Circa 1973 GRM Islo Trialsmaster motorcycle photos & specs

GRM ISLO Trialsmaster – designed by Bill Grapevine and manufactured by Moto Islo S.A. of Satillo, Mexico. (GRM stands for Grapevine Racing Motors). The Only 250cc class trials bike that uses a frame made of aircraft quality 4130 steel tubing imported into Mexico from the U.S.A.

1973-circa GRM Islo Trialsmaster Dealer Sheet available at

Comments are closed.