Castle 2650 Motor on 6s Lipo
 

..now we all know Castle is saying this motor is for 4s, no warranty on 6s etc etc (fair enough)

But...

Hpi Advertises using it on 6s!

http://www.hpiracing.com/kitinfo/103420/

Is the Flux Tork 2650 significantly different than the Castle motor to allow this???

That motor is the 2200kv, which is 6s capable

Cheers

Actually at the bottom is states "72mph, Flux 2650 kv 6s Lipo" Which is what I am actually referring too.

Sorry should have been clearer.

This has been gone over before when HPI did the same thing with 2650kv in the Vorza Flux buggy. It came down to them saying we don't recommend it, just saying it is possible.

Take it with a grain of salt, it's just the RC manufacturers marketing to customers (read: noobs) who walk into the hobbyshop and say "What's the fastest car/truck you have?"

But if it's advertised, legally it would 'imply' that it's within warranty specs (at least that's consistant with the Trade Practices Act in Australia, not sure on USA)

Looks like a typo in the add I would say

If the car comes with the 2200 motor as standard which is 6s capable, why would you need their option (2650) to run 6s ?

Perhaps the car actually comes with the 2650 and the option is supposed to be the 2200 ?

Cheers

Yes the 2650 can take 6s... My dad has been using 6s and 2650kv for a year or more on his LX-1E. But Longevity MAY not be there... I say MAY because he just shattered the magnet in it YESTERDAY over a full year running with 0 maintenance. BUT it may have overheated from a Binding issue (Drivetrain) and melted/tore the epoxy/kevlar wrap causing the motor to fail at ~58,000 rpm. So there is no definate answer from me. But I say if you dont mind spending the $25 spare rotor fee then have at it! Its a Blast! :lol:

Oh BTW his never even got close to overheating before the binding issue. Even on 6s it topped at 120~

I think it all comes down to weight and wheel/tire setup...

A CC/Neu 2650kV motor will most likely handle 6s for a good while in a 1/8 buggy, because it is very light and has small, light wheels & tires.

Same motor in a 1/8 Truggy, or especially a 1/10 or 1/8 Monster Truck, and I bet it wouldn't last very long at all on 6s, because of the weight of the truck and the size & weight of the wheel & tire combo!

That is just my $0.02, though...

Ok cool, my intention is to put a 2650 in my RC8Be for speed runs on 5s Lipo (don't want to do 6s as it's a bit close to the caps rating when dealing with ripple voltage, I'd rather drop battery life a little and have more headroom for surges etc)

At the moment the car has a MMP and 2200kv motor on 4s Lipo and is great, however I don't think the MMP will handle either the 2200 or 2650kv on 5s Lipo hence the need to change ESC as well.

Obviously a 2650 in a MT on 5/6s is just asking for trouble IMO

I don't see the interest to use the 2650Kv with 6S when you can use the 2200Kv with 6S... With a bigger pignon, the 2200Kv will provide the same speed at a better efficiency and with less amp spikes in the ESC and the battery....
What's the matter ? You can't find a pinion big enough to do the job with the 2200Kv ?

Why do you say this? The 2200 should have a slightly higher efficiency at this range, run cooler, because it's bigger, but the 2200 should have the higher amp draw, when geared for the same speed. .

The 2200 might draw about the same when geared for the same speed. It does spin at a lower rpm than the 2650 would on the same voltage. However the 2200 can pull a taller gearing for an even greater speed at the cost of more amperage.

In my testing between the 1410 and 1415, I found the 1415 would draw more amps for a given speed, plus the average amp draw was always higher. Running a bigger motor, that produces more torque, has to cost something. .

It does cost something for sure. But you also have to take RPM and load into consideration.

..I forgot about motor timing as well. More timing, more amp draw.

I guess my bottom line is this. He said the 2200 would have smaller amp spikes, then the 2650, when they were the same speed. From my experience this is not true, I found the smaller higher KV motor to draw less amps, when geared for the same speed. .

Sometimes I just want a higher rev setup. It sounds more impressive and makes the TX trigger feel like it has a higher resolution.

It's true only if the motors have the same size. Here, between the 2200Kv and the 2650Kv, the difference does not come from the windings but from the length of the rotor (both motor have same windings 1Y and same windings thickness).
Therefore gearing for the same speed, both motors will draw the same amp, but as the 2200Kv will spin lower, there will be less magnetic losses in it, so it will be more efficient and draw a little less amp for the same power.
The longer the motor is, the cooler and more efficient it generally runs, that's true if the motors have the same design and windings.
Given that, a 1520/1Y geared for the same speed will run even cooler than the 1515/1Y.
But its true that for the same size, the lower Kv will need higher voltage. For (simplified) example you can run the 1512/1Y at 120A but not the 1512/1.5Y which is rated at only 80A (more wires turns, less thickness, but lower Kv...).
More Kv means less inductance, meaning more amp spikes (lower response time). "Torque" is sometimes judged at the feeling of the driver, it should be better to talk with torque per amp. Less Kv means more torque per amp.
Hope it's clear :oops:

