Recumbent

TerraTrike's 10t Deluxe Idler is designed for quiet operation and uniform wear (original polyurethane version could flat-spot). Long-wearing black Delrin material with pre-installed sealed bearing. - 54mm OD, 8mm ID (bearing ID), 15mm wide - Standard OD for easy retrofit on older trikes with single or double slotted idlers - If you have a double slotted rear idler you will need two of these plus a spacer for replacement - OEM replacement part

TerraTrike's 13t Deluxe Idler is designed for quiet operation and uniform wear. Long-wearing black Delrin material with pre-installed sealed bearing. - 63.5mm OD, 8mm ID (bearing ID), 15mm width - The larger OD of this idler may not fit older trikes or newer trikes in some locations - (best bet: replace your old idlers with the same OD replacement idler) - OEM replacement part