Engines and Components› Pistons and Piston Rings

Koso

150cc Big Bore Kit

$219.61

SKU: MM640000

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
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Overview

It is made from quality material for longer durability and can be used with a stock engine, providing better results with the Koso 150cc big bore kit.
Show original supplier description
The Koso performance camshaft (MM640000) is an aftermarket engine upgrade designed to enhance performance for Honda Grom and Monkey models from 2022 onwards. This camshaft is constructed from quality materials to ensure durability and is built for racing purposes. It can be utilized with a stock engine for noticeable gains, but will yield even better results when paired with performance upgrades like the Koso 150cc big bore kit. The specifications include an intake and exhaust duration of 230 at 1mm, valve lift of 0.8mm intake and 7.5mm exhaust, a lobe center of 105 for both intake and exhaust, and running clearances of 0.08mm for intake and 0.20mm for exhaust. Please note that this is an aftermarket part built for racing purposes only. Koso is not responsible for any damages to parts, the vehicle, or to individuals or others. Engine parts are not covered under warranty, including collateral damage or labor costs in case of malfunction.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandKoso
Part NumberMM640000
CategoryEngines and Components
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(760) 282-4645 hello@motormia.co

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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