Sitting in the middle of Specialized’s S-Works performance tyre range is this evolved Low Knob (LK) racer. At 533g it’s light and responsive with a large enough carcass to carry speed through rocks without wincing, and it’s tubeless-ready as standard.
Chopping knob height down by 30 percent from the original Fast Trak liberates rolling speed, although it still gets left behind by the fastest tyres.
The skinny tread ribs use a 65 duro centre/60 duro shoulder which grips well enough in loose or soft conditions but can twist and skate off line suddenly on damp or polished wood and rocks in race situations.
It’s a lot more supple than the cheaper Control and Armadillo puncture-proof versions, but is still stiff and plasticky in feel. This all translates to a slightly clattery, slippery and less than trustworthy feel even if you drop well below the high recommended pressure. 2Bliss tubeless readiness is useful though and it lasts well for such a light tyre.