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2025 Indian Roadmaster PowerPlus Dark Horse
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Uh oh - Our system doesn't think this part will fit your 2025 Indian Roadmaster PowerPlus Dark Horse (change vehicle selection)

Koso

Koso Big Bore Piston Honda Grom / Monkey 2014-2020

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Current price: $143.37
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Koso Big Bore Piston Honda Grom / Monkey

Replacement 61mm forged piston for the Koso 170cc Big Bore Kit.

Features:

  • 61mm forged replacement piston for Koso 170cc Big Bore Kit
  • Compatible with 2 valve head
  • Compression ratio 11.5 to 1

Note: This is an aftermarket part built for racing purposes only. Koso is not responsible for any damages caused to the parts, vehicle or to yourself and others. Engine parts are not under warranty nor is collateral damage or cost of labor in cases of malfunction.

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Please review this product's fitment notes & exceptions prior to purchase: Add to Cart

Uh oh - Our system doesn't think this part will fit your 2025 Indian Roadmaster PowerPlus Dark Horse (change vehicle selection)

Fitment Notes & Exceptions
  • This product is not legal for street use on an emissions-controlled vehicle. It may be used on dedicated competition or pre-pollution-controlled vehicles only.

    • Note: This is an aftermarket part built for racing purposes only. Koso is not responsible for any damages caused to the parts, vehicle or to yourself and others. Engine parts are not under warranty nor is collateral damage or cost of labor in cases of malfunction.

    This Product Fits:

    Honda
    Grom MSX125 2014-2020
    Grom MSX125 ABS 2019, 2020
    Monkey 2019, 2020
    Monkey ABS 2019, 2020
    Product Style Item # Store SKU Manufacturer Product # Availability
    Product Style Koso Big Bore Piston Honda Grom / Monkey 2014-2020 Item # 1246465 Store SKU Manufacturer Product # MD623000 Availability Only 3 Left: Ships within 24 hours
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