Home » Ratio Upgrade Kits

Ratio Upgrade Kits

Ratio upgrade kits help you keep your bike up-to-date without the waste and expense of replacing otherwise functional parts, whether that’s switching from 11 to 12 speed, 10 to 12, wide range or narrow.

We’ve compiled this guide to help you understand the options that we’ve made available.You can also find a list of FAQs; if you can’t see an answer to your question, just drop us a message. You can also check out our Support page for instructions and video guides.

Green is our recommended option. Amber has been used by some customers but is currently un-tested by us and a red part has been confirmed to be incompatible.


1×12 Road

Image credit: www.horsepowercoaching.co.uk // www.wheelsbytc.co.uk

What’s it for?

The 1×12 Road kit allows you to upgrade your SRAM 1×11 drivetrain to close ratio 1×12 using SRAM’s road AXS™ 12 speed cassettes (Red™, Force™ and Rival™) and Flattop™ chains. These cassettes have proprietary sprocket positions, so the 1×12 Road kit is specific to SRAM road 12 speed cassettes.

What’s in the kit?

In the kit you’ll find a 1×12 Road ratchet for your SRAM road shifters and a set of 12 tooth jockey wheels for your SRAM road 1x derailleur. These jockeys allow you to run SRAM’s Flattop™ chains, which are a requirement of the road 12 speed cassettes. Our jockeys run on long-lasting stainless Enduro bearings.

1×12 Road Compatibility:

Green – Recommended

Amber – Untested but fine in most cases

Red – Not recommended

Derailleurs

  1. SRAM Force 1™, Rival 1™ and Apex 1™
  2. SRAM 1×11 mtb derailleur with Ratio cable fin
  3. Other SRAM Exact Actuation™ derailleurs with sufficient sprocket capacity

Shifters

  1. SRAM 11 speed road all models
  2. SRAM 10 speed road (using Ratio Cable Spool)

Cassettes

  1. SRAM road AXS™ all models (including XPLR™)
  2. SRAM Eagle™
  3. All third party 12 speed cassettes

Chains

  1. SRAM Flattop™ all models
  2. SRAM Eagle™
  3. Shimano 12 speed

Chainrings

  1. Ratio Ring
  2. 1×12 Flattop™ chainrings
  3. 1×12 chainrings
  4. 1×11 chainrings


1×12 Wide Ratchet and Cage

What’s it for?

The 1×12 Wide Ratchet and Cage kit is designed for SRAM 1×11 riders who want the increased range of a 12 speed Eagle™-compatible cassette with a minimum of new parts. Instead of replacing a totally functional road 1×11 derailleur with a new Eagle™ version, simply fit our extended cage to increase the sprocket capacity of the derailleur for a wide-range cassette.

What’s in the kit?

This kit includes our 1×12 Wide ratchet for wide-range 12 speed cassettes and a Garbaruk cage with Ratio jockeys for your SRAM 1×11 rear derailleur. Our jockeys run on wear-resistant stainless Enduro bearings and are made of quiet, low friction nylon.

1×12 Wide Ratchet and cage compatibility:

Green – Recommended

Amber – Untested but fine in most cases

Red – Not recommended

Derailleurs

  1. SRAM Force 1™, Rival 1™ and Apex 1™ (the cage works with both Type 2.1 and Type 3 clutches)
  2. SRAM 1×11 MTB derailleur with Ratio cable fin

Shifters

  1. SRAM 11 speed road all models
  2. SRAM 10 speed road (using Ratio Cable Spool)

Cassettes

  1. SRAM Eagle™ all models
  2. e*Thirteen
  3. Garbaruk
  4. Rotor
  5. Ingrid
  6. Leonardi
  7. SRAM road AXS™ 12 speed
  8. Shimano 12 speed

Chains

  1. SRAM Eagle™ all models
  2. KMC 12 speed
  3. Shimano 12 speed

Chainrings

  1. Ratio Ring
  2. 1×12 chainrings
  3. 1×11 chainrings
  4. 1×10 chainrings


1×12 Wide Rear Exit

Image credit: @hee_said

What’s it for?

Upgrade your SRAM 1×11 drivetrain to wide-range, mechanical 1×12 using SRAM Eagle™ components. The rear exit version of the kit allows you to fit an Eagle™ derailleur to frames where it wouldn’t otherwise be possible – for more information, check the “Forward vs. Rear Exit” section of this guide.

What’s in the kit?

The 1×12 Wide Rear Exit kit includes a 1×12 Wide ratchet for Eagle™ 12 speed indexing, a cable fin to convert Eagle™ derailleurs to Exact Actuation™ (allowing them to work with SRAM road shifters) and a Rear Exit cable stop to change the cable routing on your Eagle™ derailleur. There’s also a plug to keep dirt out of the original cable port.

