Clearing Up Spark Plug Confusion

I'm satisfied with this answer…

On the official Triumph site, they sell both the 8 and 7 plugs.

On the page for the 8 plugs, under Details/Technical Information, this plug is listed for use by nearly 30 models, NOT including ANY Rockets: NGK DPR8-9EA

On the page for the 7 plugs, they list ONLY the R3 Classic, Roadster, and Touring: NGK DPR7-9EA

So, the 8 has been their go-to plug for many models for a long time, and they only deviate from it for specific reasons. On the 8 page, some of the models listed are only for particular VIN ranges. This shows they are detailed in their descriptions, and if they only meant for 7 plugs to be used in Rockets from a certain point forward, they would specify that. They clearly intend to switch to the 7 plugs in ALL Rockets.

Why? I haven't been able to find any definitive information on this from the Triumph engineers or secondhand sources, but based on the info in that NGK link above, there's a good chance they were seeing enough fouling to make the switch to a hotter plug.

My Conclusion: In this case it's not as simple as replacing the plugs that were already installed, as indicated in replies above. Triumph learned something that justified switching plugs, and while the 8s may continue to work perfectly well for many Rockets, I'm convinced it's worth making the switch to 7s in older models.
Just throwing this out there, and I'm probably way off...

Didn't the original R3 come with no cat, then later had cat in the crossover box, later to be put in the tailpipe of the R3R? Maybe the 8 was ok with no cat, then later models needed a hotter plug to reduce plugging of the cat.
 
I have a friend that races bikes in the UK he told me the 7's start quicker and last longer.He might have something there considering my 2005 never really instantaneously starts,it always starts but not like a Honda engine.i also have heard it said that pre 07 the Rockets ran cooler and richer. I really can't find anyone out there that can give me a definitive answer...??
 
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I run all year and even in real cold conditions have never had a problem with the bike starting. Even in unprotected weather down in the teens the bike has always fired up right away. Read a couple of post where folks have had a problem getting their bikes to start under these conditions but has never been a issue. Spark plugs?:unsure::unsure::unsure::unsure::unsure::unsure::unsure::unsure::unsure:
 
I run all year and even in real cold conditions have never had a problem with the bike starting. Even in unprotected weather down in the teens the bike has always fired up right away. Read a couple of post where folks have had a problem getting their bikes to start under these conditions but has never been a issue. Spark plugs?:unsure::unsure::unsure::unsure::unsure::unsure::unsure::unsure::unsure:

Batteries more like ;)
 
just my opinion
i would not run any plug for 100.000 miles if u do u might not be able to get it out of the head or it brings all the threads out with the plug.
also plugs going down i blow them out with compressed air before removing so a little rock or something goes into the cyl. on some ford motors u have to break them loose then spray them good and let them soak so u don't break the end of the plug off in the head.
Ahh the LS Chevy heads have the same problem. In fact, even more so, but GM has the government funded soapbox to point out every other engine's faults.
 
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