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After playing with jet sizes with the exhaust and intake I have settled on 27.5 pilot and 117.5 main. Needle clip 1 down from center.
The 30 pilot jet was just too big. After playing with the idle and mixture screws I finally got the best results on about 5/8ths of a turn on the mixture screw to get the best idle, For cuiosity I tried a 25 pilot, and while the mixture screw ended up in the best position right at about 1 5/8 turns out, it would pop and buck at light throttle, so it was just a tad too small. The 27.5 pilot sets the mixture screw just about 1 to 1 1/4. Once I find it's happy place I will dismount it and count the turns.
The main jet was a compromise. The 115 main works well, but was just a tad lean, but not terribly - plug was almost clean, but no signs of getting hot, if I was going for fuel economy, then it's probably the right main to have. I ran a 120 main, but it was just the opposite end of the spectrum and a tiny bit rich. With a 25 pilot the 120 main fueling was spot on, so for a hot climate this might be a good combination. With the 27.5 or 30 pilot it would just slighly load up, so if you rolled off WOT occasionally you would get a teeny tiny bit of surge. Since I bought some "between" jets laying around I decided to try the 117.5. It's perfect.
As far as the needle position goes, I initially had it set in the 4th position and moved it back to center. Since my bike spends the most time in this range and the weather is still on the hot side I chose to put it back in the 4th slot. When it gets cool at night it runs better, and on the hotter part of the day it helps it run just a bit cooler.
So obviously, now that I have my Mikuni sorted I will get my intake stuff for the OKO in a week or so lol.
I know there can be a tiny bit of variance between engines, but I have noticed that my bike really lacks power up top. Even reaching 7000rpm after the mods, it definitely falls on its face still, but with the exhaust and intake it struggles a lot less.
What my bike really gained was low end and mid-range power, and a TON of it. The 17/43 sprocket combination felt a little over geared on the stock intake and exhaust, but with both my foam element on the stock airbox w/airbox mod and the Uni Filter especially combined with the exhaust, this thing tractors along. It used to almost stall trying to idle in first gear (about 5-6mph) but now it will chug along without a care. I also find that I can be cruisin along at 35 in 4th gear and throttle on to pass without needing to downshift, where before I could do this but it took its sweet time. Rolling on the throttle hard in first gear at about 10mph damn near threw me back hard enough that I really had to hang on, and I felt myself slide back in the seat. I honestly believe I could gear this bike down even more for road use without really losing too much in the way of top speed. I won't, because I kind of like it where it is... but I could.
At this point I have couple of thoughts based on what I have experienced with the modified bike. This engine definitely has a lot of charge velocity at lower RPM but is definitely being choked off up top. Any gains from cleaning up the intake and exhaust ports on the head will definitely help on the top end. That said, I am almost wondering how well the engine will handle the OKO/PWK style flat slide with it's true 30mm bore. I don't doubt that there will be some sort of gain from the increased airflow, but I don't think the true potential of the carb will be seen until the headwork is done. Obviously, I won't know for sure until I can install it.
Oh, and new top speeds reached. 70mph on a mild downhill, 64-65 on flat ground (had a slight cross wind causing it to dance between the two). It will now cruise at 60 without the throttle being pegged. Goal reached. It still slows down to about 55 on steeper hills, but you can only ask so much from 230cc's
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