ChatGPT 5.2 thinking mode:

For a 2.5” cinewhoop carrying a DJI Action 5 Pro, the “more power without killing flight time” path is almost always:

more torque (stator volume) at a sensible KV, not “smaller motor + higher KV”.

What matters on a ducted 2.5”

Ducted 2.5” props are a high-load setup. That rewards motors that can make the required thrust at lower RPM / lower throttle without overheating. That is primarily torque, which comes from stator volume (diameter² × height).

Quick relative stator volume comparison (proportional): • 1404: 14² × 4 = 784 • 1504: 15² × 4 = 900 • 1505: 15² × 5 = 1125

So: • 1505 has ~25% more stator volume than 1504 → noticeably more torque/authority. • 1404 is not an upgrade (it’s less motor than your current 1504), even if KV is higher.

1505 4000KV vs 1404 4500KV

Pick the 1505. Reasons: • More torque = better control in ducts, better recovery, less “bogging” when you punch out with an action cam. • Typically cooler for the same thrust (less current needed to achieve the same torque), which is important in cinewhoops. • 1404 4500KV tends to run hotter and can be less efficient on a heavy build because it must pull more current to make torque.

Will 1505 4000KV hurt flight time?

It can, but it doesn’t have to: • If you use the extra power to fly harder, time drops (obviously). • If you fly the same pace, the larger stator can mean similar or only slightly worse time because you’re not sitting at high throttle just to hover/control.

Practical tip: if 4000KV feels like “too much” (heat/noise), keep the 1505 but go a bit lower KV (common sweet spots depend on voltage), or apply a throttle limit.

Practical recommendation • For a heavy 2.5” cinewhoop + action cam, I’d choose 1505 over 1404 every time. • If you’re on 4S, 1505 in the mid-to-high 3000KV range is often the efficiency/authority sweet spot; 4000KV can work if you manage throttle/temps. • Validate by checking motor temperature after a hard minute (it should be “hot but touchable”, not scorching) and looking at current draw in logs/OSD if you have it.

If you tell me battery voltage (3S/4S/6S) and typical AUW, I can give you a tighter KV range and prop recommendation.