Two years ago I never would have imagined that my SunRace cassette review would eventually become GRAVELBIKE’s most popular article of all time. Since that first review, SunRace has expanded their lineup to include 11-46 and 11-50 versions of the company’s popular CSMX8 ($70-$85) eleven-speed cassette. So when it came time to build up my Jones 29-plus bike, I decided to give SunRace’s 11-46 cassette a try.
Like the SunRace CSMX3 cassette reviewed in 2015, the CSMX8 utilizes a mix of loose and spider-mounted cogs. The CSMX8’s massive 46t sprocket is constructed from 7075 aluminum, while steel is used for the other ten cogs. As with Shimano and SRAM’s 11-speed mountain cassettes, the CSMX8 is compatible with standard 8/9/10-speed mountain hubs. How do you squeeze eleven cogs onto a ten-speed hub? The large cog is attached inboard of the second-position cog, which doesn’t require any additional real estate on the freehub body. Weighing in at 488 grams (11-46t, including spacers and lockring), the SunRace cassette is 36 grams lighter than SRAM’s all-steel 11-42t PG-1130.
My particular Jones frame is an older model with 135 mm rear spacing (newer versions utilize 148 mm Boost spacing). For maximum tire clearance, Jeff Jones recommended a Boost-compatible (3 mm offset) chainring instead of a conventional (6 mm offset) ring. And to make things really interesting, I opted for a mix of Shimano SLX (shifter, rear derailleur) and SRAM GX (crank, chainring, chain) components. On paper it all seemed to make sense (mostly), but the real test would be how well the various components performed on the road and trail.
Installing the CSMX8 cassette revealed a precise, snug fit with my Novatec hub’s alloy freehub body. Torquing down the alloy lockring didn’t require excessive effort, and all eleven cogs were free of wobbles. After setting the derailleur’s limit screws and dialing in cable tension, I took the bike for a test spin. Even with the bike’s mix-and-match drivetrain, shifting felt very similar to the all-XT setup that I had been riding prior to building up the Jones. Despite my best attempts to force a missed shift, the SunRace cassette performed reliably (and quietly). And although SRAM’s road 1x derailleurs aren’t rated for cogs larger than 42t, I was able to successfully pair a long-cage Rival 1 mech with the 11-46t CSMX8 (but shifting did suffer going from the 40t to 46t cog).
If you search the popular bike message boards for info on SunRace’s cassettes, you’ll come across the subject of chain derailment when backpedaling. For gravel and paved riding, backpedaling isn’t something you do very often. In technical off-road terrain, however, it’s not uncommon to backpedal slightly to avoid pedal strikes with rocks or roots. While I did experience some minor chain derailment during backpedaling on the CSMX8’s 40t and 46t cogs, I’ve observed the exact same behavior on bikes equipped with Shimano and SRAM cassettes (using both 1x and 2x setups).
SunRace’s CSMX8 is an affordable–and very capable–alternative to the big brands’ cassettes. Whether you run a Shimano or SRAM drivetrain (or a mix of both), the SunRace cassette definitely doesn’t skimp on performance. And if you’re looking to increase your bike’s gear range, the CSMX8 is a convenient substitute for the more expensive boutique extender cogs.
Disclosure: SunRace provided review samples for this article, but offered no other form of compensation in exchange for editorial coverage.