The Heavy Hitter Gearbox Breather Kit W/Fluid Reservoir is a CNC-machined billet aluminum breather box, made by Heavy Hitter and sold here at GritShift, that replaces the factory one-way gearbox check valve on the Talaria Sting MX3, MX4 and MX5 and adapts to most bikes with a breather port. Baffled, O-ring sealed, with a fluid reservoir, 0.4 lb.
Specs verified September 2026 against the live GritShift product page and the Heavy Hitter tech sheet.
Specifications
| Material | CNC-machined billet aluminum |
|---|---|
| Internal design | Baffled, free-flow in both directions |
| Cap | Sealed with a nylon O ring |
| Reservoir | Catches oil if the bike tips or crashes |
| Weight | 0.4 lb |
| Mounting | Direct mount to the factory hose clamp points, no modifications required |
| Hardware | Included: 2 x stainless steel socket head screws M4x20, 1 x stainless steel socket head screw M6x20, 1 x nylon O ring |
| Torque, M4x20 screws | 3 Nm (2.2 ft·lb) |
| Torque, M6x20 screw | 10 Nm (7.4 ft·lb) |
| Tools | 3 mm and 5 mm Allen wrench, torque wrench, medium-strength thread locker |
| Tech sheet | Gearbox Breather Kit W/Fluid Reservoir assembly guide (PDF) |
What bikes does the Heavy Hitter gearbox breather kit fit?
- Talaria Sting MX3 (direct fitment)
- Talaria Sting MX4 (direct fitment)
- Talaria Sting MX5 (direct fitment)
- Universal: can be adapted to most bikes with a breather port
Why replace the factory one-way check valve?
Many e-motos leave the factory with a gearbox check valve that only lets air out, not back in. When the gearbox cools after a ride that one-way valve creates a vacuum, and over time that vacuum can suck contaminants past the seals or fail them outright. Heavy Hitter's breather box uses a free-flow design that equalizes pressure in both directions, so no vacuum builds during cooldown. The internal baffle keeps dirt and water out, the O-ring sealed cap locks everything in place, and the built-in reservoir catches oil if the bike tips over or crashes.
What is in the box?
- 1 x top part
- 1 x bottom part
- 1 x nylon O ring
- 2 x stainless steel socket head screws M4x20
- 1 x stainless steel socket head screw M6x20
How do I install the breather kit?
On the Talaria Sting the box mounts directly to the factory hose clamp points with no modifications. You need a 3 mm and a 5 mm Allen wrench, a torque wrench and medium-strength (blue) thread locker. The two M4x20 screws torque to 3 Nm (2.2 ft·lb) and the single M6x20 screw torques to 10 Nm (7.4 ft·lb). The exploded view showing which screw goes where is in the assembly guide (PDF).
Which other bikes have riders fitted it to?
Heavy Hitter lists the kit as universal for most bikes with a breather port, and the product page names bikes that customers have used it on but that GritShift has not personally verified: Altis Sigma, Stark Varg, Zero XE and Zero XB, Talaria Komodo, and the Arctic Leopard XE Pro, EX and EXE. Treat those as customer reports, not verified fitments; the direct fitment is the Talaria Sting MX3, MX4 and MX5. Talaria owners can also read the Talaria Billet Race Suspension Linkage specs and the V2 Talaria Skid Plate specs.
Where can I buy the Heavy Hitter Gearbox Breather Kit W/Fluid Reservoir?
Right here. We sell the Heavy Hitter Gearbox Breather Kit W/Fluid Reservoir at GritShift. Browse every Heavy Hitter part we carry in our Heavy Hitter collection.
