Ridiculously light carbon fibre XC wheels
In this age of ever more durable, enduro-ready gear, it’s totally out of fashion to shout about lightweight components and how much difference they make to ride quality. Indeed, it’s at the burlier end of the spectrum where you’ll find our best mountain bike wheels to date.
But a weight saving is especially important for wheels, where the effects of rotating mass means lighter hoops amplify weight savings, reduce unsprung mass, and make bikes easier to accelerate, decelerate and change direction.
One of the cheapest ways to test this theory is by bolting on something like these ridiculously light £800 Silt XC carbon wheels. That much money for sub 1,400g wheelset is amazing value, and Silt’s latest offering also comes with proven components and an unlimited free crash replacement programme (labour not included).
The XC rims at the heart of the weight saving are 27mm wide internally; thinner than the brand’s AMs, but plenty wide enough for appropriate tyres. They use ‘reinforced’ carbon, which describes higher modulus (more brittle) base fibres with extra material around spoke holes layered with harder to dent/chip finishing fibres on top (rather than any mesh or embedded glass fibre). Rims are drilled at an angle, so spokes point more accurately at the angled flanges on Silt’s Ratchet Drive hubs too.
Silt’s spring-loaded freehub has a heat-treated stainless steel drive ring similar to DT Swiss, albeit with a leaf (rather than cylindrical spring) behind. Pick up is fast and spares are cheap and easy to fit. The system has a loud whine, which might be too much for some tastes, but mechanically it’s been totally solid on all the Silt wheels I’ve tested.
Spokes are superlight bladed/butted Pillar PSR XTRAs that are under 5g each, aero for extra rolling speed and held by alloy nipples. 28 at each wheel are laced two-cross for further weight saving and extra spokes, nipples and tubeless valves are included in the box.
Unless your wheels are already flyweight, you’ll immediately notice just how much difference light hoops like these make. They save around 500g over most typical trail wheels, which results in a noticeable extra surge forward with each pedal stroke, and it’s much quicker to reach the speed where rolling momentum takes a bigger effect. Overall average speeds are noticeably higher, particularly when climbing steep hills, and it’s way easier to turn over each wheel revolution, so the bike ‘pulses’ uphill and saves energy. Even with knackered legs, there’s little sense of ever dragging yourself around on the Silt XC carbons.
A further big advantage on top of this free speed, is how much more dynamic the bike feels; suspension at both ends is livelier and tracks bumps and uneven terrain better, plus Silt’s wheels also slow down rapidly, so you can brake later for beaten up berm entrances than on momentum-laden 2kg-plus wheels that just want to keep on trucking. In turns of turning and manoeuvrability, the difference is night and day. Equally, it’s so much easier to change direction and steer accurately, that it makes modern, long, low, slack 29ers feel flickable and fun.
I did have a couple of issues though; one with the freehub being sticky out of the box (that was easy to fix) and the front hub spacer also fell off multiple times; potentially annoying for car users removing the front wheel to load. (I’ve not had this issue on Silt wheels before, to be fair).
So, light wheels are fantastic, and this review has reminded me they’re one of the ultimate upgrades to transform the feel of your bike, but how do Silt’s compare to other lightweight rivals?
Obviously, the low price is a major draw, but there’s also snappy immediacy and proper stomp-and-go acceleration that sees you soon zipping along. Even with the relatively shallow 25mm rim depth, the ride is less conforming and damped than some more expensive carbon wheels I’ve tested, more like old-fashioned razor-sharp carbon XC wheels. This harshness isn’t excessive, but just a sense of a bit more feedback and vibration from small rocks flecked in the ground, rather than smoothing out every ripple like some modern rims that are designed to specifically create extra compliance.
Silt’s wheels aren’t just light either, they seem plenty tough. I also fitted beefier tyres and plugged them into a 150mm bike to hammer them harder than intended on rocky tracks. After experiencing some serious clangs and bangs, I’ve concluded that unless you’re a really heavy clumsy rider you shouldn’t be needing the crash replacement programme for regular XC and trail riding.
Silt’s XC wheels are well sorted and bring all the benefits of a lightweight wheelset, albeit with a slightly sharper ride than some carbon options. The closest category rivals I can think of are Specialized’s carbon Roval Controls that are around 100g heavier and also £350 more expensive. In terms of value and performance then, the Silt Carbon XC wheels are impressive.