It's only ticky if you don't follow and adhere to a rigid proccess that won't contaminate the readings.
For settings at WOT, the idea is to absolutely minimize any operation at other than WOT settings.
For example, let assume you don't have dyno to load the engine to peak at each throttle setting.
Instead, we'll subsitute a quarter mile or longer track, the bikes weight and the rider weight as the load. Even better would be a very long straightaway 2 miles or more, where you cold set and hold WOT at speed for a couple miles.
Start with having some new, clean, plugs on hand. Meanwhile, with the old plugs still installed, operate the engine until it is at full operating temperature. Then near the start of your track, swap the plugs with your new ones. Start up and blast down your track at WOT. When you get to the point where you have to change from Wide Open Throttle setting, simultaneously pull in the clutch and hit the kill switch and stop the bike. Pull the plugs and read them. It is important to not have any operation at other throttle settings.
It may take 2-4 runs on a quarter mile track to develop enough deposits for an acurate reading. But, don't drive your bike back to the start on the plugs you wish to read. Either trailer, tow, push, or swap your warm up plugs back in to get back to the start of your track. And, then put your "reading plugs" back in for the next run.
I recall needing something like 30-60 seconds of run time to get meaningfull deposits. Also, get yourself a magnifying glass to really see the deposit details. Especially if your center electrode insulators stay white.
Cheers,