1×12 Wide Rear Exit Compatibility:

Green – Recommended

Amber – Untested but fine in most cases

Red – Not recommended

Derailleurs

  1. SRAM Eagle ™ X01™ and XX1™
  2. Ratio pre-fitted SRAM Eagle™ GX™ in a Rear Exit Bundle
  3. SRAM Eagle™ GX™, NX™ and SX™

Shifters

  1. SRAM 11 speed road all models
  2. SRAM 10 speed road (using Ratio Cable Spool)

Cassettes

  1. SRAM Eagle™ all models
  2. e*Thirteen
  3. Garbaruk
  4. Rotor
  5. Ingrid
  6. Leonardi
  7. SRAM road AXS™ 12 speed
  8. Shimano 12 speed

Chains

  1. SRAM Eagle™ all models
  2. KMC 12 speed
  3. Shimano 12 speed

Chainrings

  1. Ratio Ring
  2. 1×12 chainrings
  3. 1×11 chainrings
  4. 1×10 chainrings


1×12 Wide Forward Exit

Image credit: bikepacking.com

What’s it for?

Upgrade your SRAM 1×11 drivetrain to wide-range, mechanical 1×12 using SRAM Eagle™ components. The Forward Exit version of the kit leaves the Eagle™ derailleur cable routing unchanged, but isn’t compatible with all frame designs. For more information, check the “Forward vs. Rear Exit” section of this guide.

What’s in the kit?

The 1×12 Wide Forward Exit kit includes a 1×12 Wide ratchet for Eagle™ 12 speed indexing, a cable fin to convert Eagle™ derailleurs to Exact Actuation™ (allowing them to work with SRAM road shifters) and a cable adjuster that slots into the derailleur’s cable port.

1×12 Wide Forward Exit Compatibility:

Green – Recommended

Amber – Untested but fine in most cases

Red – Not recommended

Derailleurs

  1. SRAM Eagle ™ GX™, X01™ and XX1™
  2. SRAM Eagle™ NX™ and SX™

Shifters

  1. SRAM 11 speed road all models
  2. SRAM 10 speed road (using Ratio Cable Spool)

Cassettes

  1. SRAM Eagle™ all models
  2. e*Thirteen
  3. Garbaruk
  4. Rotor
  5. Ingrid
  6. Leonardi
  7. SRAM road AXS™ 12 speed
  8. Shimano 12 speed

Chains

  1. SRAM Eagle™ all models
  2. KMC 12 speed
  3. Shimano 12 speed

Chainrings

  1. Ratio Ring
  2. 1×12 chainrings
  3. 1×11 chainrings
  4. 1×10 chainrings


Forward vs Rear Exit

Our 1×12 Wide kits come in two flavours: Forward Exit and Rear Exit. These names refer to the direction in which the cable leaves the derailleur; SRAM Eagle derailleurs have a forward-facing cable port as standard, but this is incompatible with some road and gravel frames. We created the Rear Exit kit to help you to fit our kits to these frames. Rear Exit derailleurs are compatible with all frame designs, but importantly our Rear Exit kit can’t be fitted to GX™ derailleurs without the permanent removal of a rivet.

Forward Vs Rear Compatibility Diagrams:

Use the following diagrams to work out whether your frame is compatible with the Forward Exit kit, or whether you need Rear Exit:


Ratio Ring

What’s it for?

The Ratio Ring is a 1x-specific chainring for 12 and 13 speed drivetrains. The chainring features a directional narrow-wide profile to prevent chain drops both while pedalling and when freewheeling over rough terrain. The chainring is currently available for 5 bolt, 110 mm BCD fitment.

Ratio Ring compatibility:

The Ratio Ring is designed for use with Campagnolo Ekar™ 13 speed chains, and with SRAM Flattop™ and Eagle™ 12 speed chains. The 5 bolt, 110 BCD pattern is the most common ‘road compact’ chainset bolt pattern.


1×12 Ratchets and Cable Spool

What’s it for?

Our 12 speed ratchets allow you to keep your 11 and 10 speed shifters up-to-date with the newest drivetrain tech. Our current range of upgrade ratchets consists of the 1×12 Wide ratchet (to shift SRAM Eagle™ and similar cassettes) and the 1×12 Close ratchet (to shift SRAM road 12 speed cassettes). Check our kit compatibility above for a complete list of cassettes. Both ratchets are designed for use in SRAM’s 11 speed road shifters, but they can also be fitted to older 10 speed shifters using our replacement Cable Spool.

Ratchet compatibility:

  1. SRAM 11 speed road levers from the Red™, Force™, Rival™ or Apex™
  2. SRAM 10 speed road levers with a red-coloured cable spool (including new shape S-Series™ levers)
  3. SRAM 10 speed road levers with a Ratio cable spool fitted

The cable spool is the plastic part that holds your derailleur cable in the shifter. If it is red-coloured, you can fit our ratchet immediately; this is the case for all SRAM 11 speed road shifters and some newer ZeroLoss™ 10 speed shifters including Red™ SB-RED-B1. If the cable spool is white in colour, you’ll need to replace it with our Cable Spool in order to fit our ratchet.


Cable Fin

What’s it for?

