Medusa 36-50-3300 Vs. Ammo 36-50-3300

[kostaktinos_mt]

hi there everyone...
i had originally registered to this forum just to post a comment on lutach`s thread, but since i registered, i thought i could chime in and drop my 0.02... :)
since i am new to this forum, i am completely unaware of each individual`s tempos,ideas,likings and such... so in case anyone already knows the stuff being typed below [or disagrees with it], please don`t take it personally...

i think your ammo is partially demagnetized. 'higher than before' rpm [as you put it] and elevated temps [low efficiency along with quite high currents] is a clear,solid indication of this... so essentially, you can say it`s not a 3300kv anymore... a round speculation about the 'revised' kv rating wouldn`t be much difficult to guess/estimate either; if that`s a question troubling you that is... so let`s just say that this isn`t a sharp head-to-head comparison between those two motors...
try contacting tower; they might get you a replacement...

as medusa motors are 4pole motors, it is necessary that the timing is set above 10degrees... the slotted stator design makes it even more necessary... if i were you, i would be running a medium to high timing setting on the MM, and would definately avoid 'low' or 'lowest' settings... 15 degrees is a mediocre setting for a 4pole motor [unless if it is high-kv compared to it`s physical size], and typical settings for the particular genre of motors usually float between 15-20degrees; meaning that even the stock '10 degrees advance' of the MM is quite low for the particular motor...

btw, 3300kv is a bit high for the emaxx imo... that poor ammo would stand a chance if it was a 36-56-2700 or even better the 1800...
*ammo motors on the other hand are rather touchy with the timing... lowest timing on MM should be considered mandatory when running an ammo...

The ammo you're thinking of is a 2600, 36-56-2600. It's much better suited for an emaxx, but still has a tendency to get hot. Anything smaller in an ammo and it would not be enough. I've never ran the 36-50-3300, so I can't comment on it in particular, but I wouldn't have thought to try it either. I have been through 2 of the 56-2600 motors though. I liked them well enough. Not quite feigao, but very similar. I'd place the 36-56-2600 right alongside a 9L. About the same power, heat, and durability.

J.

Interesting input Kostaktinos. Valuable information for running these motors I would think. I'll keep all that in mind for when I get home to run my Medusa.

[kostaktinos_mt]

i missed 100 points worth of rpm/v

Originally Posted by kostaktinos_mt

i missed 100 points worth of rpm/v

That wasn't the point i was trying to make, really. I know you're familiar with the motor. Just wanted to make sure the OP was ;).

J.

[kostaktinos_mt]

i know what you meant man...
i am just teasing up things, to make the atmosphere 'lightweight' [familiar] to me...

LIGHT WEIGHT!!! LIGHT WEIGHT!!! WOOOO! (anyone know who Ronnie Coleman is? Hehehe! )

[kostaktinos_mt]

yeah, i know 'ronnie' [not personally though ], and i also know that my english sometimes sucks big time

Yep that fact that the temps have gone up, speed has gone up, amp draw has gone up. I think it safe to assume I have demagged the rotor to some extent. So this thread will be more of a Medusa reveiw.

As to the timing setting the Medusa liturature says to run between 8-15 degrees advance.

The fact that so many are running ~1800Kv's led me to try the short can 3300's on lower gearing, basicly I traded motor toque for gear torque. These motors are really for a converted HPI NMT, I just wanted to try them out in my Maxx too see how they would perform.

Both motors blow the stock power system out of the water, unfortunatly the Ammo siezed a bearing and overheated, causing the demagnitization of it's rotor and ending the head to head portion of this thread.

Even before the Ammo was damaged it was running much hotter then the Medusa but did give better punch(could be timing related) and possibly slightly higher top speeds, hard to tell just by sight.

The Medusa is much smoother in it's power delivery, more predictable, and just easier to drive.

In the end this setup is only temporary till the MMM becomes available and I buy the motor I reallly want for the Maxx.

Why do you think the 3300Kv is too high for a Maxx? The Ammo is rated for up to 18.5v(61k RPM) The Medusa is rated at 60k RPM. I'm running them in the 45k range, I have an Aveox powered heli that only sees less then 41k spooling it up and when I shut it down after a flight.

The fact that no one would think to try a setup like this is as good a reason as any if you ask me. Ya sure I destroyed a $35 motor but who's to say the bearing wouldn't have siezed in the NMT causing the same damage? The Medusa is performing well at this point, will it continue too is what I want to find out now. No it's not a super high power rig that will run 60mph doing wheelies at 40mph, it will however do mid 30's with 10-12mph wheelies. I can easily jump the road in front of my house(my favorite big air jump). If this power setup continues to perform like this I might not even buy a differant motor but I do still want the MMM to allow for future performance increases.

[kostaktinos_mt]

well, based on my personal point of view and experience, motor bearings have a really hard time at such high rpms... it`s a matter of time for the bearing to bit the dust at either 50 or 60k rpm; unless if it`s top notch [but then again, we are talking about a 35$ motor here- the bearings can`t be top notch]. some years ago, i had to have a motor spinning at 70k, and what i came up with, is two bearings put into each other, so each was spinning roughly at 35k. there wasn`t any other way around it; single bearings failed no matter the brand. what i am trying to say is that you can`t really expect a motor of this cost to withstand 60k rpms... yes the ratings can tell otherwise, but it`s tough to happen in real life. 50k has eventually seized bearings in one of my feigaos [8l], so even 50k is too much imo -especially with cheap motors. the rotor might take it, and the bearings might take it, but for how long is the question...
aveox is a different story allright... and my plett maxx has gone up to 58k rpm, with no side-effects... i wouldn`t do it continiously even if the motor/bearings are top notch though... experimental reasons however, deserve some credit :)

