A three-piece, 5-arm aluminum carrier holds all of the 6 largest cogs on this cassette. This design lightens the overall package while stiffening the body for better shifting performance. The stress and load is also spread out along the carrier, reducing wear on the freehub body on the hub. All cogs are perfectly machined using Shimano proven Hyperglide II design. Lower 5 cogs a drilled and treated steel, while the upper 4 cogs are drilled titanium for added durability. Super lightweight and anodized alloy lockring included.
The M970 is Shimano's lightest and best engineered 9-speed mountain bike cassette ever developed. The alloy carriers and titanium cogs bring the final weight in at a scant 224 grams.
Gear ratio breakdown