in general when you increase bore and stroke you will need to stay the same or go down on the main. if you search my posts i did an indepth write up on jetting if you want details. but in short no matter the cylinder volume the air to fuel ratio needs to stay the same. where guys get messed up on big bore stuff is its common belief bigger bore needs more fuel. in reality a big bore makes significantly more vacuum so it pulls more fuel through the same jet so it feels backwards. on a 2 stroke is is really important to do plug chops. run it and see what the plug looks like and adjust from there. my guess is you need a higher octane with the increased compression. if you plug looks good try running 25 percent jp race fuel and see if it fixes you issue. let me know if you need more help
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