Spark Plugs - What type to use?

[diebythereaper]

Thanks mate,
Only in from the shed now, what we did was to bend a welding rod and use it and a marker to measure the thread depth for the spark plugs in the head by inserting it into the plug hole and hook the bend in the rod under the threads and then place the hooked end on top of the threads and mark the rod with the permanent marker. It worked a treat!! Same measure as the thread length on the CR9EK's

Just to be double sure, we removed all the short type spark plugs and put in one CR9EK and turned the engine over with fingers crossed... No probs so fitted the CR9EK's and my mate took the bike for a quick spin - about 5 or 6 miles. He said it now pulls through the revs in top gear wheras it wouldnt do it before and he was delighted!!

I checked plugs one and four but there wasnt enough miles on the plugs to colour check them, the bike bike is also a little sluggish below 3k. My mate is going to take the bike for a longer spin tomorrow or the day after.

The C7HSA's plugs were all white so that's why I went for the colder 9's. If the new 9's are still white, should we just raise the needles a notch?? They are set in the middle at the moment cos we checked.

Also what aftermarket coils can we get to improve on the standard ones?? I have dyna green coils in my bike (3 ohm) but dont want to chance them on my mates and blow the cdi or something.

[Variablevalves suck]

Im sure all the 4's run 3ohm but ran some dyna on my B4 with no difference to the power.
Should go up on the mains if its white, lifting the needles will only work if they are low enough to affect WOT. Id change the o'rings first as they are sods for messing the carbs up. If you know they are good then it will be good to mess with the jets/needles.

[diebythereaper]

Thanks VVS, I have the 3 ohm on my GK73 but wouldnt do it to my mates bike without double checking cos dont want to do it damage. I have had a few 1100's as well over the last ten years and always find that the dynas make starting easier and the bike feels better on throttle response and picks up better. Ill get some for the GK76.

As for the carbs: I dunno, from what ive read if it aint broken dont fix it!! But if the plugs remain white we'll have to do something, how could Orings be making the bike run lean???

[Variablevalves suck]

Ye the dyna's should work better, think they do a mini set now that are much easier to fit in under the tank.
Im sure on ther own the o'rings wont make the bike run lean, but something is and if they are bad then altering other things will not give the desired results. Something is out/altered as they aint weak from the factory. Is the rest of the bike standard?

[diebythereaper]

Yep as far as I can see everything else is standard including the exhaust and the bike is not loud or anything.

[Variablevalves suck]

I would think some body has messed with the bike and so id take a look at the carbs to see if they are as OE.