The Shimano Deore XT CS-M770 Cassette takes all the ramping and weight-relieving of previous generations -- not like that stuff would go away -- and adds a cool new feature: pins on the backside of the tallest cog.

At first, the innovation seems like sloppiness or poor manufacturing tolerances. It shouldn't be either, as they mastered keeping the rivets that hold the tallest cogs flush before. The reason for this simple innovation is incredibly practical -- it can prevent the chain from wedging in between the spokes and cogs in the occurrence of an over shift. Kind of an ounce of prevention improvement that could yield several pounds of cure if it means the difference between wrecking a wheel or not, or walking vs. riding home.

The Shimano Deore XT CS-M770 Cassette is offered in two ratios: 11/32 and 11/34. The 11/34 has a five-arm spider for the six largest cogs while the 11/32 has a four-arm spider for those same six cogs. The three smallest cogs in both cases are loose. 297g. MSRP $99.99.