Originally Posted by
DieselDan
Tandems don't have "custom spacing", just wider spacing for less dishing making a stronger wheel.
There is a good debate in the tandem community whether this is a true or perceived benefit or somewhere in-between. If you listen to Santana, it is a huge benefit but they are the only ones offering the 160mm spacing. The majority of tandem manufacturers though have no problems with wheels built with 135-145mm spacing.