12 Speed Cassette Comparison: XTR CS-M9101 vs Dura-Ace CS-R9200

Hot on the heels of the previous comparison post (12 speed vs 11 speed): Instead of comparing within the same category (XTR to XTR, or XTR to Deore XT), I can also compare across categories, from MTB to Road. This kind of cross-category comparison is usually not meaningful, as they have very different intended usage. For example, it is not so useful to compare shifters, derailleurs or cranksets across categories.

For cassettes, cross-category comparisons are possible, because the design and intended usage is more similar. In fact, old MTB cassettes (up to 42T sprocket) has becomes the new gravel cassettes. A more extreme case is that older MTB cassette ratios such as 11-34T for a 2x10 or 3x10 speed MTB drivetrain, is now found on road bike cassettes nowadays.

Today's comparison will be rather brief, as the details of each cassette can be found in their respective posts. This time, the comparison is between two 12 speed cassettes. The XTR 10-51T CS-M9101 vs Dura-Ace 11-30T CS-R9200.

Large 10-51T 12 speed cassette, the XTR CS-M9101. It is also available in a tighter 10-45T specification.

Dura-Ace 12 speed cassette, CS-R9200 is available in 11-30T and 11-34T versions.

370 grams for the 10-51T XTR cassette, considered lightweight given its size.

Just 256 grams for the 11-30T Dura-Ace cassette.

XTR 10-51T cassette has the 8 largest sprockets riveted to a single aluminium spider, and 4 loose sprockets. There are 3 aluminium, 5 titanium and 4 steel sprockets.

Dura-Ace 11-30T cassette has 7 sprockets riveted to 2 spiders, with 5 loose sprockets.

There are no aluminium sprockets, 6 titanium and 6 steel sprockets.

Big difference in size! The gear range is also vastly different, XTR 510% vs Dura-Ace 272%.

Both use a large aluminium spider construction to save weight, and clever riveting design between sprockets to reinforce each other.

Both are 14T sprockets, but from different cassettes. XTR 14T Microspline on the left, Dura-Ace 14T Road L2 spline on the right.

Elaborating more on the 14T sprocket comparison picture above, for those who love details.

Differences include:

1) Microspline vs Road L2 spline pattern. Microspline has a smaller diameter.

2) Road L2 spline sprockets are also backward compatible to HG freehub bodies. Microspline sprockets are not backward compatible to any other freehub body.

3) Teeth profile is different due to different neighbouring sprocket sizes. The Microspline 14T sprocket has to match the 12T and 16T sprocket before and after it, while the road 14T sprocket has to match the 13T and 15T sprockets.

4) This 14T Microspline sprocket has a step stamped onto it, to make space for the 12T sprocket to engage the Microspline freehub body. The road 14T sprocket is basically flat.

Similarities include:

1) Both have the same teeth diameter, as the chain pitch is the same (1/2 inch chain pitch).

2) Both use the same Shimano 12 speed HG+ chain, common for Shimano road and MTB.

At the end of this post, I am not sure how useful this comparison post is, as it is probably one of the first cross-category comparison post that I have done. Some interesting findings though, from the side by side comparison.