It would've been easy for the engineers at Race Face to sit back and relax for a while after the release of the Next SL, surveying their line of lithe carbon componentry with pride and satisfied nods of approval. We're glad to say that they chose not to do this, and because of it, the gram-conscious world of XC and trail riding can continue to benefit from the brand's persistent quest for improvement. This year, that overachieving spirit has left us with the updated Race Face Next SL G4 Crank Arms, which manage to achieve the elusive industry-wide goal of being both lighter and stiffer than their predecessors through smart construction and an effective choice in materials. Race Face didn't leave itself much room for improvement when it introduced its top-of-the-line Next SL last year, so for the most part, the brand let the effective design of the Next SL stand relatively unchanged. It continues to trust the same hollow carbon arm construction, reshaping the slim arms only slightly to integrate with the redesigned Next Direct Mount chainrings. This process ended up shaving six claimed grams per arm from last year's weight. Anticipating the demands of one-by setups, Race Face also improved the system's lateral stiffness so it can better withstand the chain tension at acute angles that it's likely to experience regularly. It did this by using Super Alloy, a metal that boasts up to a 20% increase in strength compared to the venerable 7050 aluminum, in the spline interface. To offset the weight that this could've added to the setup, it then drilled out the end of the 30mm spindle, removing unnecessary material and saving four more claimed grams in the process. As with the Next SL, the G4 continues to use Race Face's innovative Cinch system, allowing you to switch between one-by direct-mount chainrings or use a removable spider to run a double or triple setup if you swap bikes or change your mind.