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JT SPROCKETS Sprocket - Rear - Yamaha - 42-Tooth JTR857.42

Part Number: JTR85742
JT SPROCKETS
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SKU:
JTR85742
UPC:
824225309348
MPN:
JTR857.42
Condition:
New
Availability:
Ships Same Business Day
Weight:
1.80 LBS
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$27.85
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Description

A worn or incorrectly sized rear sprocket robs your Yamaha of power delivery and acceleration efficiency—this JT 42-tooth sprocket restores optimal chain-to-wheel ratios for responsive, predictable performance. Computer-designed and manufactured to exacting standards, JT sprockets combine high-carbon steel durability with precision engineering, eliminating the weak link in your drivetrain. Whether you're fine-tuning gearing for track work or replacing worn teeth on your daily ride, this bolt-on replacement delivers the strength and consistency that professionals demand.

  • Tooth Count: 42
  • Fitment: Yamaha-specific
  • Material: C45 high-carbon steel
  • Finish: Heat-treated & bead-blasted
  • Design: Computer-optimized
  • Installation: Bolt-on
  • Part Number: JTR857.42
  • Quality: OEM-equivalent standards
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Specs

MOUNTING POSITION:
REAR
PRODUCT NAME:
SPROCKET
CHAIN SIZE:
520
RIDING STYLE:
ADVENTURE TOURING / DUAL-SPORT
RIDING STYLE:
STREET
MATERIAL:
STEEL
RIDING STYLE:
ATV
TOOTH COUNT:
42
UNITS:
EACH
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Fitment

Fitment for JT SPROCKETS Sprocket - Rear - Yamaha - 42-Tooth JTR857.42

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