In review, I see you addressed a question to me on air/fuel mix adjustment. It looks like I didn't respond -- sorry for that. There is an idle adjustment screw on your motor (air/fuel) as you are aware. Close it carefully clockwise, and from it's seated position open it about 1 turn or a little more. The motor should run -- start and warm it up, then at a slow idle (or as slow as it will keep running), slowly turn the needle clockwise (leaner -- less fuel) about 1/8 turn at a time, letting the motor catch up. Do this until the motor lean sneezes (sounds like a light backfire) or wants to stall. At that point, open the needle about 1/4 turn and this should be a correct setting. The adjustment requires some back pressure, so do it with the motor in a barrel (water about half way up the leg) or in the lake. You want the leanest setting at which the motor idles well and shifts into gear without stalling. For cold starting, I sometimes enrichen the setting a bit until it starts and runs, then go back to the leaner run position. The high speed jet is fixed on your motor -- jet must be clean, but no additional adjustment.
On the roller/cam follower: adjusting the roller is part of the "link and sync" procedure. The black plastic cam under the retainer and link assembly is held in place by friction. You should not be able to move it with your finger. There is a marker on the cam that shows where the roller must be when it initially contacts the cam (by rotating the grip counter clockwise). When it touches that point, tighten the screw just enough to hold the position. When you turn the grip fully clockwise (slow), the roller will not be in contact with the cam, but the motor will continue to run if clean and tuned. There is a throttle stop to control how slowly you want the motor to run. On mine, I sometimes set them to keep slowly idling until I use the shut-off button (or choke).
As the cam moves counter clockwise with the timing plate (grip twisted clockwise to throttle up), the roller will hit the high point of the cam, fully opening the throttle plate. (Note -- until the roller touches the cam marker on the slow end, the throttle plate will be closed.)
Hope this helps.
