Liz Craft’s Death Rider (Leo), which initially appeared in the Whitney Biennial in New York in 2004, now presides over the lobby gallery at the Hammer Museum. The bronze, life-size sculpture of a skeleton riding a chopper — rich in detail and solidly built — is probably more comical than sinister, though it’s definitely an ominous presence. The skeleton’s bike has a pinecone gas tank and beehive engine. A headless, limbless shell of a female figure sits behind him. His head tilted back and his fleshless face grinning, the skeleton looks to be on a joy ride, except a little patch of mushrooms has grown behind the bike’s back wheel. So maybe he’s been going nowhere for a long time.