Ah, so I was looking at the system in reverse! That would explain why I thought drilling the slide would operate oppositely than what it does.
On a side/ yet related note, I just came in from a ride with the KLX stuff newly installed. I'll attach a pic of the spark plug as I found it before putting the new needle in, but it's far from an accurate plug reading. I've been riding around the farm doing chores, regardless, there definitely didn't seem to be any lean condition present.
With the KLX needle and all associated parts installed per the directions ( clips and such) the first difference I saw is that it's harder to wheelie. It requires more throttle input and it comes up less smoothly.
Power below 2500 IMO is boggish now. If you whack the throttle there's a hesitation followed by the bike coming back to life. It runs no better than before, it just bogs lightly then perks back up. Perhaps this is the "snappiness" that others are feeling? Power above 3500 rpm seems unchanged IMO. Previously I had the stock needle shimmed up and the issue mixture richened to 1.75 turns, so I wasn't exactly starting from scratch, in all fairness to the KLX kit.
These symptoms describe a rich condition to me. Yet, my fan is running more often than before. However, in all fairness regarding the fan, I am really riding the 14T sprocket extensively for the first time, so that may be related to that. I'm not riding at higher rpm now, but i am able to travel slower and ride the more technical areas that I life, so I may just be putting more strain on the engine due to that. Temp needle is glued in the center like always, ever consistent, so there's been no rise or fall in operating temp.
So, maybe I do need to drill that hole, but I'm not sure a sluggish slide is my issue now. Perhaps I'll drop the needle a bit and see how she responds.
Thanks again for the help on the CV stuff, guys. Damocles, yes, I did read the things you asked me to read. I've been playing with carbureted racing engines ( American V-8's)for almost 20 years now and all of my personal vehicles have been carbureted with non-stock engine combinations. Carb tuning isn't new to me, or intimidating. It's actually something I enjoy! Getting 22mpg out of a four speed '66 Impala SS was a fun adventure
But the vacuum slide mechanism is definitely something I never experienced before a couple years ago when I ended up with a dohc CB750. Every day is a school day....
Oh, and I was happy to see a respectable number with this compression test. Although, with the auto decomp installed on this engine I was not really sure what to expect. Thoughts on that? I guess I could ask my manual, huh? lol