What is your prefered brand of spark plug?

[Scott58]

I've been using NGK for the past year and they seem to work pretty well.

[scan]

Me too on the NGK, but it was what was installed at first and I have just gone with what seemed to work well.

[poppygene]

Never had a problem with NGKs. Well,... I once had an old Yamaha 2-stroke that would foul one on occasion, but that really wasn't the plug's fault.

[Noel]

I been sitting here from 1 am to 4 am on the internet researching spark plugs and the reading of spark plugs. I've never pulled a spark plug and can't because my bikes in the shop for threee weeks waiting for Japan to get it's arse moving with a part that I need.
Anyway here's a good spark reading page although I've found lots of different opinions on every spark page I came across.
http://www.strappe.com/plugs.html

To adhere to the etiquette of the subject's purpose(remember for me it's 4 am in the morning 4.30am NOW) ......
I use stock plugs

although I have a sneaking suspition that when I go the shop to buy a new spark plug, they wont have an exact stock spark plug and I'll have to choose a similar plug that works for my bike AND I will run into problems. That link above is good at explaining heat range markings on plugs and comparison charts and stuff.......which I will probably RE-read after I visit my local shop for some new plugs.(which will be used only for spark plug chops- so I can read the air fuel mixture form the jets)

[Skier]

While I haven't had to change the plugs on my bike yet, my cars don't seem to mind whatever I throw at them. But it does make me feel better to use NGKs over cheapies like Autolites.

[Ladymx]

NGK all the way for me

[ronboskz650sr]

Just NGK. Tried Champion, bike spit them out (not really). Just NGK.

[oldnslo]

I think NGK is OE on most Japanese bikes, and they work great. I would avoid any American brand, generally speaking. Some 25 years ago, when I was in the spark plug biz, Nippondenso was considered superior to NGK, but that was then, don't know about now. ND is still huge in the building of electronic bike components, and I would gladly use them if the local store stocked them. ND is listed as the alternate in the Yamaha factory shop manual.

[BuzZz]

Anything BUT a Champion!!! 2 wires jammed into the spark plug hole are better than the best plug Champion ever made. NGK are good, however about 4 months ago, they had some production problems and some of thier current stock is less than wonderful. But they will soon be out of the system......

Bosch, Denso, hell even Autolite, have all done swell by me....

Just no Champions.....

[BDRONAGOLDWING]

Has anyone used the split fire plugs, and if so can you tell any difference? I have a 1500 Goldwing that I bought used and it had Splitfire plugs in it. I have used NGK and ND and another set of Splitfire plugs but I couldn't tell a lot of difference in any of them.