Mike Muir (born March 14, 1964 in Venice, California) is the singer for Suicidal Tendencies and Infectious Grooves.

He has also released albums solo under his nickname Cyco Miko and has sung for No Mercy, replacing original singer Kevin Guercio, who sang for the band on the Welcome to Venice compilation. Cyco Miko released two albums on the record label Suicidal Records. The album Schizophrenic Born Again Problem Child was released in 2001, following up 1996's Lost My Brain! (Once Again). No Mercy released only one album with Muir, Widespread Bloodshed/Love Runs Red on Suicidal Records.

Muir has often been seen wearing a blue bandana (leading to rumors that he and Suicidal Tendencies were involved with local gangs) and a Los Angeles Kings jersey. He speaks with something as of an inner-city, almost Chicano-sounding accent, and has both Latino and non-Latino ancestry. He is the younger brother of Jim Muir of the Z-Boys skateboarding team. Jim got Mike into hard rock music as well as skateboarding at an early age. Muir went to Santa Monica College. [1] His house was made over into a "horror house" [2] on the Discovery Channel show Monster House.

Muir has cited bands such as Black Sabbath, UFO, The Police, Van Halen and Emerson, Lake & Palmer as early musical influences, and has said that he was introduced to funk music by former bandmate Rob Trujillo. Muir incorporated funk influences into a few songs by Suicidal Tendencies and into his funk metal side project, Infectious Grooves.

Muir is known for being extremely outspoken on his views about the music industry and society. He has long been an opponent of the Parents Music Resource Center (PMRC), and has reflected this in interviews and a few songs (namely "You Can't Bring Me Down" and "Lovely"). Muir was involved in a near-violent feud with Megadeth frontman Dave Mustaine during the European Clash of the Titans tour, but the two have since reconciled and are apparently now on friendly terms .[3] He has frequently criticized rap-metal group Rage Against the Machine. The Infectious Grooves song "Do What I Tell You" mocks Rage Against The Machine (the title being a parody of the infamous "I won't do what you tell me" lyrics in "Killing In The Name").

His singing voice has been compared to that of Heffer Wolfe, a character on the 1990s cartoon Rocko's Modern Life.