Nightrider X14iED Fuel Enrichment for EFI Harley-Davidson Plug - n - Play DK-X14iED-NR The Plug-n-Play X14iED richens the Air Fuel Ratio from 14.6:1 to 14.0:1 in closed loop mode. Immediate Benefits: Lower Engine Temperature - Lower Exhaust Temperature - Improved Throttle Response - Reduced Surging - Reduced Pinging Recommended for: Stock Configuration - High flow air cleaner - High flow exhaust - "Stage 1" (both high flow exhaust & air cleaner) The X14iED's are a cost effective alternative to an aftermarket tuner & dyno runs. X14iED's will cool your bike down and make it run better.