This site contains affiliate links for which we may be compensated.
Shimano Tourney FC-TY501 Chainset£23.50
This extremely inexpensive crank from the Shimano Tourney series is ideally suited for MTB and trekking use due to its transmission ratio and robustness. It has three chainrings for 6/7/8-speed chains and a solid square seat (bottom bracket sold separately). The crank is also compatible with a chain box.