I've got a few questions regarding spark plugs!

[GaZBur]

So can I butt in here and ask a sparkplug related question. I have a twin spark DR650 which gets mamby pamby use weekly on the way to work at 50k and in the weekend gets its neck wrung at Motards or whatever competition is running. At 12,000 k the plugs are all black and sooty around the thread but the contact? gap is clean.
Is it rich (jetted) or is that normal carbon build up. I replaced them anyway.

[avgas]

At 12,000 k the plugs are all black and sooty around the thread but the contact? gap is clean.
Is it rich (jetted) or is that normal carbon build up. I replaced them anyway.

Is the plug seating properly, as i have had a lawn mower with similar issues turned out that a plug had been over tightened at some point and done wonders to the thread.

[koba]

Not even in the RG150's? as i noticed a huge smooth power delivery on mine with iridiums.
Also ment i could run avgas on it with no issues.

Compared to a fresh normal plug I couldn't tell the difference but stayed good untill It blew up!

[koba]

So can I butt in here and ask a sparkplug related question. I have a twin spark DR650 which gets mamby pamby use weekly on the way to work at 50k and in the weekend gets its neck wrung at Motards or whatever competition is running. At 12,000 k the plugs are all black and sooty around the thread but the contact? gap is clean.
Is it rich (jetted) or is that normal carbon build up. I replaced them anyway.

Should have a light soot and cleanish tan area around electrode. google some images to see. Shouldn't have soot on the actual thread if that is what you mean, wrong (too long) plug?

[motorbyclist]

i find the fuel you use has a role to play

did an experiment a while back with 400 and 426cc motorcross bikes and sparkplug life. bp98 gave longest life, gull was ok, shell was fouling up plugs in under 3 hours

Motorcycles don't have a distributor. The pick-up that sends the signal to fire the plug each time the crank turns 360 degrees isn't clever enough to know which TDC stroke it is on.

you sure on that one? the bike has to have some way of timing the spark, and that depends on the bike.

on the old XRs for example, the pickup was attached to the cam shaft, so always fired at the correct TDC (well slightly before of course)

and with all the electronic controls nowadays the spark is meant to be at the right time every time.

[GaZBur]

Should have a light soot and cleanish tan area around electrode. google some images to see. Shouldn't have soot on the actual thread if that is what you mean, wrong (too long) plug?

Is the plug seating properly, as i have had a lawn mower with similar issues turned out that a plug had been over tightened at some point and done wonders to the thread.

I mislead with my original statement. The rim of the plug where the thread ends is black, the threads themselves are clean. The Electrode is also quite clean but slightly brown coloured - so thanks for advice as that sounds normal then. I will look up google for pics - sorry thats what I should have done in the first place instead of hijacking the thread!

[huck farley]

22000 on a 1050 - that must have been through at least 3 triumph dealer services by now, didn't they change the plugs then?

I don't know but a the 10k they took them out and cleaned them. At the 20K they did the same. I see reading through the service checks, they say to replace the spark plugs at 40k Can't complain at that I guess aye? So I guess I have the awnser to my Q now. Thanks all that contributed to the thread.
cheers
Huck

[Max Preload]

A lot of cars (actually most these days) don' have distributors either but the crank still only fires each cylinder in turn on the firing stroke only.

But they have cam angle sensors to tell it which cylinder is firing TDC.

[avgas]

Compared to a fresh normal plug I couldn't tell the difference but stayed good untill It blew up!

I know the feeling.
I lost mine at 24,000k's
God damn cheap oil pumps