Optimum rpm for trex

[Syphonics]

As above. I am currently using align 2800kv 13t wooden blades at full throttle i am getting 2000rpm, half stick i am getting 1600-17000rpm. Is it too low?

[genexis]

a good headspeed for trex is 2400. < 2000 is far too slow, even for hovering.

[Syphonics]

does that means i have to increase to 15t?

[genexis]

i'll think that it is something else that is loading the headspeed. Maybe your gear mesh or tail belt is too tight. align 2800L series should be using a 13T pinion. Check your build, make sure the gears, main rotor and tail rotor can rotate freely.

[Adrianli]

My Trex 450X is using the align 400S 2800kv motor with 15T pinon.

Getting abt 2200 - 2400 rpm.


U should switch to 15T pinon. 13T pinon is good for beginner learning to hover only.

[Syphonics]

i tired tweaking my trex still rpm low. I adjusted the tail belt and main gear. without the blades, my flybar reads 1800-2000rpm at half stick and 2600-2700rpm at full throttle. With blades its reads 2000-2100rpm at full throttle.

[Adrianli]

i tired tweaking my trex still rpm low. I adjusted the tail belt and main gear. without the blades, my flybar reads 1800-2000rpm at half stick and 2600-2700rpm at full throttle. With blades its reads 2000-2100rpm at full throttle.

Without blades = without any loading.

Therefore sure can overspeed one lah. Simple physics.

[Syphonics]

Calculated rpm for a 13t with 2800kv => (2800x11.1) / (150/13) = 2702 rpm.
But measured rpm without blades only flybar = 2600- 2700rpm. (Full throttle)
With load woodies 315mm = 2000 - 2100rpm.

the question is, which rpm should be referred? with blade or without blade.

[Adrianli]

Ur calculations seems to be the same as what u tached without blades.


For flyers, we tach it while the heli is in flight.


Fit on the 15T to feel the difference!!!

[X34]

Calculated rpm for a 13t with 2800kv => (2800x11.1) / (150/13) = 2702 rpm.
But measured rpm without blades only flybar = 2600- 2700rpm. (Full throttle)
With load woodies 315mm = 2000 - 2100rpm.

the question is, which rpm should be referred? with blade or without blade.

The ideal setting should be minimum or no-change in rpm between loaded(full pitch) and unloaded(0 pitch). If the setup is correct, with load the amp draw should increase. without load < 7 amps.

Ideal rpm between 2000 to 2400. 3000 for extremist.

[koon]

a good headspeed for trex is 2400. < 2000 is far too slow, even for hovering.

Oh.. I think I'm flying under speed, I setup up my head speed between 2000 to 2300 for FF. (AUW 710g),maybe I should tune up higher for 3D in future.

[sookainian]

a good headspeed for trex is 2400. < 2000 is far too slow, even for hovering.

sorry to ask stupid question, but i really dont know. Hmm why Trex need to run at 2400 rmp ? and Raptors only need run at 1800 + ? why le ?

[Tele]

I just bumped mine up ( on gov mode) from 2400 to about 2700.

its sooooo much smoother and stable as well ..but I am running a set of CF blades too now.

it was however a very marked difference!!

[Syphonics]

sorry to ask stupid question, but i really dont know. Hmm why Trex need to run at 2400 rmp ? and Raptors only need run at 1800 + ? why le ?

I think because raptor is bigger in size and more powerful. It is more stable as then micro. As for Trex, previously when using 15t, it is more stable than 13t. BUt of course it draws more power. I notice that micro heli requries more rpm, if not the heli is not stable, it will sway side to side easily and it is not responsive.

[sookainian]

I think because raptor is bigger in size and more powerful. It is more stable as then micro. As for Trex, previously when using 15t, it is more stable than 13t. BUt of course it draws more power. I notice that micro heli requries more rpm, if not the heli is not stable, it will sway side to side easily and it is not responsive.

ic, ok thank you so much