engine shakey at mid speed

ok i will try to back it off and rev it back. so far it just comes back rough when i throttle back up. i will try some more i hope i havent toasted my engine
 
my idea here is that you shouldnt hit the rough spot.
when its "getting there" and you know it, return to idle. come onto the throttle very slowly and consistently hold tune
 
Your probably doing what's called 4 cycling at mid rpm's. The motor is only firing on every other stroke. It's kinda normal when braking in. Your next gallon of gas goto 7 or 6 oz of oil. That will help, also your at the point that some extended periods of higher speed will finish setting the rings. As it gets broken in the rest of the way and you reduce the oil it will get alot better. You really can't tune the carb very well till it's broken in all the way. Check around the head for any oil. Your getting about to the point you may need to re-torque the headbolts.
 
hey thanks guys I am getting close to the end of Gallon #1 at 16:1. It is gettin better and I will check those bolts.
 
Flat spot caused by extreme richness at low end followed by leaner mixture when the needle valve takes over.

The easiest fix I've found is to add a slant high compression head. It automatically leans out the low end and the high end is richened by needle clip adjustment.
 
OK switched to 32:1 with standard 2 stroke oil. haven't gone on any super far ride but have definitely warmed it up once. The engine still hits a spot at mid speed ( maybe where the main jets take over? ) and it chugs, once through the chugging stage it accelerates nicely. It does it more when going up hills. do i need more oil than 32:1 I checked the plug ant it looks black/ brown and slightly wet, not gooey and clogged...
 
switched the needle pin settings and and no improvement anywhere. also switched to 87 octane from 91 and no real changes.
 
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