarding ignition on just one of the plugs. Anyway... just for the record, I'm no expert on this stuff and it tends to make my head hurt. Basically, all I wanted to know was how much I had to bump my timing back because of the duel plug conversion.
 
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