All Ryuken units paint their BattleMechs charcoal gray. The members of Ryuken-roku accent their BattleMechs and other vehicles with red.

Per FM:Draconis Combine, page 131.

Other references:
Trebuchet, CM: Kurita (p 104)
Highlander, CM: Kurita (p 108)


Insignia:

The Ryuken apply the Kurita dragon crest to their BattleMechs on the left leg just above the knee and near the exhaust ports of fighters. The Ryuken insignia is a dragon curling around a Katana sword, both drawn with rich detail. The regimental insignia, laid directly against the gray of the vehicle, is a rough drawing of a hand holding a sword by the blade. Per FM: Draconis Combine, pages 126 and 131.