Nigsey, you say you are on a BTH mag. If mag, 30 thou is too wide a gap on the plugs I'd have thought. Be careful with NGKs, they are widely forged by unscrupulous manufacturers. I'd stick with Champions. If you are still on mag, you don't want plugs with an R in the name (=Resistor), nor do you want resistors in the caps. Are you getting any leaking from the carbs? I think you are also not giving it enough fist. I warm mine up for the first 12 miles, but quite often this is at 70mph on a dual carriageway and I'm still running my engine in with new pistons and rings (and bottom end, but that's another story). Bear in mind that in top, 100mph is only about 3500 revs. The other thing I would try is removing the Vokes filters and revert to standard settings on jets etc and see what this does.
Dave, strangely, if my plugs soot up it's usually the other way round the front (no 2) is sooty. I do use quite a lot of choke (up until end of the road). I'm on 32mm Amal Mk1 Concentrics though.
Dave, strangely, if my plugs soot up it's usually the other way round the front (no 2) is sooty. I do use quite a lot of choke (up until end of the road). I'm on 32mm Amal Mk1 Concentrics though.
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