One of the first models to adopt the AVL lean burn engine was the Royal Enfield Machismo 350, the first departure from the decades old cast iron engine used in previous Bullets. The new engine was touted as being more efficient, cleaner and more reliable than the old one. It is a turning point for Royal Enfield, which began addressing some of the long standing reliability issues that plagued earlier models, and many Royal Enfield enthusiasts believe this. But people do seem divided on whether the AVL engine actually delivered on what it promised. Some riders say they got improved reliability and fewer breakdowns, while others say they still had typical Royal Enfield problems. The problem is what ultimately happened to this engine, whether it turned out to be a genuine improvement or just a marginal one that didn't fully solve the root problem.