The 45T X-Cog upgrade increases the stock Shimano 11-speed 11-40 cassette range by 12.5%. The 45T provides more total cassette range, it’s not just an easier granny gear. Adding the OneUp 45T X-Cog lets you increase your 1x11 front chainring from a 30T to 34T without losing any low range. Eliminate dropped chains forever with our true narrow-wide chainring design. This cog tunes the cassette progression into two distinct zones optimized for climbing and descending.
Climbing: (21-45T) 13-15% cassette progression. Smaller jumps to maintain an optimum even climbing cadence.
Descending: (11-18T) 15-20% cassette progression. Larger jumps to reduce double tap shifting and provide faster burst acceleration when mainly pumping not spinning down trails.
- 18T sprocket provides more even cassette progression for smoother cadence and improved shifting
- Maintains the 40T as the smallest alloy sprocket for maximum cassette durability
- Compatible with M9000/M8000 GS and SGS derailleurs, and XT M8000 or XTR M9000 cassettes only
- Compatible with standard freehub driver bodies
- 10 upshift points
- Cassette progression: 11-13-15-18-21-24-27-31-35-40-45
- Adds only 65 grams to stock XT or XTR cassette