Whether you use your sportbike for road riding, track days or stunting, EK has a chain that's up to the challenge. Every EK Chain is engineered with the same precision and advanced technology used in their pro racing chains. No one knows more about sealed chains than EK. After all, they invented the O-ring chain for motorcycles way back in 1974. Since then, they have improved on their invention with the revolutionary Quadra-X Ring seal. The Quadra-X Ring reduces friction by as much as 50 percent, thanks to its smaller contact area. Yet it offers even better sealing than a conventional O-ring, because it has twice as many contact points between the ring and sideplates. It's the optimal combination of maximum sealing protection with minimum friction. Many sealed chains are a trade-off: In the quest for low friction, the quality of the seal between the rings and sideplates is compromised. While such chains may offer lower friction initially, their loose tolerances ultimately lead to lubricant loss, premature wear, and increased friction in the long run. EK Quadra-X Ring chains combine reduced friction and long wear - lab tests show that they last 50 percent longer than standard O-ring chains.