High quality replacement spark plug, these are what most Japanese motorcycles come with from the factory.  Please double check your spark plug number before ordering - these fit a ton of bikes but it is always best to be sure. 

Key Features:

• 98% pure copper core increases heat dissipation for more reliable starts and prevents spark plug from overheating
• High-grade alumina silicate ceramic insulator for superior strength and heat transfer
• Cold-rolled threads to prevent cross-threading and damage to cylinder heads
• Trivalent plating eliminates need for anti-seize and corrugated ribs prevent flashover