In this edition of Ask a Wrench, pulled from the members-only segment of the Geek Warning podcast (May 29, 2025 episode), tech editor Dave Rome and pro mechanic Brad Copeland take on three listener questions. They cover future-proofing SRAM 11-speed rim brake bikes, whether there’s a trail-style geometry number for rear-end handling, and how to travel smart with a SRAM Transmission derailleur that requires 35 Nm torque.
Geek Warning is tailored for riders who love to tweak, tune, and push their setups. Questions and answers have been edited for length and clarity, so if you want the full nuance and discussion, you can listen to the complete members-only episode embedded below the paywall down at the bottom of this post.
Q1: What are my options for replacing aging SRAM 11-speed rim-brake groupsets with SRAM-like alternatives?
From: Johan in Kuala Lumpur, Malaysia
Brad Copeland: There’s some useful compatibility between current SRAM AXS components and older 11-speed eTap parts. To an extent you can often create multi-generational blends – for example, using a newer shifter with an older rear derailleur – though that doesn’t apply to every component. The original eTap groupset was short-lived, so spares may become harder to find.
The bigger issue in the long term is rim brake support. Groupsets are increasingly focused on disc brakes, and newer drivetrain innovations assume that platform. Stocking up on rim brake-compatible shifters in particular is a smart idea.
Also consider your bikes’ standards – things like quick-release axles and rim brakes are becoming less common. That’s another layer of incompatibility to be aware of going forward.
If you’re committed to keeping these bikes going, especially with period-correct builds, it’s a good idea to buy key parts now – like rear derailleurs or other model-specific items – while they’re still available. That’s something I do for my own vintage bikes.
Dave Rome: SRAM still makes 12-speed eTap rim brake shifters that are compatible with the original A1 Red eTap 11-speed front and rear derailleurs. SRAM also makes a Red A2 eTap rear derailleur should you need a new rear derailleur. The limitation is in the front derailleur – the original 11-speed versions are discontinued, and newer 12-speed AXS front derailleurs can't be paired with older 11-speed rear derailleurs. All is good until you need that front derailleur.
Also worth mentioning – wear components like chains, cassettes, and chainrings are easy. SRAM 11-speed was very cross-compatible with Shimano and others, so sourcing those parts will not be a problem. It’s the proprietary electronic or mechanical parts you’ll want to secure while they’re still around.
Q2: Is there a single number we can use to understand rear-end bike handling, similar to the trail figure for the front?
Did we do a good job with this story?
