Renthal – Renthal Rear Sprockets - Yamaha - Other, including 99-20 YZ125-250F, YZ400-450 sprockets that also cover the 88-89 Honda XR250R, purple 49P grooved options for 99+ YZ 125-250 and YZF250-450, hard anodized 520 LTD sprockets, and 525 pitch gearing for the 2025 YZF-R9 and 20-24 XTZ 690 Tenere. It is the mixed bag of the Yamaha lineup, spanning older motocross fitments, limited-edition anodized colors and newer street and adventure models that use 525 chain. Grooved and hard anodized construction both appear, and both exist for the same reason: to keep tooth form accurate under load so chain tension does not drift and power reaches the ground without slop. On the dirt side, 48P and 49P ratios favor drive and traction; on the Tenere and YZF-R9, a 46P keeps roll-on strong without making the engine buzz at cruising speed. Machined from high-grade aluminium and finished for corrosion resistance, these sprockets cut rotating weight, run quietly and hold up to the mileage adventure and street riders actually put in. Choosing the right rear sprocket is still the simplest way to make a Yamaha feel matched to the terrain it actually sees.