I have 2001 Roadking police, I bought the bike 3 years ago. It had open 3inch pipes, and backfired a lot, I put on some kirkers with turn downs, it still backfired, the dealer put another computer on it from another 01 bike it was an Electra Glide, didn't work then put on a Teclution fuel management system, just used more fuel than before still backfiring. They then checked the intake had a leak fixed no changes. While doing these things i'm going through sparkplugs tried cheap plugs and expensive plugs no change. The bike will not even idol now, the only way its rideable is at 3000 rpm.