New SRAM DUB mountain bike cranksets are lighter, more durable than ever.
SRAM have announced a major revision to their mountain bike cranks and bottom brackets, a change that’s intended to increase bottom bracket longevity, as well as simplify the lineup. The revamp also allowed them to shed a significant amount of weight from the XX1 crankset, and it’s now claimed to be one of the lightest options on the market.
Called DUB (Durable Unified Bottom bracket), the most significant update is the change to a 28.99mm spindle for all mountain bike cranks. Previously, SRAM had two different spindle diameters (30mm and 24mm), along with a range of bottom bracket bearing sizes. With DUB, they now offer one spindle diameter and four bottom brackets that will fit all of the existing frame standards.
Where did that 28.99mm number come from? Why not just switch everything over to 30mm spindles and call it good? According to SRAM, their product development in San Luis Obispo, California, tried multiple configurations, beginning with the existing 30mm spindle size, before settling on what they felt offered up the ideal balance of bearing size, durability, and weight. The new bottom brackets have more seals than the previous models in order to keep contaminants like water and dirt from working their way into the bearings. Along with the improved weather sealing, SRAM has gone to metal cups on their press-fit bottom brackets, rather than the plastic cups used previously.
The following video from SRAM provides a little more insight into the concept, as well as a chance to witness some interesting Movember facial hair:
Specifications and Pricing
• XX1 Eagle: $515 – $525 | €570 – €585 | £510 – £520
• X01 Eagle: $485 – $495 | €540 – €550 | £480 – £490
• GX Eagle: $135 – $185 | €150 – €205 | £135 – £185
• Descendant Carbon DUB: $260 | €290 | £255
• Descendant 6K DUB: $105 | €115 | £105
• Stylo Carbon: $260 – $310 | €290 – €345 | £255 – £305
• Truvativ Stylo 6k: $105 | €115 | £105
• Bottom brackets: $38 – $50 | €38 – €52 | £32 – £44