Small part, big surprise: SRAM Red derailleur pulleys are expensive!

I realized this year that my slow and steady journey to cremation and freedom can be measured by my bike’s gear ratio. Back when I was full of youth and raced the flat criteriums in NYC I ran a 52-39 crankset with an 11-22 cassette. As I began to venture further out of the city my default cassette grew to an 11-28. When I moved to a hillier area my crankset was replaced with a compact 34-50 for climbing. This most recent chapter of RideWithGPS-powered centuries has broken me down even further and I finally downshifted to an 11-32 cassette.

This last jump required not only a new cassette and longer chain but also a new derailleur as my first-gen eTap Red short cage only ran up to a 28t cog. So off to eBay I went to find a first-gen SRAM eTap “WiFLi” rear derailleur.

When fishing for parts on eBay you have two choices: be patient and wait for “the one”, or grab something “close enough” and fix what you need to. With a big hilly ride rapidly approaching, I opted for the latter. I found a unit that was in perfect cosmetic condition but had worn-out aftermarket pulleys. No big deal, I thought–I’ll just hop back on the Internet and get some cheap replacements. They looked like your typical $30 nylon affair.

Boy, was I wrong!

As I jumped from site to site, I noticed that most online listings for pulleys mentioned SRAM Force but not SRAM Red. After purchasing the cheaper Force pulleys thinking I could save a few bucks, they turned out to NOT be compatible with the Red derailleur. The Red derailleur has two different pulley axle diameters, which ensures that only Red pulleys are used.

After scouring the Red groupset parts guide I figured it out:

The first-gen SRAM RED eTap Rear Derailleur is MODEL ID: RD-RED-E-A1

It requires OEM SRAM AeroGlide Ceramic Pulleys
MPN: 11.7518.066.000
UPC: 710845782121

These plain-ass looking mothers retail for $161! This price vs. appearance discrepancy is like that one guy who put a 350-horsepower turbocharged engine in his minivan. These are the most ordinary-looking high-performance anything I’ve ever seen. It breaks my brain.

With no other real options, I went ahead and bought them. Here they are in all their glory. Rawr:

SRAM Red eTap derailleur pulleys in box

And here they are dressed up on a plate of fancy cookies for no reason:

There isn’t much to say in terms of a review. Since these are OEM parts they fit perfectly, shift crisply, and make the drivetrain purr like new. Which I would hope they would do for the price. They won’t turn any heads. Not a single one. Which I guess I’m also okay with. I was just surprised that this was so much work to (1) figure out the upgrade path from 28 to 32t and (2) find the part number in stock at a retailer I could purchase from.

If you’re looking to upgrade a first-gen SRAM eTap short cage derailleur setup from a 28t cassette to a 32t cassette, these are the questions and answers you’ll go through: (My path was much longer with many dead-ends. When you have the right answers it’s a pretty quick explanation!

Can I add a longer cage to my SRAM eTap Red derailleur to accommodate larger gears?

No. This article is buried deep in Google for some reason, but according to SRAM:

There are more differences between a standard eTap rear derailleur and a WiFLi eTap rear derailleur than just the cage length.

In addition to the longer length of the cage on the eTap WiFLi rear derailleur, the position of the upper pulley is different as well. On a standard short-cage eTap rear derailleur the upper pulley is concentric with the cage’s pivot; whereas on a WiFLi eTap rear derailleur, the upper pulley is offset to provide greater clearance between the pulley and the cassette.

The other big difference is that the WiFLi eTap rear derailleur mounting bolt is positioned both higher and further rearward than it is on the standard short cage eTap rear derailleur. This positions the rear derailleur lower down and further forward in relation to the cassette and generates increased clearance between the upper derailleur pulley and cassettes with big cogs as large as 32-teeth. For this reason, simply installing a long WiFLi pulley cage onto a standard eTap rear derailleur will not make it compatible with cogs larger than 28-teeth.

Can I buy SRAM Force pulleys instead of SRAM Red pulleys to save a little money?

No! The top pulley axle on the Reds is smaller than on the Force, so the bolt will not fit correctly.

Can I buy third-party pulleys to save a little money?

Yes BUT… if you have a first-gen eTap Red derailleur, you need to buy pulleys that very specifically mention compatibility with first-gen eTap Red derailleurs. As the question above addressed, other models of pulley have different sized bearing axles and will not fit in your derailleur.

Do I need to grease my new SRAM eTap Red derailleur pulleys before their first use?

No. According to SRAM customer support

“The grease is for later use, the pulleys are ready to go. If you need guidance on how to service the pulleys, at this time we do not have official manuals, but you can follow the same procedure that is used in this video.”

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