All Ryuken units paint their BattleMechs charcoal gray. The Ryuken-ni MechWarriors accent thier 'Mechs in silver, sparingly applying the color along sharp edges to imitate the edge of a blade.
Per FM:Draconis Combine, page 126.
Bishamon, Kage BA, Combat Equipment Guide (color plate 4) Mad Cat II, Phoenix Hawk IIC, Total Warfare (p.38)
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 regiment's insignia, displayed on each 'Mech's head is a fierce-looking feline head wearing a Japanese-style kabuto helm. Per FM: Draconis Combine, pages 126 and 127.