The cable fin is the part that allows you to match up SRAM’s Eagle™ derailleurs with their road shifters. SRAM’s Eagle™ range uses their X Actuation™ standard whereas their mechanical road range uses Exact Actuation™. Fitting our cable fin to an X Actuation™ derailleur converts it to Exact Actuation™, effectively turning it into a road derailleur.

This means that you can use our cable fin on its own to pair an Eagle™ derailleur with SRAM’s 11 speed road shifters, giving you the capacity to run a wide-range 11 speed cassette such as those available from Garbaruk.

Our cable fins come with a cable adjuster: road shifters don’t have in-built adjusters so you’ll be able to index your gears at the derailleur.

The cable fin is secured with a circlip – we provide a spare in case the original makes a bid for freedom.
The Ratio barrel adjuster allows you to index at the derailleur. Ratio engineers are not usually this dirty.

Cable Fin Compatibility:

  1. SRAM Eagle™ derailleurs from the GX™, X01™ and XX1™ groups
  2. SRAM 1×11 derailleurs (only if the existing cable fin is held on with a circlip)
  3. SRAM Eagle™ derailleurs from the NX™ and SX™ groups (the cable fin on these derailleurs is not replaceable)

Rear Exit Cable Stop

What’s it for?

The Ratio Rear Exit Cable Stop replaces the cable pulley on your SRAM Eagle™ derailleur to give it road-style rear exit cable routing. The Cable Stop includes an adjuster so that you can index your gears at the derailleur.

Because you must first remove the cable pulley to fit the Rear Exit Cable Stop, this part is only compatible with Eagle™ derailleurs that use a bolted cable pulley. On lower-tier models that use a riveted cable pulley, the rivet must be removed with a 4 mm drill bit. This is a dangerous and irreversible process that we do not recommend.

The Rear Exit Cable Stop can also be fitted to older SRAM 1×11 mtb derailleurs for use on frames with road-style cable routing, but be sure to check that the cable pulley is not fitted with a rivet first.

Rear Exit Cable Stop Compatibility:

  1. SRAM Eagle™ derailleurs from the X01™ and XX1™ groups
  2. Pre-fitted SRAM Eagle™ GX™ derailleurs in a Ratio kit bundle
  3. SRAM 1×11 mtb derailleurs (check that the cable pulley is not riveted)
  4. SRAM Eagle™ derailleurs from the GX™, NX™ and SX™ groups

FAQs

Can I use an Eagle chain on a SRAM road 12 speed cassette?

No – you’ll need SRAM’s Flattop™ chain. Despite both Eagle™and Flattop™ chains being 12 speed, Eagle™ chains are wider and have standard 7.7 mm rollers instead of the Flattop™ 7.9 mm rollers. Using the wrong chain feels like you’re pedalling a bag of rocks (trust us, we’ve tried it).

Why can’t I fit the Rear Exit kit to my GX derailleur?

The Rear Exit Cable Stop replaces the cable pulley found on SRAM’s 1x mtb derailleurs. On higher-tier derailleurs, SRAM fits these with a bolt. However, on derailleurs up to and including GX™ the pulley is fitted with a rivet. To remove the pulley, the rivet must first be drilled out with a 5 mm drill bit. We don’t recommend that you try this at home; it’s a dangerous operation that could result in permanent damage to your derailleur or you!

Will there be a 2×12 Road kit?

There are a few more kits on the way, yes. We wouldn’t recommend using our 1×12 Road upgrade kit to create a 2×12 drivetrain as the jockey wheels are the wrong size for SRAM’s 2x compatible road derailleurs and the Flattop™ chain won’t play nicely with the original jockeys.

Can I use an Eagle chain on an 11 speed chainring?

Yes. If you don’t have a chainring yet then you should really choose a 12 speed model, but Eagle™ chains will generally run fine on 1×11 chainrings. The teeth on these chainrings are around 0.1 mm wider when they’re new. This is enough to reduce the mud clearance but not enough to prevent the chain engaging properly. Additionally, if your 11 speed chainring is already worn it’s highly likely that it already has the same geometry as a 12 speed model.

Can I use a Force 1™, Rival 1™ or Apex 1™ long cage rear derailleur with a 10-44t xplr™ cassette?

The listed maximum sprocket size for SRAM’s road 1x long cage derailleurs is 42t but this is quite conservative. We’ve tested the long cage derailleurs with the XPLR™ 10-44t cassettes extensively and we’re happy to recommend this combination.

Can I use a Ratio upgrade kit with a Shimano Hyperglide+ 12 speed MTB cassette?

Our upgrade kits are designed specifically for SRAM Eagle compatible cassettes. SRAM & Shimano cassettes do not have constant spacing and, in two regions of the cassette, the deviation between them is large enough to cause clicking and ghost shifting. We’ve tried this combination and although some users may find it tolerable, we believe that you should keep that OEM feel when converting to wide range 1x.

Will there be a Ratio upgrade kit for shimano sti shifters?

Shimano shifters are very difficult to disassemble and contain lots of irreversibly fixed components (permanently riveted together rather than screwed or bolted). We’d really love to make a Shimano kit but don’t see it being practically possible in the near future.