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

kostaktinos_mt, Thanks for the quick education on the in's and out's of surface brushless systems. You gave me some good info to consider. It certainly makes sence that the bearings will have much more dirt and crud to deal with in a truck than in my helis, and planes. Unfortunatly I'm having a hard time accepting this. I basicly need to throw all my ingrained experiance from aircraft out the door and accept what you guys have learned through trial and error.

But as an experiment I think this was worth the time, just from the respect that I now know I dont need 2000+watts to match the performance of my FLM EXT Big block T. Since nothing has been purchased specificly for the E-maxx yet I learned a cheap lesson with the Ammo!!

Weather has been cold and wet all week so I haven't had a chance to drive since Sunday night. But I have been thinking hard. With trying to keep the motor RPM's down around 30k, how do outrunner motors do in surface vehicles?? I know most larger helis(See I cant let it go) use outrunners because they tend to produce the best power at around 30k which lets the heli guys run a larger pinion with more teeth contacting the main gear, it's very rare in helis to see inrunners geared for less than high 30k rpm's.

http://www.innov8tivedesigns.com/ind...cPath=21_25_65 I'm thinking the 1400kv on 8s A123 or the 1900kv on 6s A123.

I could also drop to a 4s A123 pack with the Medusa to get the RPM below 40k, I think the drop in available watts would be too much though, unless the medusa can stand 110+a bursts. I did plan to try it on 4s and still will, 19t/65t combo looks decent for top speeds

I believe Medusa was up and running before Neu, so the V1's were probably more Aveox copies, the V2's could be influanced by the Neu design. Since Neu took over the Aveox model motors it makes sence that all these motors would resemble each other.

I agree with the 70-75mm Medusa, I had almost discounted them because of their lack of size. When I siezed the bearing in the Ammo I ordered the Medusa as a replacement before I even checked the Ammo out to see what happened, figured the rotor let loose.

[KaztheMinotaur]

Would the 35-60-2000V2-5 be a good replacement for a Feigao 8XL? Running 5S in a LST2 with Hydra 120.

This motor is similiar in size and KV to the Feigao 12L but it is double the max amps.

[kostaktinos_mt]

buzzsaw,
sorry for the delayed response, i was kinda busy the past two days.
i agree, cars and aircraft have quite some differences in both theory and real-world.

besides dirt, bearings in cars [not just motor bearings; all bearings] suffer severe mechanical shocks. for example when landing after a jump, hub bearings [those that support the wheels] take a serious hit; and if the quality and size aren`t up to par [weight of the vehicle], they fail. for example, if you do a quick search on the old traxxas stampede you will find that people were killing 5x8 bearings in no time, and then replaced the stock carriers in favor of aftermarket ones that could hold larger bearings. same applies [in a lesser extend] to all car bearings, even motor ones and transmission bearings too. when a truck lands after a jump, the wheels stall momentarily, thus causing a massive mechanical shock/wave beating from the wheels to the motor. if this shock isn`t absorbed [slipper clutch], something will break throughout the chain. if there is nothing to bend [tranny or diff case] or break [axles,cvds,shafts,diffs,gears], then the bearings take the impact; usually leading to grindy bearings that spit a tone of heat once they see high rpm again.
some years ago, we were beefing up our emaxxes to handle bl power, and i remember that everytime something was 'steel-ed',something else failed. first it was universals, so we used steel cvds, then it was the stock diffs so we used RR ones, then it was tranny gears, so we used steel gears, then it was the tranny case, so we came up with alloy ones, and then the motor shafts started breaking [feigao 's' and aveox was popular back then], so we used 5mm shafts, and then finally, rims were getting cracked. all these problems went away when the slipper clutch was upgraded and carefully tuned.
so i have come to believe that there isn`t a thing such as 'bulletproof drivetrain'. ultimately, the heavier a vehicle is and the higher the power that 'feeds' it, the higher the necessity of a slipper clutch is.
finishing my thoughts about this matter, i recall some hardcore rock-crawling guys running their trucks with bushings instead of bearings. reason is, that bearings break under the massive torque being produced between counter shafts and counter gears in the transmission, whereas bushings survive this effect without serious efficiency losses [since it`s low rpm, bushings vs bearings doesn`t make any considerable difference,nor efficiency is a primary goal of rock-crawling].


outrunners do well in cars and trucks, and some people are running their vehicles with the 'no center tranny, but an outrunner' concept. it works well, but removes the slipper clutch [which is bad imo].
outrunner + tranny also works well, but mostly for rock-crawling it is being used [where torque is half the world].
another aspect that i am sure many will debate and argue, is that most [not all] outrunners don`t easily put their efficiency above the 90% mark... which is already a reality for good inrunners [eg: plettenberg,neu]. that said, i personally still like outrunners at some applications, but i won`t agree in blind with the 'outrunner is always better than inrunner' idea.


i think your current medusa on 4s [lipo] should do fine [with proper gearing; i would personally start with a 16t and stock spur], although a 36-60-2000v2 on 5s would be perfect in terms of efficiency,reliability, and performance potential. 6s and 36-60-1500v2 would be close to 'as good as it can be'.


as for the feigao 8xl vs 36-60-2000v2:
i had a kb45 8xl [1700kv] in my lgt, and i am seeing similar performance [and temps] between the kb45/14cells nimh and the 36-60-2000v2 on 5s lipo. so i think the feigao 8xl is close to the 36-60-2000v2 [performance wise], but still not as efficient.

in a heavy lst2 conversion, i think the medusa still has the upper hand when compared with the feigao, but still it`s quite small to run ideally; and thus a kb45 would be a better fit in that application. hence my comment about a 75mm long medusa...