Fully Race Ported Athena YZ125/X 144cc Big Bore Kit (2022-2026) - 58mm Cylinder
If you are wanting a ready to rip big bore kit for your Yamaha YZ125 or YZ125X, we have put together the perfect combo. We have combined a brand new Athena 58mm big bore cylinder kit and added our race porting to it for fully new, race ready cylinder kit. Transform your bike into a fire-breathing 144cc powerhouse. this combo can compete handily vs 250f race machines, and is as fun as it gets! This kit offers a substantial upgrade over the standard bolt on athena 144.
Couple it with our custom HPRD Phathead Billet Head and Insert for even better gains, and our custom tuned GET CDI specific to this 144 kit.
Nothing is more fun than a ripping 125cc big bore...and this package delivers smiles!
- Massive Power Gains: Experience a significant jump in horsepower (up to 45 HP with HPRD porting head and CDI!). Substantial improvement over std Athena big bore.
- Complete Kit: Includes 58mm cylinder, modular head with bronze inner dome, forged piston kit, Ergal 7075 power valves, and complete gasket set.
- Superior Design: O-ring head design for enhanced tuning flexibility.
- Enhanced Optimized Porting: Improving upon Athena's expertly designed porting ensures excellent flow characteristics. We have optmized the porting for maximum power.
- Race-Ready: Engineered for maximum combustion efficiency and reliability under demanding race conditions.
Fitment:
- Yamaha YZ125 (2022-2026)
- Yamaha YZ125X (2023-2026)
We stand behind the quality of our performance parts. This kit is backed by HPRD's commitment to excellence and customer satisfaction. Ride with confidence knowing you're equipped with national championship proven shop.
We process orders within 1-2 business days. Expedited shipping options allow you to get your parts faster just in time for race day.
Returns are accepted within 30 days of purchase for unused items in original packaging. A restocking fee may apply for special order items.