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Columbus
My Store
Cycle Gear ColumbusStore Details
Open Today Until 7pm
3635 West Broad Street
Columbus, Ohio 43228
614-869-3115
Over 160 Stores! Change your store.
What’s going on at Cycle Gear
Services
Experienced staff support available on site
Store Events
Meet the local riding community for Bike Nights & more
Shop the Store
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Uh oh - Our system doesn't think this part will fit your 2019 Harley Davidson Softail Heritage Classic 114 FLHCS (change vehicle selection)

Koso

Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2025

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Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2025 Fullscreen Zoom
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$555.61
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Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2025 Instructions

Koso 150CC Big Bore Kit Honda Grom / Monkey

The Koso 150CC Big Bore Kit increases the motor size of a Grom by 17%, stepping up the compression ratio to 11.38:1 from the standard 10:1. This upgrade delivers a marked improvement in power that stands out even more when coupled with a Koso Camshaft and the use of premium fuel.

Features:

  • Cylinder displacement: 150 cc
  • Cylinder material: Aluminum / Black powder coated
  • Piston size: 54 mm
  • Piston type: Forged
  • Compression ratio: 11.38:1
  • Kit includes: piston ring, piston, pin, gasket kit and cylinder
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Uh oh - Our system doesn't think this part will fit your 2019 Harley Davidson Softail Heritage Classic 114 FLHCS (change vehicle selection)

This Product Fits:

Honda
Grom MSX125 2022, 2023, 2024, 2025
Grom MSX125 ABS 2022, 2023, 2024, 2025
Grom MSX125 SP 2024, 2025
Monkey ABS 2022, 2023, 2024, 2025
Product Style Item # Store SKU Manufacturer Product # Availability
Product Style Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2025 Item # 10400154 Store SKU Manufacturer Product # MB640000 Availability In Stock: Ships within 24 hours
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