Grip-Shift front shifters are characterized by a number of micro stops that allow these shifters to work with a variety of FD setups, including Shimano, Sram ESP and, in my case, a quad chainring. Still after setting everything up, going over the redundant stops may become annoying. In my case I have a different number of micro stops between different gears and tend to forget their number after a break when not using the particular bike. I looked around the web for any suggestions on suppressing the micro stops that you do not use, but could not find any info, so I thought that the solution might be of use for someone once in a blue moon.
Thus, to suppress the redundant stops, I opened up the shifter and identified the indentations for the redundant stops. I thoroughly cleaned up the indentations with a combination of hot water, alcohol and mechanical rubbing. I then put a dab of slow-setting epoxy in each of the redundant stops, see the photo. This was after I waited for about 2h to make sure that the epoxy did not flow anymore, but remained sticky. After 20h or so, I put the shifter back together and now I shift directly between the stops I use.