New Leaded Fuel

[Rob Harknett]

New_leaded_fuel.pdf

Don't get too excited, the new leaded fuel refers to its introduction during the war. We are now trying to overcome problems of non leaded fuel. Seems like owners of prewar machines need not bother. They were happily running on unleaded fuel when they were new. All be it of a much lower octane rating.

[Bogwheel]

I remember reading that in the Triumph OC (Cars) magazine some years ago. They'd done some practical research on, I think, a Herald. There were no ill effects, so I've never bothered with additives. So far, so good.

[Rob Harknett]

I always assumed petrol had lead in it. Octane was lower years ago, I believe up to about 76 octane by mid / late 30's. It appears lead was not added until early 40's wartime. Perhaps to improve octane rating and get as much mileage as possible from what little fuel we had. As engine design did not change much until the alloy head arrived, our bikes until then did not need leaded petrol or an additive. Except perhaps a couple of shots of Redex upper cylinder lubricant in the petrol occasionally. It has been stated, very little lead is needed. A dirty engine that used leaded petrol, will stay lead friendly for some time, without any ill effect.

[Andy51]

I did considerable research on leaded fuel, using among other sources a UN report, for a Jampot article published a few years ago. There has been a lot of scaremongering on unleaded fuel but unless you do a lot of mileage at over 4,000 rpm it makes very little difference at all - so if you don't regularly exceed 70+ mph for long distances (less for the lightweights?!), don't worry about it! Andy