what plugs

[townsends20]

Hi Guy's
    this bike gets better as I am getting these things sorted out. I need to know the best plugs to use I am using ngk's bpr6es-11 as I seem to have a stock of these and the bike is going fine on these although I am still running in, it is on a competition mag I don't know if that makes a difference here is a few pics. of the bike so far.     

[chaterlea25]

Hi townsends20,
Plugs with "R" in the code are resistor types,
these are not really suitable for magneto ignition
Plain old B6's or 7's or if you want ES's (long nose)

others swear by or at these or champions

HTH
John O R

[mike667]

thats a beauty!

[muskrat]

That's one beautiful bike mate. I love those tanks. Not sure I could ride with the bars that way, I'd need to flip'em over to slope down a bit.
NGK B7 or 8ES is my choice.
Cheers

[bsa-bill]

If it's not getting pre-ignition when up to running temp then use BP6ES but ditch the BPR6ES, seems to be pretty universal that they don't do Maggies much good as John states.
my Maggie is (was) suspect so I've been dabbling with plugs and found  Bosch thin wire platinum to provide a better spark for starting than Champion Ns or NGK BPs however both these marks also make thin wire plugs so maybe I'm being a bit unfair

[townsends20]

Hi Muskrat / Bill & all
       It  seems to to be a matter of choice as to what plugs to use,( except  resistor type) the main thing for me is not to hole the pistons or burn out the valves with 10.5 to1 pistons what would be the safest plugs to use?
           On another note I am going to downturn the bars later when I get more comfortable, it started out with clip-on with an alloy headstock, then I  went to ace bars and that's before I even got on it! Then I said to myself who are you trying to kid. Yes I ain't getting any younger you know what I mean. And don't forget its been 35+ years for me and the bike.
   All the best Steve. 

[bsa-bill]

never mind the bike Steve, that is one mean looking trolley

As for plugs (remembering apart from providing a spark a plugs main job is to transfer heat from combustion chamber to head and thence to the atmosphere) best to start with a cold plug and work up if they foul, even at today's prices plugs are not too expensive, especially the ones for our old bikes.

Should I admit that I recall plugs stuck at 3 shillings and six pence for what seemed decades

[duTch]

no