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After recently servicing the trumpet including a full tune and carby balance I decided to pull the plugs after a freeway run of about 45kM @ 145kMph and a short suburban run of about 5kM @ about70kMph and this is what I found:
the plug on the right is from the right cylinder. my set up is... Unifilter with modified air box- no snorkels, TBS needles no shims, 45 pilots, 135 mains, and pretty much open pipes, about 3 turns on the air screws. balanced carbs.

So why the difference in the two plugs?
Is this difference going to cause me a problem? Is one plug better than the other? these are iridium plugs. Any ideas?????

first off make sure your carbs are balanced, 2nd not all carbd are exactly the same so the air screws may need to be adjusted a little different

Frank

What frank said. Make sure the carbs are balanced, then tune each idle mixture for best idle speed + maybe 1/8 turn. No need to pull the opposite plug wire to do this, just reset the idle speed when it gets running noticably fast. The extra 1/8 turn is so it will run a little cooler, important in the summer.
Also, swap the plugs and make sure the difference stays with the cylinder instead of following the plug, it's always possible that they are different.

You might also want to check for air leaks. The clamps on the rubber joints between the carbs and the intake, and also where the exhaust manifold mounts to the head.