I love my Vulcan 900 and have had virtually no problems since owning. I have however had a pesky rear brake issue. Riding one day I noticed the rear brake pedal would go all the way down; no rear brake. I noticed no leaks in the garage or on the bike. I bled the rear brake and pressure returned. I tightened everything down and thought everything was good. Within days same problem and again no leaks. I figured air had to be getting in somehow so figured I'd rebuild the rear master cylinder. I ordered a kit (darkhorsemotorcycleparts.com $20) and spent 30 minutes rebuilding and bleeding system. After two weeks it would appear the problem is resolved. I post this as an FYI as I didn't see this problem specifically in the forum and should it be encountered it's a cheap and quick fix.