11-25 12s monoblock does not fit GRX
Same experience as A.P en Kim Visby.
Tried all options, even bought the adviced chain. Shifting is off. Contact with support is not very warm.
Do not buy.
March 1, 2026
Unprompted review
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Sub-average product. Terrible support.
I bought a 12-speed Shimano cassette for a lightweight bike build.
11/12th of the cassette work well, but the smallest sprocket keeps skipping.
I was in communication with support, who kept telling me it was due to wrongly indexing the gears, despite me telling them that it was not the case.
I supplied images and videos - and my mechanic's opinion - that the gears are aligned properly, but was ignored.
At this point I was told that specific chains are recommended (SRAM and YBN), and the cassette won't work with Ultegra or KMC chains - but this information, quite cheekily, is nowhere on their website.
When I pointed out that this info should be displayed on the product page, they stopped replying to my emails.
The info was then added to the website. I was not thanked, and they still have not replied. :)
Extremely petty and unprofessional - and you cannot afford pettiness when your product is not good enough.
August 14, 2025
Unprompted review
Shimano 12 speed monoblock will not…
The Shimano 12 speed monoblock will not fit your system..
The monoblock are not machined precise enough so that a smooth gear shifting can be obtained.
After three bike shops tried to make the derailleur adjustment I gave up and got a original shimano cassette.. and that solved all problems.
The shop did not try to reject the issues with their cassettes and elaborated further that shimano cassettes are hard to copy.
However the shop were unwilling to take back the useless cassette.
I cannot recommend a monoblock cassette from this shop as it will not work
And I cannot recommend shopping at this webshop in general based on the support and experience with a fault product.
October 1, 2022
Unprompted review
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