High-performance heavy-duty two-stroke expansion chamber engineered to deliver robust, tractor-like bottom-end and midrange power for modern Austrian big-bore off-road and enduro applications. Constructed from tough 18-gauge carbon steel to withstand severe rock strikes, heavy trail abuse, and extreme thermal cycling while significantly improving low-end torque and throttle response.
Specs & Details
- Manufacturer Part Number: 78-1521
- Alternative Part Number: FMF 025133 / 1820-1342
- Component Type: 2-Stroke Expansion Chamber / Exhaust Pipe
- Material & Construction: Heavy-gauge 18-gauge carbon steel with a nickel-plated finish
Two-Stroke Vehicle Fitment
| Make | Model | Engine Type | Year Range |
| KTM | 250 / 300 SX / XC / XC-W | Two-Stroke Motocross / Off-Road | 2011–2016 |
| Husqvarna | TC / TE 250 / 300 | Two-Stroke Motocross / Off-Road | 2014–2016 |
TSO Garage Note
The essential armor upgrade for putting meaty bottom-end grunt back into mid-2010s Austrian 250 and 300 two-strokes. This heavy 18-gauge chamber builds instant low-end traction so you can lug through sloppy technical climbs without stalling, while easily shrugging off the brutal boulder bashes that would crumple a stock pipe.
