7in Motor Testing! T-Motor F90, iFlight XING, RCinPower Smoox, Flyfish Flash 2806.5

[@camdynkellett6782]

I've been waiting for this one! Thanks chris. I built an AOS 7 last year with F90s and within 20h of flight time over a 6 month period, 3 of my 5 motors have developed what I assume is bearing issues and caused serious oscilations at certain throttle levels. Replacing the motors fixed the issue straight away. I'm currently using Eco 2s and I'm stoked with them! I am a little confused why you didn't include the Emax motors since they're substantially cheaper than the rest and would be interesting to see the performance differences. Anyway thanks again for the super informative video!

[@WipeoutFPV]

I went the other way. Eco2 bearings were garbage, switched to F90's and didn't look back!

[@camdynkellett6782]

@@WipeoutFPV Haha interesting experience! For the cheapest by far, I honestly wouldn't be surprised with issues like that but for instance I could buy two full sets of eco 2s for the price of 5-6 F90s. I was stoked with them (F90s) till I had the issues and if Tmotor can help me with the warranty process I'd be more than willing to give them another chance!

[@grampafpv]

Lol that's what I said. Emax ftw. These other motors might be a touch better but at 150% of the cost.....

[@TheRealWhiteDillard]

Never had a great experience with tmotor

[@alainassaf]

nice vid thanks ! I don't see how an extra 20g motor mass matters on a 7" long range rig that weighs 1000g. Also it wont be doing flips and rolls to be penalized by more inertia at the tip of the arms. Intuitively the result we could be looking for is to answer the question "for how long will it fly ?" So maybe comparing the efficiency at say a thrust of 400g+x, where x is the weight of motor, will tell us exactly that.

[@aphinion]

7" Supernova Motor soon? ;) The outcome of these test results and the general wild sizing of the motors feel like there is similar potential hidden as with the 5" versions... what's your take on that?

[@highlandcrawler]

Always a good day when a new Rosser test video drops. I could watch comparisons. I'm super curious where an older style 2212 would fall in with the motors tested? I still fly them on my 7" and get good performance and pretty long flight times.

[@butcher]

Yeah, 7" is mostly used for long range where no big power is needed, from this aspect, the xing 3106 is the winner. I think all BNF 7inch (longrange) drone built with too powerful motors nowdays.

[@VoltageLP]

could you test any of the popular models? EMax ECO II 2807, TMotor 2808, FlashHobby A2807 etc?

[@mongfpv]

Great work, as always Chris. I've just built a 7" with those smoox, it's good to see I've made a wise choice.

[@cstfpv]

next round it would be great to see: BH 2806.5, XNOVA 2806.5, EMAX ECO II, etc.

[@BenToogood]

Yes!! All of the actual good 7 inch motors

[@MCsCreations]

Thanks a bunch for all the testing, Chris! 😊 Stay safe there with your family! 🖖😊 And happy holidays!

[@MrHeretic666]

Why there is no GepRC SpeedX2, which they install on the MOZ7?

[@guyrandom6151]

doesnt Chris work with RCinpower for in own motors ? before the testing started I could already tell RCinpower would top of the field

[@AgroAaronFpv]

Great video, just wish you included some 2808 1900kv comparisons as well.

[@mlentsch]

Thanks, Rosser... but the t-motor 2808 being one of the most popular 7" motors...

[@chrisbee5481]

Yeah, 2808 seems the better 7" prop motor. Iflight, fpvcycle and geprc are even using 2809 motors. Although I like the 2806.5 too. Just not as powerful

[@s.fendless9107]

At 8:55 seconds in the video, you give the motor a throttle step signal (a sudden change from 10 to 50, and then a sudden change from 50 to 10) to test the motor response, but the final result is absolute RPM changes per second In fact, this test measures step response, and the performance indicators of this response do not include changes in the absolute value of the measured value, but should include changes in relative proportions such as rise time, settling time, and overshoot. Taking this motor response test as an example, what we should care about is how long it takes for the motor to change RPM to 90% of the final value when the motor throttle signal steps to a certain value, rather than the absolute RPM value change of the motor, because considering the absolute value change, within a certain KV range, higher KV values must have advantages.

[@gloriousquads]

I wish you ve included emax ECOII and brotherhobby avenger 2806.5 I've built a fr7 with emax for my friend and ul7 with bh for myself. IMO Bh motors are commonly used in 7" + sizes. They needed to be here😊

[@rolliseventeen]

i have 2 sets o f the F90 1300 in use since 2018. i only need bearings, because i have a lot of sand in them. motors still run smooth. had some crashes and hit some trees, but nothing serious.

[@Lostbirdproductions]

Is there a specific reason that you did not test the brother hobby 2806.5 motors? I have been running them since i started fpv and would have really liked to see how they stack up in comparison.

[@dinosabic5383]

Can't wait to see this library of results keep getting built up. Chris, you're basically making an FPV encyclopedia and I'm here for it! Question, that isn't related to this video... Will I be able to fit an HD system inside an AOS-5R? Cheers, mate! Appreciate all your hard work in this field!

[@tito9107]

Me in beginning of this video: It's gonna be RCINPOWER Me at end of video: Called it

[@diverFPV]

Nice video Chris. These test videos are my favorit. I use eMax 2807 eco2 130 KV .After I burned 3 of the motors and damaged the forth , I decided to rewind the motors with one core 0.6mm wire instead of the multi core wire of the original and 12 instead of 10 turns on the stator. With the dril method I found that I had reduce KV below 1200 .But the resistance between phases was 3 - 4 mOhm higher. The motors are working fine but I have no way to check their efficiency scientifically . What do you think ? Are they more efficient than the originall? Take care

[@lemonsquareFPV]

Good choice on 0.6 wire. You are going to have better efficiency from neater windings and the lower KV. Unless you have the equipment to measure wire resistance, ignore the measurement. A multimeter doesn’t cut it. Good job, and happy flying.

