Drivetrain› Belt and Chain Drive
Renthal
Renthal 06-23 Yamaha YFM250/700 Raptor/ YFZ450/R Rear Grooved Sprocket - Silver 520-40 Teeth
SKU: R0A9 437U-520-40GBSI
Beginner — under 30 min
Description
Part #: 437U-520-40GBSI
Renthal UltraLight Rear Chainwheels are CNC machined from 7075 T6 aluminum to extremely tight tolerances, 66% lighter than steel. Computer engineered and tested to ensure a precise fitment, concentricity and load dispersion with tooth profiling to provide maximum power transfer. A combination of high strength base material, cutting edge manufacturing methods and exceptional hardwearing surface treatments its clear to see why Renthal's light weight all aluminum rear sprockets can be found on the rear wheels of many factory race team machines.
Chainwheel Sprockets Rear 40-Tooth
MIA's Description
Fitment
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Specifications
| Brand | Renthal |
| Part Number | R0A9 437U-520-40GBSI |
Videos
Renthal Dirt Bike Chain and Sprocket Overview
R1M weight difference EK 520 Chain + Renthal Sprockets VS OEM
How to Install Renthal Rear Sprocket : What Factory Mechanics Always Do • Renthal Tech Tips
Renthal 54 tooth rear sprocket, 2000 Honda CR250R
Installing Renthal R3-3 O-ring chain w/ clip style and rivet style master links • Renthal Tech Tips
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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