It looks like the cat is officially out of the bag for Bajaj Auto just a few days before the official launch. A recent online spec sheet leak has pulled back the curtain on the upcoming engine update for two of India’s favourite street fighters: the Bajaj Dominar 400 and the Pulsar NS400Z. This isn’t just a simple engine swap; it’s a calculated tactical move. Bajaj is essentially playing the “GST 2.0” tax game to perfection, downsizing the motor to stay under the 350cc threshold while keeping the performance figures surprisingly close to the original 373cc mill.
The New Engine: Smaller Stroke, Same Spirit
The leaked data shows that the new displacement will sit at 349.13cc, which is about a 24cc drop from the previous version. While the bore remains at 89mm, the stroke has been shortened from 60mm to 56.1mm.
The Performance Numbers:
- Power Output: 40.6 PS @ 9,000 rpm.
- Torque: 33.2 Nm @ 7,500 rpm.
Interestingly, these peaks are hit at exactly the same revs as the old motor. You might notice a tiny bit less grunt when pulling away from the lights, but that shorter stroke should make the top-end feel a lot more lively and eager to rev.
Still a “400” in Name
Even though the engine has shrunk, looks like Bajaj isn’t planning on changing the badges. Both bikes will continue to be marketed as 400s, despite the 349cc reality.
When you compare it to the current NS400Z, the drop is minimal—only 2.4 PS and 1.8 Nm less than the current 43 PS and 35 Nm setup. However, here’s the kicker: this “new” 350cc engine actually produces 0.6 PS more than the pre-2025 Pulsar NS400Z and the current Dominar 400. That is a seriously impressive bit of engineering.
The Big Win: A Massive Price Cut?
The real reason for this engine tweak is the “Paisa” factor. By dropping the displacement below 350cc, the bikes fall into a much lower GST bracket, plummeting from 40% down to just 18%.
Because of this tax break, expectations are high that the on-road price for both the Pulsar NS400Z and the Dominar 400 could drop by as much as Rs 25,000. Bajaj seems to have found the ultimate sweet spot: keeping almost all the performance but making the bikes significantly more accessible for the average rider.
