Extra-wide seat pad — more comfort for all passengers

The Gen 2 seat pad is wider than standard Tern seat pads — the additional width gives adult passengers more hip support and children a more stable, enveloping seat. A wider seat also accommodates the side-by-side position of two children on the GSD more naturally than a narrow pad. The extra width is the primary ergonomic upgrade from a simpler Sidekick Seat Pad to the Captain's Chair.

Longer side rails — handholds and armrests in one

The side rails extend further than those on a standard Tern rear seat — long enough to function as armrests when the passenger sits with arms resting to the sides, and grippy enough to serve as handholds during acceleration, braking, or cornering. A passenger who can rest their arms on the rails rather than gripping tight throughout the ride is significantly more comfortable on longer journeys. The rails also serve as the attachment interface for Sidekick Wheel Guards and other Passenger System accessories.

Rear bar — bags, baskets, and lights

The rear bar behind the seat provides a dedicated attachment point for a bag (drawstring, tote, or specific accessory), a small basket, or a rear safety light. On a bike configured primarily for passengers, the rear bar allows a small cargo item to remain mounted even while carrying a passenger — the passenger sits forward of the bar, the item hangs behind. It's also a natural position for a bright rear light that's not obscured by a passenger's body.

GSD: one adult or two children

The GSD's longer rear platform is specifically designed to accommodate two passengers simultaneously. With the Captain's Chair, this means one adult sitting conventionally or two children seated side by side. The GSD's total capacity, the rear rack's load rating, and the overall bike weight must all be considered when loading two passengers — the Passenger Guide specifies the configuration requirements in detail. No other compatible model (HSD, Quick Haul, Short Haul) is rated for two simultaneous passengers.

Cargo configuration with Sidekick Joyride Bars

When the Sidekick Joyride Bars are installed alongside the Captain's Chair, the combination creates clearance for boxes or crates in the seat area — useful when switching between passenger and cargo configurations without removing the chair entirely. The Cargo Guide specifies what can be carried in this configuration and how to secure it. The Captain's Chair's rear bar provides an additional attachment point for cargo security in this mode.

Captain's Chair vs Sidekick Seat Pad — the key difference

The Sidekick Seat Pad ($90) is a padded insert that clips to a compatible rear rack via KLICKfix Rackpack — minimal, lightweight, quick to install and remove. The Captain's Chair Gen 2 ($379) is a full structural seat with rails, a rear bar, and significantly more comfort for longer or more frequent passenger use. For occasional passenger transport, the Sidekick Seat Pad is the economical starting point. For regular passenger use or two-child GSD configurations, the Captain's Chair provides the appropriate comfort and structural support.