My example is stemming from a 1410 compared to a 1415. So both 1y

Here's my 1415 on 3s, running 49mph, on 3s in my Pede 4x4

http://pic20.picturetrail.com/VOL133.../395733604.jpg

Here's my 1410 running 49mph on 3s.

http://pic20.picturetrail.com/VOL133.../395660930.jpg

Here's my 1415 on 2s running 30mph

http://pic20.picturetrail.com/VOL133.../395734985.jpg

Here's my 1410 running 33mph on 2s

http://pic20.picturetrail.com/VOL133.../395663191.jpg

The max amps, and the average amps are both higher, with the bigger motor. Even though the speed is the same or lower. Now, it's all pretty close, so I would assume the 2650 and 2200 would be even closer. But I logged probably 10-15 runs with each setup, and the 2400 always drew more amps, and averaged more.

You can't judge efficiency off temps when you are dealing with 2 different sized motors, as the bigger one will always run cooler, given the same load and efficiency. IOW just because the bigger motor is cooler, does not tell you that it is more efficient.

Nice graphs Asheck. Can you do a run with the 1415 motor with same gearing, but lowered timing. Say 0 and 5 degrees and post up the graphs. Please, pretty please, with a malt ball on top.

I'll see what I can come up with :)

This is not the same setup as the above graphs. It's my Slash 4x4 1415 with a SV2 Pro, :lol: I added a cap and bec, radared at 45mph. Also I wasn't near as consistent with the driving on the 5, you can see the 0 had more steady runtime. So if you take out the down time, it had a higher average. I also did not run the same battery in each, but they are matching packs, I'm gonna switch them around, and try to be more consistent.

5* timing

http://i531.photobucket.com/albums/d...ming545mph.jpg

0*
http://i531.photobucket.com/albums/d...43stiming0.jpg

Temps were within a few degees of each other, and the 5* felt better. Pulled a few wheelies with it, couldn't on the 0.

So would you say that 5 degrees of timing is most efficient in your setup?

At the moment, I don't believe I'm educated enough to say. :) I can say, that the 5 timing sure seems to have more power then the 0, and had higher amp spikes , so it would seem that efficiency would be hard to determine, due to different performance.

But I'm doing another run, and it's more confusing. Geared down to 17/54, and pulled 119 amps. WHY!! :)

You might of have some cat hair in between the gear mesh, causing the increased friction. Hence the higher amp draw.

Maybe you had more traction at one point. Was your avg ampdraw about the same or less?

17/ 54 gearing 0 timing , same battery for both runs, performance was very close.
http://i531.photobucket.com/albums/d...7540timing.jpg

5 timing.

http://i531.photobucket.com/albums/d...slash17545.jpg

Take from it what you can :)

You know I am learning, more then max, it is all about the averages.

I have a theory. Lower gearing produces more instant torque, which you can see by the peak reading. Lower gearing also equals to a lower load on the motor, hence the lower avg reading.

Just a Tomballion theory.

I always have longer run times with my 1520/1Y on 4S in my buggy than my 1515/1Y on 4S both setup geared for the same speed. I can't explain why you found the contrary with your results ^^
But it's true that cool does not mean efficient.

Are they geared for the same speed, or running the same speed? I always confirm speed, just in case.

Could be. I've seen lot's of stuff with the datalogger, that I haven't worked out yet. Especially when it comes to bursts.

Ok, so to explain it to a dimwit like me, I have my SC8 with a Castle Neu 2200 geared for 40mph on 4s Lipo. If I go up to 5s Lipo, but adjust my gearing down so that I am still geared for 40mph, will my run times increase and amp draw decrease, or can you go too far as to undergear the motor?

That is conventional thinking, yup, and most graphes & reports I've seen support it- more power in the system and less load on the motor should result in less current draw and longer runtimes.

Also true- there is obviously some le-way regards the perfect gearing but BL motors will tend to run hotter if they are underloaded, since they are able to hit max rpms quickly and stay there. I believe Patrick referred to motors liking partial throttle & escs liking full throttle for maximum efficiency too, so it figures that a motor running full throttle alot of the time will run hotter than the esc will- just gotta try and strike a balance between motor kv, motor size, input voltage & gearing- hence why this hobby is so damn complicated and frustrating at times :lol:

that is the 100A right? maybe you're pulling more than it can read well, so it defaults it all down lower to around the same area?

Your average should go down some.

Yes it is, and I do think that plays into it. But I don't think it defaults, as stuff that should draw higher amps does, but just get's further off, the higher it goes. It might be 5 off at 110 amps, and 30 off at 125. But, I don't know for sure.