Power
Judging a brake’s power is subjective, and it’s made more challenging with the variety of varying factors like rotor size, the bike you happen to be on, trail conditions, and tire choice. Even so, comparing the Afterburners to some of the current high-end offerings from Shimano and SRAM, I’d say they’re a little less powerful, but I would not call them underpowered.
I’ve tested the Afterburners with a 180mm front and 160mm rear rotor on my hardtail Canfield Yelli Screamy, which is the same setup that I used to test the Avid Elixir 9 Trails. In terms of stopping power, the Afterburners felt comparable to the Elixirs, and, again, a bit less powerful than the SRAM Guide RSC (which I tested on my Specialized Enduro), but not bad by any means.
It’s worth noting that the largest rotor size FSA makes is 180mm; you can’t buy a 200mm rotor for either the K-Force or Afterburner. Running a 180mm rotor wasn’t a problem for me on my hardtail, but I generally run a 200mm rotor on the front of my trail / all mountain bike. (Theoretically, I might be able to use some other company’s 200mm rotor, but it doesn’t appear that FSA makes a mounting adaptor for the larger rotor size.)
I’m not sure why FSA wouldn’t offer a 200mm rotor option While this brake probably doesn’t offer the power you’d want for a full-on DH bike, I think a lot of people would be happy running the Afterburners with big, 200mm rotors on a trail bike.
Modulation
Modulation is talked about a lot in the world of disc brakes, and for good reason. If the only thing a brake can do is lock up the wheels on your bike, it’s not a very good brake. Stopping power is good, but the more usable that power is, the better.
FSA designed the Afterburner’s lever to deliver stopping power through the brakes in a very linear fashion. This is different from Shimano’s Servo Wave and SRAM’s Swinglink levers, both of which offer a less linear, more progressive pull. There are some advantages to SRAM and Shimano’s designs. For example, the lever can be made to move the brake pads a lot at the beginning of the stroke (closing the gap between the rotor and the pad quickly), while offering a more gradual increase in power later/deeper in the lever stroke. These designs work very well and offer great power, but they take a little getting used to.
The more linear feel of the Afterburners is a bit more intuitive; I didn’t feel like I had to “learn” the lever. I don’t particularly like “soft” brakes, and the Afterburner levers have an even, relatively firm feel that’s right up my alley. The brake levers have enough ‘give’ that you can get the modulation you need out of them without having a mushy, bottomless feel.
Pump-out
Despite the fact that these brakes were on my hardtail, I still took them out for some lift-served laps, and a few extended descents where I got them good and hot. I noticed that the Afterburners pumped-out a little bit when they warmed up, but I wouldn’t say they were out of line with most other brakes on the market. If I wanted, I think I could help these brakes produce less heat and dissipate it better by (1) swapping to a larger rotor in the rear, (2) running Shimano Ice Tech pads, and (3) switching to the rotors used on the FSA K-Force brakes, which feature an aluminum carrier body.
Apart from the relatively minor pump I noticed when the Afterburners got hot, they’ve worked flawlessly. I haven’t had to re-bleed or mess with the brakes in any way since the initial install (which is expected, since I’ve only been riding them for a bit over a month), and they have stayed nice and quiet. I have found that there is a bit of slop in the levers’ pivot bushings, allowing the blades to rattle around a bit. I don’t notice this at all once speeds pick up, but it can be a little distracting on fire road climbs.
Price (Updated)
When I first wrote this piece, the Afterburners were priced at $290 per brake, which put them thoroughly in the territory of high zoot, pretty damn expensive brakes. Originally I mentioned that I would have had a hard time justifying that price tag, even though when it came to performance and feel alone, for use on a trail or XC bike like my Canfield hardtail, I prefered the Afterburners to the SRAM Guide RSC. (I like the Afterburner’s lever feel and shape better.) However, late last fall, FSA brought the price own to a far more reasonable $200 per brake, which is more-or-less in line with a number of other brakes on the market (like the Guide RSC). The Afterburners are now fairly competitive in terms of their price tag, in addition to their performance, and that, of course, is a good thing.
Durability (Updated)
I now have a bit more time on the Afterburners, and the good news is, I have nothing more to report with respect to their durability. No durability issues have surfaced, and everything I said about their performance still stands. Getting back on them after a brief hiatus (a minor hiccup we refer to as “winter” in Montana), the only thing I’ve notices is that the lever blades have a bit of a rattle to them. It’s something I noted initially in my review, and it’s still an occasional annoyance.
Bottom Line
The FSA Afterburners aren’t the most powerful brakes on the market, but they’re no longer prohibitively expensive, and for the price they offer fantastic lever feel and great stopping power for XC and trail bikes.
After smoking (warped) some old XTR rotors this summer on a 30 minute long steep winding descent, I switched to the Freeza RT-99s and finned pads. Great upgrade for steep descending. On an actual downhill course though, I am on the brakes as little as possible, so possibly overkill.
Were you using FSA’s mineral oil for bleeding? Or did you use Shimano?