Engines and Components› Engines, Blocks and Components

BBR Motorsports

138cc Big Bore Kit

$186.96

SKU: 411-HCF-1201

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In Stock
Ships by Sep 9
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$100 Minimum Order
30 Days Return
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Overview

The BBR 138cc Big Bore Kit is a performance upgrade designed for the CRF125F. This kit offers the largest bore size without requiring modification to the engine cases for cylinder sleeve clearance. It includes a new aluminum cylinder with a steel sleeve, a lightweight 55mm aluminum piston kit, and necessary gaskets.

This kit features a 10.25:1 compression ratio, providing a noticeable increase in power for your CRF125. It is a direct bolt-on application for Honda CRF125F models from 2013 to the present.
Show original supplier description
The BBR 138cc Big Bore Kit is engineered to deliver enhanced performance for your Honda CRF125F. This comprehensive kit allows for a significant increase in displacement to 138cc without the need to machine the engine cases for additional cylinder sleeve clearance, making it an easy bolt-on power upgrade. Included in this kit is a newly designed aluminum cylinder featuring a durable steel sleeve for longevity. It also comes with a lightweight 55mm aluminum piston kit, specifically chosen to optimize performance and reduce reciprocating mass. A complete gasket kit, including cylinder head and cylinder base gaskets, ensures a proper seal and facilitates installation. With a 10.25:1 compression ratio, this big bore kit is designed to extract more power and torque from your CRF125F engine. It is compatible with Honda CRF125F models manufactured from 2013 to the present.

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

BrandBBR Motorsports
Part Number411-HCF-1201
CategoryEngines and Components

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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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