Review: Lightweight Avid BB7 SL Mechanical Disc Brake Calipers
After reviewing the Hayes CX5, people asked how they compared to some of the other mechanical disc brake options out there. So, we requested a few things to test, and Avid’s new BB7 SL calipers were the first to arrive. As fate would have it, they got here just in time for our NC cyclocross series finals, which was covered in snow, mud and crud. In other words, perfect testing conditions.
Introduced last year (but spotted before hand at Eurobike), Avid’s BB7 SL replace some of the steel hardware with titanium to bring the weight down, and they get a nice dark metallic “Falcon Gray” finish to set them apart…and match up with the new Red group. Functionally, they’re the same as standard Road BB7 brakes, which I’ve had
Weight savings, claimed at 25g per caliper, primarily come from using titanium hardware, better rotors and different brake pads that aluminum backed with a lightweight organic material, versus a standard metal backed sintered pad on the regular BB7 Road.
At a minimum, you’re going to be installing the three parts above: Caliper (159g), mounting bolts with their “Tri-Align Caliper Positioning System” washers (16g) and the inline barrel adjuster (4g). Total is 179g.
You’ll also need a rotor, and the BB7 SL’s ship with the newer HS1 rotors introduced in 2011 with the updated Elixir hydraulic brakes. They’re available in 140, 160, 180 and 200mm sizes. Weights for the 160 is 96g and 140 is 80g. Included bolts are 7g per rotor. I ran both 160′s, so total for the test was 206g. Standard BB7 brakes get the older Clean Sweep rotors.
Other stuff you may need depending on your bike’s set up are mounting adapters. The included adapters for front (18g), rear (13g) and bolts (10g, x2 if you needed both adapters) would add 51g to the bike. I needed the rear only since ENVE’s disc ‘cross fork is designed around a 160mm rotor.
FEATURES & PERFORMANCE
The BB7′s benefit from dual contact adjustment knobs (one on each side, for each pad). This helps get the pads as close to the rotor as possible without having to use up cable pull by twisting the inline barrel adjusters. That said, I found getting worthy performance from the brakes meant setting them up with no slack in the line. That meant closing down the barrels almost to their shortest position, pulling the cable taut with a third-hand tool, then clamping it down and using the barrel to ensure tightness. After setting the cable tension, then I’d fiddle with the knobs to bring the pads in. Ultimately, I’d put them about 1mm to 1.5mm off the rotor on either side, which provided clearance for any wobble in the rotor and a good feel at the brake lever.
The result was having the barrel adjuster in the middle of its travel, giving me full range of arm pull on the caliper, instant movement when I pulled the lever and plenty of modulation and leverage to go from feathering to lock up. It also allowed room for quick adjustments while riding.
The pad adjustment knob on the inside is huge and easy to turn even with full finger winter gloves. Compared to the Hayes’, you get the convenience of tool-free adjustments. The downside is that the adjustments are indented into fixed increments, and yes, sometimes it’ll seem like it’s either too far or too close to the rotor, particularly on the inside pad. With the Hayes brake, you need an allen wrench, but you can adjust it as much or as little as you want.
Avid recommends installing the inline barrel adjuster. Unlike the Hayes CX5, Avid’s doesn’t have a barrel adjuster built into the caliper. While there’s something to be said for all-in-one packaging, being able to adjust while riding is nice, too.
Now, let us have a moment of silence for the death of Gore cables, they will be missed.
I was fortunate enough to start the day’s race in the first wave, and conditions were still slick and dirty. It only deteriorated from there. After seeing the mud collection from the UCI cyclocross worlds, disc brakes just keep looking better and better, and these performed well.
About my set up: I used these calipers with Shimano Ultegra drop bar road levers and they worked flawlessly. Oddly, I rode a Specialized Crux Disc last summer with a full SRAM/Avid set up and, despite a lot of fiddling, couldn’t get them to feel very powerful…to the point where I opted to race the canti version of the bike for that weekend. But, Joseph has been riding the Crux Disc we’ve had in for review with SRAM Apex for a long time now with no complaints. So, two out of three, with the two being longer term, more in depth usage, have been pretty positive. I’m really happy with the stopping power and modulation. The fact that they’re so light is pure bonus.
Retail is $170 per wheel.