This is getting a bit scattered...but a couple of things.
re: Lengths inbetween letters. (This is covered on CDave's site)
Yep. The kawi needles are proprietary and therefore do not necessarily match up to a keihin #. This was noted before, but it still being asked as a question makes me wonder where the confusion is....or IF there is any.
When there is a proprietary issue (ie: an 'L' for 'L1') you can either measure the L1 or take the available numbers on either side and determine a middle-ground #. The 'middle' isn't necessarily where the proprietary needle actually
FITS, but it will give you an idea. Doing it 'mathwise' you get a 39.27L1 for a kawi 'L' needle...that 'L' falling on either side of an oem 'F' and 'G', or 38.60 and 39.95. While that's not 39.15, I don't imagine most riders are going to be dealing with .12mm clip level changes.
An NGK 'G' series plug is a fine wire center electrode. A sharp edge to electrodes being important to a good spark, a fine wire is more likely to spark better/longer. Personally, I found a considerable improvement in a 'G' compared to an 'ES'.
But then, I found I had a better spark with an electrex lighting coil, too. So shoot me!
re: white plug with the BEP.
Who says that's a bad thing? I don't want to pollute this thread with answers that don't have any merit, but check this:
http://www.dirtrider.net/forums3/showthread.php?s=&threadid=60392&perpage=20&display=&pagenumber=1
to see where you read mixture evidence on your plug. It's not color. Granted, if your plug heat range is correct then the TEMPERATURE of the nose is indicative of A/F mixture.
INDICATIVE!! Not a direct 'measurement'.
That said, an NGK rep told me that they came up with an '8' for the KDX for a reason...that is was the correct plug for the bike. BTW...he also said that running a projected nose plug would be hazardous to the health of your bike, so don't do it!
Log? Keep a log?
I don't need no steenking log!! I remember it all!!!
...now then........where did I put my keys??? ;)