from what i see from the graphs, it seems that you are running with 4s [correct me if i am wrong]. thats about 48-52k rpms... don`t get me wrong, i am not saying that it`s your fault that the bearing on the ammo failed; i am just saying that it`s to be expected [kinda un-avoidable] with a 35$ motor. could have been just a bad/deffective bearing however...
imo,it would probably have survived with a 3s lipo in the nmt, since the nmt is lighter than the emaxx and thus doesn`t require 4s to perform efficiently. at 3s, the rpms would be much more reasonable and safer. the same setup however, would be either underpowered [geared down] or inefficient [geared up] if used in the emaxx.
bearings failing is one reason not to choose high rpms... the other is efficiency, but that`s a long story to be discussed within a couple of lines...

i have a medusa 36-50-2200v2 and a 36-60-2000v2... you can safely gear up with the 50mm one that you have, although 3300kv shouldn`t need much gearing-up. assuming stock emaxx wheels/tires [or similar in weight and dimensions], i think you could run with the 15t without problems.
i currently run mine [36-50-2200v2] with a 22t pinion in my esavage, and i am quite happy [top speed is about 40mph, and everything runs quite cool]...
the same motor made my lgt [about 11,maybe 12lbs] on 5s lipo to pull wheelies all day [with a semi-locked 500k center diff]...

i hadn`t tried the 36-60-2000v2 till today [5s,lgt]... and that`s all i am gonna say!

[lincpimp]

Originally Posted by kostaktinos_mt

well, based on my personal point of view and experience, motor bearings have a really hard time at such high rpms... it`s a matter of time for the bearing to bit the dust at either 50 or 60k rpm; unless if it`s top notch [but then again, we are talking about a 35$ motor here- the bearings can`t be top notch]. some years ago, i had to have a motor spinning at 70k, and what i came up with, is two bearings put into each other, so each was spinning roughly at 35k. there wasn`t any other way around it; single bearings failed no matter the brand. what i am trying to say is that you can`t really expect a motor of this cost to withstand 60k rpms... yes the ratings can tell otherwise, but it`s tough to happen in real life. 50k has eventually seized bearings in one of my feigaos [8l], so even 50k is too much imo -especially with cheap motors. the rotor might take it, and the bearings might take it, but for how long is the question...
aveox is a different story allright... and my plett maxx has gone up to 58k rpm, with no side-effects... i wouldn`t do it continiously even if the motor/bearings are top notch though... experimental reasons however, deserve some credit :)

from what i see from the graphs, it seems that you are running with 4s [correct me if i am wrong]. thats about 48-52k rpms... don`t get me wrong, i am not saying that it`s your fault that the bearing on the ammo failed; i am just saying that it`s to be expected [kinda un-avoidable] with a 35$ motor.
it would probably have survived with a 3s lipo in the nmt, since the nmt is lighter than the emaxx and thus doesn`t require 4s to perform efficiently. at 3s, the rpms would be much more reasonable and safer. the same setup however, would be either underpowered [geared down] or inefficient [geared up] if used in the emaxx.
bearings failing is one reason not to choose high rpms... the other is efficiency, but that`s a long story to be discussed within a couple of lines...

i have a medusa 36-50-2200v2 and a 36-60-2000v2... you can safely gear up with the 50mm one that you have, although 3300kv shouldn`t need much gearing-up. assuming stock emaxx wheels/tires [or similar in weight and dimensions], i think you could run with the 15t without problems.
i currently run mine [36-50-2200v2] with a 22t pinion in my esavage, and i am quite happy [top speed is about 40mph, and everything runs quite cool]...
the same motor made my lgt [about 11,maybe 12lbs] on 5s lipo to pull wheelies all day [with a semi-locked 500k center diff]...

i hadn`t tried the 36-60-2000v2 till today [5s,lgt]... and that`s all i am gonna say!

Very handy info. I just bought a 36-60-1500 to run on 6s in my hyper8 buggy. What is a lgt? some sort of truggy? Maybe a lightning truggy from hotbodies?

[kostaktinos_mt]

yes, its a lightning gt
http://www.hbeurope.com/kit.php?partNo=hb55007&lang=en

essentially a lightning truggy with large wheels,and without a center diff [i added one however to compensate for the luck of slipper clutch and tame down the wheelies since i electrified it ].

[lincpimp]

Ok, one of those! That thing is badass! Can't belive the 60 motor moved that thing around, what was your gearing? And we need pics, forum requirement!

[kostaktinos_mt]

gearing was 12/50 with the medusa, and previously 13/50 with a kb45 8xl...
i use the stock mechanical brakes, and thus running the thing with an airplane 80amp esc with extra input caps and a small/old cpu heatsink
stock rims/tires, 7inch [178mm height roughly]...

i was running 14 nimh cells with the kb45 [too violent for any reasonable bashing with the 5s/flightpower_evo3700].

members at e-savage.com [i am one of the founding members there] hate me because i broke my camera last year and haven`t bought one since
i will be picking one by the end of this month hopefully, otherwise i see myself banned from both forums


those medusa motors seem to carry twice the torque and efficiency you would expect...
i just love 4 and 6 pole motors...

kostaktinos: Have you used the 50mm medusa motor in a 1/10 scale stadium truck or touring car at all? If you have, I'd like to hear what gearing you're able to get away with in a lighter application (1/10 Stadium vs. "1/10" Monster Truck).