[@diverFPV]

@@lemonsquareFPV Thanks . I don't have special equipment. Just a stable current source (1Amp) and I measured the voltage drop between two phases with a multimeter. It was about 0.0565V and with the original wiring it was 0.053V

[@lemonsquareFPV]

@@diverFPV nice Hey, if it’s repeatable, that’s all that matters. But I definitely wouldn’t worry about that difference, as under operating conditions the single 0.6 will stay way more stable and consistent.

[@EB_FPV7333]

hey chris i am really curious how a high kv motor like 2400kv runs on 6s with a motor output limit as it might effect performance. I am part 4s and part 6s with my quad and it automatically tuns a motor output when 6s is in and wondering if it might have different efficiency ,torque and motor responsiveness than a normal 6s motor on 6s

[@dadbyaffiliation6106]

Thank you. super helpful as im specing a aos ul7 LR build :)

[@evanmahendra_]

What motor did you get?

[@alexandreptito8485]

do you knoiw of a motor that would work without any tweaking like motor limitation etc for a 7 in with a 8s li-ion?

[@SebastienChedalBornu]

a little suggestion, maybe add a graphique jsut quicly to note the current consumption for each motor from 0 to 100% thrust. that woudl give a good idea of what to expect

[@TheRealWhiteDillard]

Would like to see Brother Hobby 2810 motors tested for 7/8" 1180kv vs 1350kv something you can freestyle but do cinematic w/ aswell.

[@robinno78]

Since its indoor season for many at this time, wht about testing 1404 tinyturners, xing, … And 1804 motors, xnova, rcinpower..

[@divingfalconfpv4602]

Rebuilding my 8" almost did the 3106 but their chart on theor website looked so inefficient. So i skipped for this other smaller motor. But looking at this maybe i should of did it

[@pablo98798]

how do you normalize by weight? do you take just the motor weight or motor weight + some standard quad weight ?

[@2Meerkats]

I'm also interested in VTOL applications such as biplane-tailsitters, which VTOL but cruise as fixed wing. Could you include FWing/cruise pitch speeds/efficiency and a higher pitched prop, optional data. Is there a wind tunnel in your future 😅?

[@aviphysics]

Why test with a 5" prop of these are to be used with 7" props?

[@ChrisRosser]

These were all tested with a 7" prop. HQ 7x3.5x3 I guess there is a typo on the chart?

[@Kiromos]

Can't wait for a 2800 Supernova :)

[@SOULSHUN7ER]

Interesting test...please try BH 2812 V3 900kv on 8S

[@davidlee50]

From Old School Glo/Nitro/Wood/Foam,, I'd come up with Questions about Prop Pitch/Length and Elevation just because of Air Density. I start out at 4200ft Elevation and it is way different to play in sea level then fly to 4200 ft then to the Clouds for Anarchy flights. I miss Glo topics with these engine tests.

[@nerdfpv]

❤perfekt. Just paired the AOS UL7 EVO with the SmooX 2806 plus❤ perfekt Combo for light Freestyle and some Long/Mid range Cruiser

[@TopCrinkly68]

Thanks another Jen!!

[@icp-trek]

This is valuable content. Thank you Chris.

[@heartofamericafpv5584]

performance really only matters for racing and heat handling is probably the most important metric.

[@frasersteen]

I've always found it weird that despite the massive increase in swept area the thrust of bigger prop setups doesn't really improve so much. Area goes up with the square but desirable thrust of setups seems to increase less than linearly.

[@PenorBethith]

Wheres the Xnova 2806.5?

[@heartofamericafpv5584]

the best 7" motor is the Xnova 2808.

[@rodgerzinke]

hey chris ;love your tests !!!! can you test the MepsKing motors some day?!:D i am using the 2306 Meps motors with 2450kv on 4s and these motors are damn powerfull! but i would like to know how they compare to some others!

[@grampafpv]

That's a 5inch motor bro....

[@rodgerzinke]

@@grampafpv I know my friend

[@DroneDocs]

Ah yes the universally hated company and motors. Man they sure messed up with that sign this contract to only say good things about our cheap products everyone dislikes.

[@rodgerzinke]

@@DroneDocs the motors I use are really good, so I don't understand why everyone hates them

[@cstfpv]

btw Great content as usual Chris!

[@richardheedfpv9626]

Great stuff. Cheers.

[@JoeTaber]

I think you skipped the efficiency section.

[@ken-kamm]

? kzbin.info/www/bejne/gISynYGpa9x2Z8Usi=R_E0rj75Bm97xTVP&t=336

[@gusDoTebyaDoebus]

It seems to me that the weight of the motor should be normalized to the weight of a typical build with this motor.

[@GBoniFPV]

Good video. However, we should not be making generalizations from such a small sample. It is normal for motor kv to be a little off.

[@grampafpv]

Emax eco 2 kills all of these due to price. I would love to see emax eco motors tested, they cost less than all of these.

[@Bigbeardfpv]

Im shocked none of the avenger motors were in here....

[@torpedoLaw]

Forget, the 7 inch quad copter, the best one to fly is the 5 inch. It’s just so much more responsive and more fun than the 7 inch that long range is not even worth it.

[@DroneDocs]

That's just like your opinion man lol Like freestyle is very boring to a lot of people. Hence why freestyle KZbin videos perform so poorly. Long range, mountain surfing, high speed chase. All of these are better with a 7inch.