Both my left orbit and right orbit (to the ramp) shots were very weak. On my game, the ramp flap that the ball encounters in each orbit was the issue. The ball would hit the ramp flap that was too thick, get a little air, and either hit something or just have a large portion of their momentum killed.
To test for this, you can take a small piece of painters tape and tape it over the entrance to the ramp flap. (on the left orbit, I am not talking about the Bob flap, but the flap that is attached to the piece that transitions it over to the right side of the orbit)
If tape helps, what I did was, I pulled the piece and used a dremel to shorten the lip / taper the edge. Now, clean right orbit shots hit the ramp 100% of the time, and clean left orbit shots make it to the right flipper about 90% of the time. (up from about 40% of the time)
Quoted from Nokoro:
Are people able to make a full left orbit on their machines? I sometimes can, but more often the ball ends up slowing down and going into the pops. Is that normal?