What does the “D” stand for in our model names
It indicates a Derailleur gear system. This external shifting mechanism consists of a chain, multiple precision sprockets and a derailleur to "derail," or move, the chain from one sprocket to another. It's the most commonly-used system on a wide variety of bikes because it is lightweight, quick-shifting and usually offers more gears in smaller increments. When combined with a similar system in the front, operated with another derailleur, you are able to increase the total number of gears for more-experienced riders and challenging terrain. This gearing system requires you to pedal while shifting.
What does the “i” stand for in our model names
It indicates an Internal gear system. This innovative system packs all the gears inside the rear hub, much like a gearbox in a car. Shimano Nexus Internal multi-speed hubs are available in 3- or 8-speeds with wide gear ratios. The total gearing range is similar to many derailleur systems, but you simply have fewer gear choices. Internal gear systems are popular around the globe and are frequently used on leisure and city bikes because they are low-maintenance and easy-to-use. You can even change gears without pedaling or while standing still.