While better known for its cranks and finishing kit, FSA has recently enjoyed great success with it’s high end Vision road wheels. Ridden by the likes of Peter Sagan in the TdF, and to even more impressive heights by famed trials rider Martyn Ashton, FSA felt they could leverage that technology to create a feature rich off-road product.
They have divided the product line into three distinct models, which are versatile enough to encompass several dissimilar but related cycling disciplines – everything from gravel, CX, to XC and trail.
All three wheel sets share an offset asymmetric rim design. Many companies have experimented with asymmetric rims, but FSA has taken the design one step further. Rather than the more common 2mm offset, they’ve used a 4mm. The main benefit of this deign is improved spoke tension balance.
On regular rims, the spokes on one side of the wheels are always providing more tension than the other. With an asymmetric offset there is better triangulation of the spokes, which narrows the difference between the spoke tensions, and allows the wheels to brought to a higher tension overall. This offers increased lateral stiffness, rigidity, and durability.
As an added side benefit, FSA has also found they can run fewer spokes for decreased weight without sacrificing performance. So rather than your standard 32 h setup, these wheels utilize 24 spokes front and rear.
Each wheel set utilizes FSA hubs, with direct pull spokes. Aftermarket wheel sets will ship with various end caps, in order to make the wheel sets compatible with QR, 100×15, 135×9, and 142×12.
Inside, the hubs have six pawls working in conjunction with a 27 tooth ratchet ring. As the free hub spins, three of the pawls are always engaged. This arrangement is durable and offers quick engagement (54 POE or 6.6 degrees of engagement).
The top of the line K-Force wheels receive ceramic bearings, while the carbon SLK wheels, and alloy Afterburner wheelset both spin on stainless steel bearings.
A preload system, borrowed for their Vision road wheels, allows you to adjust the bearings for improved bearing life and a faster spinning wheel. FSA claims this is an important feature because regardless of manufacturer, being able to adjust for small tolerance variations offers better bearing performance – which equates to free speed.
All of the wheels are 100% hand built (lacing, truing, tensioning, etc.. ).
The K-Force and SLK wheel sets share the same carbon rim, which has a 26mm external, and a 21 mm internal measurement, but utilize different bearings, spokes, and nipples. The difference between the two is $250 and 36 g.
On the budget side, the Afterburner rims share the same rim profile, but utilize aluminum hoops. Retail will be $649.99. The wheel sets will begin shipping on OE bikes beginning Q1 next year, and will be available soon after through distributors and IBDs.