# BBR - 120cc Big Bore Kit w/ Cam for XR/CRF100

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All prices are in US dollars (USD). Shipping and any tax are worked out at checkout.

## Summary

- **Part number:** 411-HXR-1001
- **Price:** $274.95 USD
- **Stock:** Out of stock. It cannot be added to the cart right now. A person can ask to be emailed when it is back: [Get on the List](https://tboltusa.com/store/contact_us.php?pid=9426&stockcheck=true) ([Contact us](https://tboltusa.com/store/contact_us.md))
- **Product id:** 9426
- **Product last changed:** 2026-11-02

## What it fits

The store lists a part under each bike or engine model it is meant for (the categories below) and may name models in the description. Do not assume it fits a bike or engine that is not named here; ask the store first.

- [Japanese Mini Bike Parts > CRF100 and XR100](https://tboltusa.com/store/japanese-mini-bike-parts-crf100-and-xr100-c-100_62.md)

Where a fitment line says "All", it means all years of the model named on that line, not all bikes.

## Description (the store's own text)

BBR Motorsports celebrates one of the best selling dirt bikes of all time with this high-compression 120cc big bore engine kit for the XR/CRF 100. Increased displacement, higher compression and large cooling fins enhance the performance and longevity of the motor. This is the only XR/CRF100 bore kit that matches the new rocker arms perfectly to the new high-performance BBR cam shaft. This kit is ready to go and bolts on with no case boring required. Dyno tests show more than 2HP gain with this kit. Fits ALL model year XR and CRF100's. Stock XR/CRF100 - 53.0mm bore, 45.0mm stroke

**Key Features:**

- High compression
- High performance camshaft with HD valve springs
- New rocker arms and adjusters
- BBR large fin aluminum cylinder with steel liner
- 58mm piston, ring set, piston pin & clips
- Gasket kit including cylinder head and base gaskets

**Application:**

- XR/CRF 100 - 1981-Present

[Installation Instructions (PDF)](http://bbrmotorsports.com/Products/Instructions/411-HXR-1001.pdf)

## Shipping and returns

- Flat rate shipping is $8 for parts orders under $75 and free for most parts orders over $75, within the continental 48 states. Heavy items (engines, complete bikes, suspension) are excluded.
- Full shipping policy: [Shipping policies](https://tboltusa.com/store/shipping-policies-i-6.md)
- Returns: the store's own policy page says how returns, exchanges and cancellations work. Please read it before buying: [Returns, Exchanges and Cancellations](https://tboltusa.com/store/returns-exchanges-and-cancellations-i-11.md) The page begins: "All products returned to T Bolt USA must be reviewed and approved."

## How to buy

This item is out of stock, so it cannot go in the cart now (see Stock above).

Cart: [Shopping cart](https://tboltusa.com/store/shopping_cart.php)

## Photos

- [Photo 1](https://tboltusa.com/store/img/p/9426/bbr-120cc-big-bore-kit-cam-for-xrcrf100-1.e299f55e.jpg)
- [Photo 2](https://tboltusa.com/store/img/p/9426/bbr-120cc-big-bore-kit-cam-for-xrcrf100-2.95f81b2d.jpg)
- [Photo 3](https://tboltusa.com/store/img/p/9426/bbr-120cc-big-bore-kit-cam-for-xrcrf100-3.5e582d6f.jpg)
- [Photo 4](https://tboltusa.com/store/img/p/9426/bbr-120cc-big-bore-kit-cam-for-xrcrf100-4.22abf46a.jpg)

## Support

Since 2004, every purchase from TBolt USA includes access to technical support from our staff of experts and our online [Pit Bike Technical Info Database](https://tboltusa.com/store/tbolt-usa-pit-bike-minimoto-technical-info-database-tech-15.md)!

We have all necessary support parts on hand.

*Most* orders ship same, or next business day, unless otherwise noted above.