Originally Posted by
cyccommute
The Troll complete comes with a 12-36 cassette and with a 48/36/26 crankset. That's actually a pretty good base to start with. I'd not change out the crankset or the cassette. The only thing needed for a much lower gear is a new inner ring on the front. The 64mm bolt circle diameter (BCD) on the crank can take chainwheels down to 20 teeth, although a 20 tooth inner is a little hard to find. A 22 inner is more "normal". That's still a good low gear with a 36 tooth cog on the cassette (15 gear inches).
I would keep the 48 outer, however. At 100 rpm, a 12 tooth high cog will spin out at 27 mph with a 42 tooth ring but won't spin out until 31mph with the 48 tooth ring. It's not a huge difference but any thing you go up you'll want to come down. Coasting down long downhills gets tedious quickly.
I stand corrected, for some reason I was thinking it had an 11-34 cassette on the back and a standard 22-32-44 crankset, should have looked at the specs before posting. With that being the case, if you need a lower gear like cyccommute pointed out just swapping the small ring to a 22t is the way to go.