Ratio Technology chainring review

UK gear disruptors, Ratio, only does one chainring in one size but it’s great at what it does

Ratio Technology chainring review
(Image: © Guy Kesteven)

BikePerfect Verdict

Super-clean drive feel and reliable chain security across a full range of transmission brands but only comes in one size and five-bolt fitting


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    SRAM Flattop and Eagle, or Campagnolo Ekar compatible

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    Clean drive feels and easy release but is still secure

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    Handles high torque

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    Reasonably priced


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    Only comes in one size

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We’ve already tested the ‘more gears for the masses’ 12-speed upgrade kit from Ratio but the UK transmission innovators also makes its own chainring for gravel riding. It’s really good, too, particularly if you’re looking for the best 1x chainring alternative to SRAM. Only if you’ve got a five-bolt chainset and want a 38T size though as that's the only option Ratio offers.

Design and performance

Looking at the Ratio Ring, there’s nothing particularly outstanding or ‘special’ about it until you get up close and realize the scoop between each tooth is actually asymmetric, with a shallower curve on the rear, driving face. This profile means it’s the only aftermarket ring we’ve used so far that genuinely handles the larger 7.9mm rollers of SRAM’s Flattop chains without grumbling or rumbling. While the five-bolt design won’t fit an actual Ekar spider, a quick crank switch to a Campagnolo Ekar set up during testing proved 13 gears isn’t an unlucky number for the ring either. 

According to Ratio, the shaping also helps the classic narrow-wide tooth arrangement clear the slack part of the chain more cleanly so there’s less chance of hanging up when things start to get dirty and that’s certainly not caused issues so far. Scooped front webs on the bolt tabs look classy and together with cutaways on the back keep the 7075 T6 ring light. It can still handle serious torque though and we’ve been running them as a final drive on a tandem without any folding or warping issues. It’s chamfered slightly on the drive face to squeeze debris out, too, so gravel and CX riders will benefit from a cleaner connection and less chance of gumming up when courses get filthy. It’s fairly priced for a UK-made product that’s clearly had a lot of thought put into it, and significantly cheaper than official SRAM or Campagnolo rings.

The only downside is the fact it only comes in a five bolt, 110bcd format and 38T size. That fits with Ratio’s main business of converting older transmissions to a single ring, 12-speed Eagle or Xplorer cassette setups and 38T will suit a lot of people. The tooth set up works so well we’d love to see them adding other options to the menu soon though.

Ratio Technology chainring close up of the teeth profile

The tooth profile works well on SRAM and Campagnolo, although the chainring only comes in one size (Image credit: Guy Kesteven)


Ratio’s ring plays really nicely with SRAM Flattop and Campagnolo Ekar transmissions for much less than official options and works conspicuously cleanly even in filthy conditions or under high torque loads. All we need now is more ring sizes and fit options please Ratio.

Tech Specs: Ratio chainring

  • Price: $N/A / £70
  • Weight: 57g (38T)
  • Sizes: 38T
  • Colors: Black
Guy Kesteven

Guy has been working on Bike Perfect since we launched in 2019. Hatched in Yorkshire he's been hardened by riding round it in all weathers since he was a kid. He spent a few years working in bike shops and warehouses before starting writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. To make sure he rarely sleeps and to fund his custom tandem habit, he’s also penned a handful of bike-related books and talks to a GoPro for YouTube, too.

Current rides: Cervelo ZFS-5, Forbidden Druid V2, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg