Engines and Components› Pistons and Piston Rings

BBR Motorsports

XR/CRF100 120cc Big Bore Kit with Cam

$382.95

SKU: 411-HXR-1001

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Overview

The BBR Motorsports 120cc Big Bore Kit with Cam is an engine upgrade designed for XR/CRF 100 dirt bikes. This kit increases displacement and compression, enhancing motor performance and longevity. It includes a high-performance camshaft, new rocker arms, and a large-finned aluminum cylinder with a steel liner.
Show original supplier description
The BBR Motorsports XR/CRF100 120cc Big Bore Kit with Cam is engineered to boost the performance of popular Honda dirt bikes. This kit increases the engine's displacement to 120cc and features a high-compression design, along with large cooling fins on the aluminum cylinder, to improve both power output and motor longevity. Included in the kit are a 58mm piston with a ring set, piston pin, and clips, new rocker arms and adjusters, and a complete gasket kit featuring cylinder head and base gaskets. The installation process is straightforward, as the kit bolts on directly without the need for case boring. This upgrade aims to provide a noticeable performance enhancement for riders looking to get more out of their XR or CRF100. This big bore kit is confirmed to fit all model years of the Honda XR100 and CRF100, specifically the 1981-Present Honda XR100 and the 2004-Present Honda CRF100. The product is currently backordered, with an estimated shipping date of tomorrow, but will ship as soon as it is back in stock.
Vehicle Symptoms
  • Lack of low-end torque on trails
  • Engine feels flat after top end rebuild
  • Burning oil and needing more power
  • Stock power insufficient for hill climbs
  • Wants more displacement without swapping bike
Relevant Conversations
  • BBR 120cc big bore kit vs TB 120 kit for CRF100?
  • How to install BBR big bore kit with cam on XR100?
  • Does BBR 120cc kit require head work?
  • XR100 bogging after install BBR cam kit?
  • Need more power for my CRF100, big bore or stroker?
  • BBR big bore kit reviews for 2002 CRF100F
  • Can I run pump gas with BBR 120cc kit?
  • BBR cam specs vs Hotcams for CRF100
  • Best big bore kit for XR100 for trail riding
  • Will BBR 120cc kit fit 1998 XR100L?

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.

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Specifications

BrandBBR Motorsports
Part Number411-HXR-1001
CategoryEngines and Components
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