FSA SL-K BB392-EVO Modular Crankset review
The SL-K 392 EVO is the newest modular crankset from component maker Full Speed Ahead.
What is it
If you’re looking for a crankset for your next cross-country or enduro race build, the FSA SL-K-392 EVO Modular belongs on your short list. FSA launched its first modular crankset in 2016, and updated it this season with the SL-K EVO 392 Modular. While the name can be confusing, the crankset is straightforward, easy to install, and very compatible.
Weighing a respectable 485 grams (crank arms, chain ring, spindle) this crankset will shave grams off most stock XC rig builds. Just make sure you know and understand the bottom bracket size and style on your bike, as the compatible nature of the SL-K EVO can take newcomers by surprise. Competent mechanics will find the single-ring SL-K EVO format easy to work with and compatible with many different brands and styles.
The SL-K EVO can be adapted to fit most frames and riding styles, all you need is the right spacers.
Double ring users will find a new BCD with the SL-K EVO and could have a difficult time finding rings at your local bike shop. But the SL-K EVO is competitive with the newest and lightest on the market and worth the price for adding some stiffness and style to your new race machine.
Key features include a convertible spider design for different chaining and chain line configurations, hollow carbon composite arms with UD finish, 30mm forged spindle, 100% CNC’d chainrings (sizes 28-34), and FSA-Mega-Tooth thick-thin tooth design for enhanced chain engagement.
Pros
- Reasonable price
- Works with all BB types with the right bottom bracket configuration
- Light enough for XC, strong enough for trail riding
- Comes with tools
- Single and double chain ring options
- Clean, precise shifting with 2x set-up
- Compatible with other manufacture’s designs
- Chain line manipulation for single speed usage
- Self-extracting crank arm on drive side
Cons
- BB392 adaption for some frames is a pain
- Proprietary BCD for double ring set-up
- Requires aftermarket shims for anything not BB392
- Lock ring can be difficult to get to torque spec
- Non-interchangeable spindle length (Note: 83mm and 100m spindles now available)
- Carbon arms abrade easily (Note: boots now available)
Mtbr’s Take
It can be hard to tell if a certain part like a crankset is going to make a notable impact on your ride and give you a performance advantage. The FSA SL-K EVO is a crankset that can help you find that distinction with beefy carbon arms, ease of installation, and adaptability.
Unidirectional-hollow carbon crankarms make for a light and eye-catching crank.
For FSA the SL-K line is the working man’s racing component, something that will be light enough to compete with the fastest, but won’t empty your post-race beer fund. The SL-K EVO can fit virtually any frame.
Hollow unidirectional carbon arms and an alloy spindle make up the bulk of the FSA SL-K EVO construction. This leads to a very light and stiff crankset, something that can be felt when switching from a lower quality alloy crankset. The hollow carbon arms are a mainstay for FSA’s top-tier road components and have trickled down to the SL-K and other carbon components it produces. In Mtbr’s case, the FSA SL-K EVO shaved 100 grams off our test bike.
After the original bottom bracket wore out, we switched to a Race Face Cinch style.
For our tests, the FSA-SL-K EVO was installed on a 2017 Trek Top Fuel that previously was spec’d with a SRAM XX1 carbon crankset. The Trek Top Fuel frameset has a PF92 bottom bracket, which works well with 24mm SRAM and Shimano cranks but requires an aftermarket bottom bracket from FSA to adapt the 30mm spindle to the PF92 shell.
For the bottom bracket FSA supplied a BB392-BB89.5/92MM kit that sized down the bearings, allowing the 30mm spindle to be installed in a 92mm shell. Installation was quick and easy: press in the bearings, add spacers to the spindle, install the crank arms, torque to spec with no shims needed (although we did check for play and re-torqued after the initial ride to make sure everything was still tight).
Self extracting crankarms are not new but they are happily welcomed in the world of modular cranks. No more crankarm pullers and small bits to lose.
On the trail the crankset performed as expected, with zero dropped chains and no mysterious noises coming from the bottom bracket.
It’s hard to tell if the crank added any stiffness to the ride, but they certainly give the look of stiffness and power. The crank arms are sleek and wide, at least conveying a sense of strength and full power efficiency.
On the downside, I had some pedal strikes during testing and noticed the carbon abraded very easily. This is something that can be solved with boot style-covers, but none are provided. The full-arm finish protectors did guard against shoe rub and interference, but after many rides and washes they have come off.
After many miles the SL-K chainring had not dropped a chain, even though the ring was visibly worn.
Ride after ride, up and down mountains, the FSA SL-K EVO Crankset has not made a creek, pop or squeak, sounds that are commonplace among most modular. Chalk this up to the construction and two-piece crank arm design. The BB92 adapted bottom bracket, however, did need replacing within the first two months of testing. This could be from my bike washing habits, or smaller bearings in the bottom bracket and a non-PF30 specific frame could be causing the bearings to wear faster.
Bottom line the FSA SL-K EVO Modular crankset is a great upgrade, and the chameleon like nature makes it a smart choice that will transfer from bike to bike.
Rating: 4 out of 5 
Price: $445 (crankset and 32T ring)
More info: shop.fullspeedahead.com
The post FSA SL-K BB392-EVO Modular Crankset review appeared first on Mountain Bike Review.