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Koso 170cc Big Bore Kit With 4V Head Honda Grom 2014-2018

Item: P389264

This kit is for Grom owners who are dead serious about getting the most from their engine and who aren't afraid of serious modification. Read More

$854.96
$949.95
Save $94.99 (10%)
Rebate Available! View Details

This product is vehicle specific. Please to ensure fitment.

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Product Details

Koso 170cc Big Bore Kit With 4V Head Honda Grom

This kit from Koso is for riders looking to push their Grom to the absolute limit, far past what Honda's engineers ever imagined. 

To make this possible, Koso has paired their 170cc Big Bore Kit with a 4 valve head conversion.

Installation is no walk in the park; massive changes are required to turn the little Grom into a fire breathing beast. Be sure to check the fitment notes and review the additional requirements document below to make sure you are ready for the challenge. 

Features:

  • Greatly improved engine performance
  • Increases cylinder displacement to 170cc
  • Upgrades engine from 2 to 4 valves
  • Stainless steel 24mm intake valves
  • Stainless steel 20mm exhaust valves
  • Performance cam shaft

Note: Additional parts are required, see the Additional Requirements/Information (pdf) below for additional information.

Product Style RevZilla Item # MFR. Product # Availability
Product Style Koso 170cc Big Bore Kit With 4V Head Honda Grom 2014-2018 RevZilla Item #1246457 MFR. Product #MB623003 AvailabilityAvailable: Requires 1-3 business days of lead time prior to shipment
Please review this product's fitment notes & exceptions prior to purchase: Add to Cart

This product is vehicle specific. Please to ensure fitment.

Fitment Notes & Exceptions
  • This kit should be installed by a skilled or experienced engine mechanic, catastrophic engine failure could occur if this kit is installed or tuned incorrectly
  • Additional upgrades are required when running this kit
  • Fuel tuning is required
This Product Fits
Honda
Grom MSX125 2014, 2015, 2017, 2018

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