The Shimano Altus RD-M310 Rear Derailleur is a well-designed, affordable option for cyclists seeking reliable performance. This derailer features larger pulleys, with a 13-tooth top pulley and a 15-tooth bottom pulley, which help to efficiently 'use up' more chain, allowing for a compact derailer cage. This innovative design not only enhances chain management but also reduces turning friction, contributing to smoother gear shifts.
Designed for a 7 or 8-speed index and compatible with up to 9-speed friction settings, the Altus M310 can handle a maximum rear cog of 34 teeth and wraps up to 43 teeth. This makes it a versatile choice for various biking configurations. Despite its low-end market positioning, the Shimano Altus RD-M310 delivers high-end functionality, making it a favorite among budget-conscious cyclists.