737NG FMC and power settings during Touch and GO

[alistomalibu]

The scenario: 737NG
The origin airport is the same than the destination. The objective is to do a series of touch and goes.
I prepare the FMC without any data on the legs page. I do this in order to have speed bugs calculated by the FMC during the phases of flight.
I turned to downwind after takeoff. Then landing runway and Vref 30 were selected via the FMC. With this done, the speed bugs for the approach are displayed in the PFD.
After the first touch and go, all the FMC data was lost. Maybe because the FMC understood that we finished our trip. (In fact we touch at the selected destination airport)
In consequence I cannot open the FMC APPROACH page, because I don’t have a valid route anymore.

1: How can I maintain the FMC route after a touch and go in order to have access to the FMC APPROACH page?
2: How can I pre-select a takeoff power limit for the touch and go in order to advance the throttles fully forward and obtain the pre-selected takeoff power? (GA power for the Touch and go seems a lot of unnecessary power)

Thanks

[c100driver]

Simply have a point on your legs page that you will not fly over. Runway center line at 10 miles for example, this point is then alway the active waypoint and if you do not fly close to it the legs page does not sequence. Dont put an approach in as you are doing a circuit by looking out the window so it is not needed.

As for the power setting we use 88% which approx. climb thrust for a B733, and our circuit rules are no automatics so manual thrust.