NGK twin electrode have the core in the middle, (you can see it in clear line of sight) and the electrodes curving in towards it. They're meant to burn better, so they don't get so much carbon build up. They don't spark to both electrodes at once, just one but the spark will find the best path, and with more area than a single electrode it has more chance.
All plugs burn out though so you still have to clean regap or replace them.

My Bimota use to eat irridiums they would foul and then fail so quickly I used to have a spare set ready, but with the copper ones it doesn't seem to happen.

Found some goodies in my project i stripped the bike down and found brembo front an rear brake braided hoses and a KnN filter shame that the ar** ho** previous owner put 5Ltrs of oil in a bike that only takes 2.3 and he never attached the air box properly

Sorry to change the subject im gunna put normal plugs in

Ive heard back from the mechanic who was cleaning the carbs and well its good but not so good three of the jets where blocked and the one good one the needle jet bolt had snapped picture to follow does any one know a part number or wer i can get one from

Its the knut on the left

Hollow brass screw; very easy to break now they are so old and brittle.
Ensure the emulsion tube and the jet holder are compressed down onto the o ring properly by hand before tightening; don't use the screw to pull the two parts together ! Don't omit the brass washer.,

Part is same on many models .

1AE145650000

http://www.yamahamotorcyclespares.co.uk ... 0000&uid=0

Your local dealer may get one for you to save p+p.

Some kind soul wth a heap of scrap carbs might post one out to you but most keep these for their own use.They do fracture in service.

chris6409 wrote:Ive heard back from the mechanic who was cleaning the carbs and well its good but not so good three of the jets where blocked and the one good one the needle jet bolt had snapped picture to follow does any one know a part number or wer i can get one from

By Jove,that is hard to read/decipher !
Was it typed on a phone ?
(We don't do text on here; too hard to follow)

I read it ok and kind of knew what he meant. If the part is common to the FZR foxeye then I might have one.

U wd no wat it was abt coz of yor savvy Boris,

Is that what we call a 600R (YZF 600R)? or the later 3HE.
I get told off for not specifing on the US forum and get mixed up.

There is a comprehensive fitment list (extendable) on the linked page from Sutton's.

Good thing about Mikuni's is ; parts like this do not differ slightly, ether they fit or they don't.