Ditch the Check Valve - Protect Your Gearbox the Right Way
Many electric dirt bikes come from the factory with a one-way check valve like the Talaria Sting, Zero XE and XB, Stark Varg, Altis Sigma, and so on. Sounds smart until you realize it only lets air out of your gearbox, not back in. This creates a vacuum when the gearbox cools, which can suck in contaminants or even cause your seals to fail over time.
The GritShift Billet Breather Box solves this overlooked issue with a free-flowing design that allows proper pressure equalization both ways. It was originally designed for the Talaria Sting and still mounts directly to all MX3, MX4, and MX5 models using the factory hose clamp points—no mods needed. But we've also seen riders adapt it successfully for bikes like the Stark Varg, Altis Stigma, and Zero XE/XB. The vent hose size is a match based on customer reports; mounting may vary depending on your bike.
Built from CNC-machined billet aluminum, this breather box uses a baffled internal design and sealed cap with an O-ring to keep dirt and water out while letting your gearbox breathe properly. It also doubles as a mini reservoir to catch fluid if your bike tips or crashes.
Important: One-way check valves do more harm than good. They trap pressure and block airflow during cooldowns, leading to vacuum-related seal damage and fluid loss. This breather box prevents that.
Features
- Free flow air design
- Fluid reservoir for instances when your bike lays on its side.
- Direct Mount design to original hose clamp mounting points.
- Baffled Breather to prevent gearbox contaminants
- Billet aluminum CNC design with o ring seal.
Fitment
Talaria Sting MX3 / MX4 / MX5
Note: We have also had customers use this kit for the below listed bikes, however we have not personally verified this first hand!
Altis Sigma
Stark Varg
Zero XE / XB