Looking for extra low gearing on your Shimano road bike and frustrated by the lack of quality options? The Wolf Tooth Tanpan is a new product that will finally enable riders using Shimano road components to get ultra- low gearing on their bikes effectively and without using esoteric compromised mixes of components.

We have received many inquiries from Shimano riders asking whether it is possible for them to get lower gearing. For Di2 bikes, we have a good solution in the form of the K-Edge derailleur conversion that will adapt the Di2 rear derailleur to work with an 11-36 cassette. However, for those with cable-actuated Shimano drivetrains were limited to a 30 tooth low gear for 10 speed riders while 11 speed users could go to a 32 tooth low with use of a GS derailleur. While items like the Wolf Tooth RoadLink sometimes expanded the range of a derailleur, it wasn’t a consistent solution for all frames and drivetrains and still wasn’t low enough for many folks.

What about just installing a mountain bike derailleur to your 10 speed or 11 speed Shimano drivetrain to allow for a bigger cassette? You used to be able to make this work with a Shimano 9 speed pre-Shadow rear derailleur and 10 speed shifters, with a little rejiggering of how the cable attached to the rear derailleur. However, since Shimano went with the Shadow rear derailleur design, and now Shadow+, this has not worked well at all. Oh, it could be made to work okay at some points on the cassette, but it would then work poorly elsewhere. If you are good with inconsistent shifting at best, you can go that route, but I wouldn’t be satisfied with the result personally.

Thankfully though, there now appears to be a true solution in the Wolf Tooth Tanpan. The Wolf Tooth Tanpan changes the cable pull ratio, so that the road shifters can now work with Shimano mountain bike rear derailleurs, preferably the latest Shadow+ design. The Wolf Tooth Tanpan works in a fashion similar to that of a brake “travel agent”, used to adapt short pull brake levers to long pull cantilever brakes calipers many years ago. The Tanpan alone will allow you to use a Shimano Shadow+ rear derailleur with your Shimano road shifters and thus 11-36, 11-40, and even 11-42 cassettes become possibilities on your Shimano equipped road bike, all while keeping your double chainring crankset.

The Wolf Tooth Tanpan will be available at the end of March for a very reasonable $40. If you have been longing for lower gearing on your bike equipped with a 10 or 11 speed Shimano mechanical drivetrain, we now have the answer for you. Stop in or contact us for more information.

• About the Author

About Jim

After almost thirty years as an attorney, Jim became the service manager at Fit Werx in Vermont. He held this post for almost ten years. Having retired in 2019, Jim still likes riding, working on and writing about bikes and bike equipment.