When choosing the right crank combination, it's all about the right mountain gear and the desired gear range. With a choice of 26 to 40 teeth in three price segments, Sram is clearly ahead when it comes to 1x. The differences between the 2x cranks are small. One small drawback for 29er riders is that Shimano doesn't offer a version with a 22 t chainring. For 3x we clearly recommend Shimano. Firstly because of the more usable gear ratios - the 44 t chainring from Sram is only useful to a limited extent - and secondly because the centre chainring made of composite materials from Deore to XT combines high durability with low weight. Sram relies on aluminium throughout. The fact that Shimano only offers aluminium cranks and Sram's top groupsets are made of carbon is more a question of image.
For frequent riders, it is worth opting for the heavier but cheaper and more durable steel chainrings for the small and medium chainrings. Standard on Shimano SLX and Deore.
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