The widest range here, and a listing with the brand name deleted
SHIMANO 105 CS-R7101, 12-speed, 11–34T
Shimano’s 105 12-speed cassette in 11-34T, the widest range on this page, for an 11 or 12-speed freehub body.
What you are getting
A Shimano 105 CS-R7101 cassette: 12-speed, 11-34T, built for the 105 Di2 drivetrain. $79.95 — the most expensive thing on this page by $21.
It publishes two different weights
Bullet two says “reduce weight (361 g (12.7 oz))”. The shipping record for the same listing says 499 g (17.6 oz).
Both come from the same page. A 12-speed 11-34 cassette at 361 g (12.7 oz) is plausible; at 499 g (17.6 oz) it would be heavy for the group. The likeliest reading is that 361 g (12.7 oz) is the cassette and 499 g (17.6 oz) is the cassette in its packaging — and Shimano does not say.
Take 361 g (12.7 oz) as the figure, note the other, and weigh it yourself if it matters.
The widest range here, and the only 12-speed
11-34T is a 3.09× spread, against 2.91× for the two 11-32 cassettes and 2.33× for the 12-28. Twelve sprockets across it means the steps stay small even at the wide end — which is the whole argument for a 12-speed drivetrain and the reason it costs what it does.
Nothing else on this page is beyond ten speeds.
And the freehub answer is almost there
“Compatible with HG 12-speed chains and designed for use with ‘s latest 12-speed and 11-speed freehub bodies.”
Read that again: “‘s latest”. The brand name has been stripped out of the template, so the sentence has a possessive with nothing in front of it. It happens twice more in the bullets — “Engineered with ‘s refined gear ratios”.
What survives is still the useful part: this needs an 11 or 12-speed freehub body. A Shimano 9/10-speed or SRAM 8-10 body — the one the XT cassette on this page fits — will not take it. That is the tag on this shelf, answered sideways.
Twelve-speed means an HG 12-speed chain, not just any chain
“Compatible with HG 12-speed chains.”
A 12-speed chain is narrower than a 10-speed one because the sprockets are closer together, and this is the same rule the chains shelf on this site states first: speed count decides the chain, and a near miss does not work at all. Buying this cassette commits the chain too.
What the five bullets actually contain
One: a refined 12-step gear combination. Two: the weight, and “durable, lightweight materials”. Three: the chain and freehub compatibility. Four: refined gear ratios. Five: a silver finish and “quiet, efficient operation”.
Three of the five are adjectives about efficiency. The two useful facts — 361 g (12.7 oz) and the freehub requirement — are buried in bullets two and three, and the individual cog teeth are never listed, where four of the six cassettes on this page list theirs.
What is not published
No cog-by-cog tooth list, no lock ring material, no construction detail (spider or loose sprockets), no ratio spread as a figure, and no resolution of 361 g against 499 g. The description adds that it is built for 105 Di2, which is electronic shifting — worth knowing before buying it for a mechanical bike, though the cassette itself is indifferent.
Availability
Read on the day this page was built: $80 at the American Amazon shop.
Read from Keepa on the day this page was last revised; stock and price both move without notice.
Prices quoted in this text were read on 2026-10-06. The live price is at the top of the page.
