Patterson Metropolis on a Terratrike Rambler

Using the Shimano Nexus internally-geared 8-speed hub on any trike gives you the enclosed reliability of planetary-geared hubs, but it's a bit slim on gear range -- particularly with a small 20" wheel on the back.

We installed a 2-speed Patterson Metropolis geared crankset on an 8-speed Nexus-equipped Rambler and economically extended its gear range up and down from the OEM spec while satisfying the owner's desire for internal (rather than derailleur-based) gearing.

There are several options for geared cranksets in the world, but the premier one is the Schlumpf drive. Schlumpf drives come in three flavors -- Mountain, Speed, and HighSpeed. They all have a 1:1 gear setting and a geared setting. They all shift by pushing a button across from one side to the other with your heel. As the dominant brand in the market, the Schlumpf drive is priced above newcomers.

The Patterson drive is a cost-effective alternative. It lacks the extensive options of the Schlumpf for satisfying all permutations of possibilities, but weighs in with a solid 28T integrated chainring and a 160% upwards gearing mode. Best of all, by just concentrating on one permutation, FSA is able to get the Patterson Drive into the marketplace at a lower cost. The Patterson drive uses a conventional shifter and incorporating a satisfactory cable stop is sometimes a barrier -- particularly on a recumbent trike.

We used a Minoura Water bottle mount on the front derailleur post for a cable stop. The mount is still useable as a front light mount.

For shifting, we used a 9-speed Microshift shifter. We had the choice of left (front) or right (rear) shifter, and decided that the rear shifter mounted upside down would give good tactile and visual feedback, so the rider can monitor the shifting position.

The gearing of this trike went from approximately 17.5-54 gear-inches to 15.4-78 gear-inches.

Our gearing calculator is quite handy for quickly doing these sorts of calculations.