There's been a thread lately on some of the spinning lists about how to ply on a Little Gem 2. I've heard some very strange comments about crossing drive bands and even the bobbin cord. One even said they use a rubber band for tensioning their bobbin!
Some people may be a little confused about which band/cord they are referencing. The Little Gem has a lower drive band that is very thick, an upper drive band that is much thinner, and a bobbin cord that controls the tension on the bobbin.
The lower drive band runs from between the treadles to the front of the bigger wheel above it. I never mess with this lower drive band. If you fold the wheel up, you have to move this drive band to the side. It's not easy to get it back in place. My dealer tells me it's easiest to "roll" it back into place. When transporting my wheel in the car, I place my Little Gem facing backwards in a seat and fasten the seatbelt over it to hold it in place.
The upper drive band goes around the middle of the bigger wheel and the whorl above it. The instruction book directs you to "cross" this drive band when you are plying. I would suggest that you not do this. If you do, it will wear out your drive band where it crosses and rubs against itself. It isn't necessary anyway. It's very easy to get the wheel to spin in a counter clockwise direction for plying without crossing this band.
Here's a closeup picture of the bobbin tension knob and cord. The nylon cord wraps clockwise around the knob, goes over the bobbin, and attaches to a spring that is looped over the bobbin tension knob. The spring helps control the tension on the bobbin.
Turn the knob to the right to make the yarn feed onto the bobbin faster. The spring will expand.
Turn the knob to the left to slow the speed the yarn feeds onto the bobbin. It will add more twist to your single. The spring will contract.
You don't have to turn the knob very much to change the tension on the bobbin. Once I set the bobbin tension for the fiber I'm spinning, I move it in very small increments as the bobbin fills and I need more "pull" onto the bobbin.
The bobbin cord position never changes for spinning or plying. When I'm not using the wheel for a day or so, I slide the bobbin cord off the bobbin. This saves wear and tear on the cord and the spring.
Another note on plying, some people change the flyer hook from the right side to the left side of the flyer when they're plying. I've tried it both ways and I can find no difference. I always leave the flyer hook on the right side of the flyer.
I hope this helps.