now this threads starting to get somewhere.
tuning issues. firstly. mount the carb solidly. if its buzzing or shaking around, the fuel will froth in the bowl. you cannot tune it if its doing that. nylon ties arent really up to the job. some type of bracket, or get someone to weld you up a new adaptor from reeds to carb flange. scavenging say, the bend from some bmx handlebars should get you the clearance AND be the right size. no point port matching one side if the other side lets everything down. one, smooth continuous piece. let the carb work properly!
mikuni and keihins have one thing in common...there are soooo many options available besides just jets! mainly needles... different lengths, thicknesses, tapers... really really complex to get right but a sheer joy when they ARE right!
i havent read anywhere anything about doing plug chops in this thread...? get a new, ngk b(r)5hs or similar. can change to a 6 or 7 later n, but 5 is good for plug chops and most riding.
the carb tuning link already posted and a few others are the best things to read, otherwise i am just repeating them, so i wont. other than, start with the main jet, and find the pdf of jennings "2 stroke tuning"(google...pretty common) and read the part about carbs. one important part is to make sure the needle jet is big enough before doing ANYTHING. pretty simple... remove main jet(yep, take it out), needle on middle clip(if it has one... a lot of keihins use washers and a fixed needle.) then try to start it.
if it wants to rev at all when the throttles opened...the needle jet needs opening up. if it bogs down, splutters and dies with a wet plug...GREAT! you can go back to jetting.
ethanol smethanol... while i wont run it anymore, simply because my road bike seized up whilst i had a tankful of it...the condition was pre-existing and not caused by fuel.
despite the 11.5:1 compression ratio...it revs harder on 91 and 95 compared to 98.
there is nothing that can be damaged by ethanol in these engines.
using high octane fuel is pointless, a waste of money, unless you enjoy running full throttle at very low speeds (lugging up steep hills with too high a gearing) or have a ridiculously high compression ratio.
maybe once you fit a decent expansion chamber, then you can use the expensive stuff, but for general use... low octanes produce more power.