Plug color feedback

plug looks ok for now... Top speed is about right for the 44 tooth, it'll get a little better as it breaks in some more.
if the top end feels ok for now then keep whatever jet you're running in there, for the low end four stroking, you can either leave it be or move your needle down a notch by raising the clip up a notch and see if it goes away.

he plug should be ok but you could try one step hotter on the plug and take a new reading, you're making progress.

I would run 50:1 or 40:1, 100:1 though doable just is not what these motors are made for. The tolerances and materials like more lube than 100:1. The highest speed I've seen with a 44 was 38 mph. Do a little piston trimming and open up the transfer ports and 35 is totally feasible. 38 mph was on a stock bottom end with some dremmel mods. What is considered not stock?

There are several of us running Opti2 at 100:1 in here and have been running that mix for years with no issues... We got past that part already.

As for the reason his bike is slow right now it's because it's a brand new engine and not even close to broken in yet... His bike will go fast after he gets some more seat time on it for sure with the mods he has. I can't tell all, but I know he has a Fred head and a ported jug, and possibly a pipe and a cut piston so it's just a matter of breaking in the engine and more fine tuning then it'll be fast.

I'd say if it's tolerable let it break in and see if the 4 stroking on the bottom end goes away as the engine frees it's self up... Right now the engine has to push harder against the friction of the cylinder as well as the excessive blow by before the rings seat, this will improve as you ride it more and may end up right where you want it after a few more hours of run time. The other thing is 4 miles is probably about where the engine is just beginning to warm up to operating temperature, try to run it about twice that distance next ride, keep it close to home, but do the same ride twice if you need to and see how it goes.
As long as it's all tolerable I'd leave it alone and put some miles on it.