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Columbus
My Store
Open Today Until 7pm
3635 West Broad Street
Columbus, Ohio 43228
614-869-3115
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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Uh oh - Our system doesn't think this part will fit your 1982 Yamaha Exciter SR185 (change vehicle selection)

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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Uh oh - Our system doesn't think this part will fit your 1982 Yamaha Exciter SR185 (change vehicle selection)

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
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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