Ratio Technologies launches new derailleur upgrade kit
Ratio Technologies’ new upgrade enables you to convert your bike to a 1x SRAM XPLR drivetrain without replacing your rear derailleur.
Instead, you only need to replace the chain and cassette to turn your 33 or 36t max-capacity 12-speed mechanical SRAM AXS road rear derailleur into a 1x-specific XPLR version.
The upgrade kit enabled you to run up to a 45t cassette – marginally more generous than SRAM’s 44t capacity.
The Ratio SR45X cage extends the derailleur’s B-knuckle while the cage introduces an offset upper pulley wheel.
The upgrade kit could also be a good option if you’ve damaged an XPLR derailleur – SRAM doesn’t currently offer a replacement cage for these derailleurs.
The SR45X Link will retail for £104.50 including a link or £94.50 for the cage only (international shipping available).
What’s included in the kit?
The new cage uses a 12t upper and a larger 14th lower pulley identical in size to those found on Ratio’s cages for SRAM Eagle rear derailleurs.
The cage includes 7075 aluminium plates and acetal thermoplastic pulleys. These are manufactured in-house by Ratio and assembled with stainless bearings and hardware.
You also get a custom stainless steel tool in the kit, which is required to undo the nut that holds the cage onto the derailleur.
The kit is available in black or silver and is claimed to weigh 66g, or 75g with the link.
You cannot use an Eagle cassette
Ratio Techonlogies says you must use a 12-speed XPLR or an AXS-compatible cassette, such as e*thirteen’s Helix 9-45t.
This is because the cog spacing differs between SRAM road/gravel cassettes, and its wider-ranging Eagle mountain bike cassettes.
Ratio says when you add its SR45X cage and link to a maximum capacity 33t rear derailleur, it not only increases the B-knuckle length to match the XPLR model, but also adds an offset jockey to increase the total capacity to 45t.
The brand says it did this to help the derailleur’s performance if you’re using an aftermarket cassette, such as the aforementioned e*thirteen option.
If you’re converting a derailleur with a 36t maximum capacity, Ratio recommends shortening the chain length by two links to swing the derailleur forward and reducing the B-gap.