# Bills Pipes - Aluminum MX2 Big Bore Full Exhaust System for CRF50 and XR50

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- **Breadcrumbs:** [Home](https://tboltusa.com/store/index.md) > [Japanese Mini Bike Parts](https://tboltusa.com/store/japanese-mini-bike-parts-c-100.md) > [CRF50 Z50 & XR50](https://tboltusa.com/store/japanese-mini-bike-parts-crf50-z50-xr50-c-100_122.md) > [Exhaust Pipes](https://tboltusa.com/store/crf50-z50-xr50-exhaust-pipes-c-100_122_131.md) > Bills Pipes - Aluminum MX2 Big Bore Full Exhaust System for CRF50 and XR50
- **Web page:** [this page on tboltusa.com](https://tboltusa.com/store/bills-pipes-aluminum-mx2-big-bore-full-exhaust-system-for-crf50-and-xr50-p-12011.html)
- **Markdown:** [this page as markdown](https://tboltusa.com/store/bills-pipes-aluminum-mx2-big-bore-full-exhaust-system-for-crf50-and-xr50-p-12011.md)
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All prices are in US dollars (USD). Shipping and any tax are worked out at checkout.

## Summary

- **Part number:** 42-CRF50BB
- **Price:** $299.99 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=12011&stockcheck=true) ([Contact us](https://tboltusa.com/store/contact_us.md))
- **Product id:** 12011
- **Product last changed:** 2026-03-17

## 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 > CRF50 Z50 & XR50 > Exhaust Pipes](https://tboltusa.com/store/crf50-z50-xr50-exhaust-pipes-c-100_122_131.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)

Awesome upgrade for your stock or big bore Honda 50! Bills Pipes makes some of the highest quality exhausts on the market. Provides much better flow than stock and some of the aftermarket exhausts available.

**Application:**

- CRF50 - All years
- XR50 - All years

**Specifications:**

- OD at header - 25.2mm
- ID at header - 22.5mm

## 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/12011/bills-pipes-aluminum-mx2-big-bore-full-exhaust-system-for-crf50-and-xr50-1.jpg)
- [Photo 2](https://tboltusa.com/store/img/p/12011/bills-pipes-aluminum-mx2-big-bore-full-exhaust-system-for-crf50-and-xr50-2.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.