Simplify the following text for a Grade 6 native English-speaking person.
Original: MotÃ rhead ( Ë moÊ tÉ rhÉ d ) are a British Rock band formed in 1975 by bassist , singer and songwriter Ian Fraser Kilmister , known mostly by his stage name Lemmy , who has remained the sole constant member .
Simplified: MotÃ rhead are a British rock band . The band were started in 1975 by bassist , singer and songwriter Ian Fraser Kilmister .