Review: Avid Shorty Ultimate cantilever brakes
Avid’s Shorty Ultimate offers a choice of wide- and low-profile configurations in one cantilever brake. The cable arm and brake block post are separate components clamped together by twin hex bolts via one of the two pairs of holes that provide the alternative setups.
One arm houses a cable adjuster, the other the straddle cable clamp. The brake uses a simple straddle wire with stirrup rather than a Shimano-type link wire. The Ultimate uses replaceable Shimano-pattern road brake blocks in shoes that can be adjusted for toe-in and to match the rim’s brake track angle.
The retracting springs engage with bosses clamped to the spigots. These can be turned using a 15mm spanner, once the fixing bolts have been slackened, to ensure precise centring of the blocks.
Avid claims 20% greater power in the low-profile configuration. My test rides backed this up. In wide mode, the brake has a harder feel at the lever, which is indicative of a lower mechanical advantage and less power.
The Shorty Ultimate is a clever-looking design but not without issues. It seems designed for a 19mm wide rim. Mounted on spigots at 80mm spacing, the brake’s blocks can be angled to meet a 22mm wide rim correctly, but on a 24mm rim the washer system does not allow enough articulation.
In low-profile mode, the outboard washer fouls the arm when positioned near the bottom of the slot, limiting height adjustment. The washers can’t be swapped to accommodate rim width as the outer one won’t pass over the shoe mounting post.
The adjuster barrel is drilled for the 1.5mm diameter straddle wire provided. A standard 1.6mm brake cable won’t pass through and spares don’t appear to be widely available.
Perhaps the Ultimate’s designer missed a trick. The shoe post section is offset towards the rim from the spigot centreline but by so much that it can’t be reversed to offer more clearance. A little attention here would make the brake the versatile design it aims to be.
Lightweight at 120g per wheel but expensive, complex and supplied with an unusual straddle cable, the Ultimate works well in low-profile mode on a rim of suitable width.
Tektro CR720 £23 each
Chunky-looking but highly effective low-profile design with loads of adjustability.