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Columbus
My Store
Cycle Gear ColumbusStore Details
Open Tomorrow At 10am
3635 West Broad Street
Columbus, Ohio 43228
614-869-3115
Over 170 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
Find out what’s in stock and ready to go
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This product is vehicle specific. Click here to select your vehicle to ensure fitment.

Koso

Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2026

Customer rating is 3 out of 5 stars. Read 1 Review Write a Review
Current price is $555.61
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Members get up to $42.78 in total value with this purchase.

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The Cycle Gear Difference

Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2026 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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Please review this product's fitment notes & exceptions prior to purchase: Add to Cart

This product is vehicle specific. Click here to select your vehicle to ensure fitment.

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.

This Product Fits:

Honda
Grom MSX125 2022, 2023, 2024, 2025, 2026
Grom MSX125 ABS 2022, 2023, 2024, 2025, 2026
Grom MSX125 SP 2024, 2025, 2026
Monkey ABS 2022, 2023, 2024, 2025, 2026
Product Style Item # Store SKU Manufacturer Product # Availability
Product Style Koso 150CC Big Bore Kit Honda Grom / Monkey 2022-2026 Item # 10400154 Store SKU Manufacturer Product # MB640000 Availability In Stock: Ships within 24 hours
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