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Best gearing for 2000kv, 6s, 1/8 buggy.

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Best gearing for 2000kv, 6s, 1/8 buggy.

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Old 03-08-2017, 11:39 AM
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Default Best gearing for 2000kv, 6s, 1/8 buggy.

Hi!

Im wondering if Im stuck betwen a rock and a hard stone? My setup is as mentionend in the title: a 2000kv motor and two 3s lipos in serial giving me a max revs at about 44000 rpm. And things get hot way to fast, but more about that later on.


The reson bought this "6s" capable rtr buggy from the french company hobbytech, was to get a buggy that ran cooler then the standard 4s buggy. (there are numerius threds about it on this forum). When I chosed it, I did not have knolegde about the 30k rpm efficency peak/limit :/

The name of the car is hobbytech spirit nxt ep.(I cant post URLs yet)

3210 g without batteries(one of the cars slogans is "lighter".,, yeah right...
SEams like a pretty standard 1:8 buggy with Bevel gears front / rear, steel 13/43t.

46t steel stur.
12t pinion(at the moment)
Motor: leopard 2000kv v2 4275mm. "capable of 6s" 4 polse, sensorless.

The original motor was defekt soI got the leopardmotor by the store instead. I have also a cheap castle fan on the motor, connected to the reciver.

Esc: Rebranded hobbywing 150 A. 5 settings, I think it is pretty mutch the standard rebranded 6s cabable hobbywing. I have no idea what the timing might be Maby some one knows? Same ass the typhons maby?. Dean connectors.
Batteries: turnigy a-spec 3s 65-120c 4500 with bullets(I use a short adapter bullets to deans. The cables have never gotten hot)



The problem: Things get hot. The car cames with a 10t pinion but I have only tried 10t on the first bad motor which I got replaced.( That motor got hot even on 4s with that extreme low gearing)

On 14t, 11,7, on 6s, the esc shut itself down after a few laps on a wide big track. I had a cc blower conected to the esc at that time though.. Hot sumerday. The lipos got really hot too.

On 13t with 6s: better. Still a more topspeed then I need. But I still cant drive for more then half the mah avalible before things got really hot. Motor, betteries. At least the esc did not shut down.

on 12t: Even better. Tried it both on 4s and 6s. It was accepteble temperatures for the lipos and motor. On 6s though, driving on gravel and ice, lipos and motor got hot long before. I even had the epa turned down to like 80%. Punch at lowest setting.(slowest)

Hobbytech SPIRIT NXT EP Buggy ratio chart
Motor Gear (T)

10 11 12 13 14 15 16 pinion.
15,2 13.8 12.70 11,70 10,87 10,14 9,51
38 41 45 49 53 ( mph) without balloning.(on 12,13, and 14 they ballon some.



Considering all the excesive facts I have given(I know I have writen way to mutch text this far), How would you ger it if you wanted to use 6s and keep things cool?(my 4s is for another car, Im not planing on buying more lipos.)

Buying a 11t pinion giving it a top speed at 41 mph reving it to it's limit? A 10t which would really make the motor reaching 44000 rpm more often?

Is there a good way to gear a 2000kv motor on 6s and being able to use all of the mah avalible?....

Other thoughs on my setup are more then welcome.
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Old 03-08-2017, 11:41 AM
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2000kv is too much motor on 6S, you need a lower kv motor!!! You are going to fry your motor. you need like 1400-1600KV
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Old 03-08-2017, 11:53 AM
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I agree, 2000kv is too much for 6s. That setup would be more of a basher delight for top speed runs. But definitely not for the track.
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Old 03-08-2017, 11:54 AM
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I know that now! Why do the companies even sell rtr "6s" capable with 2000kv motors. Arrma does it too. Like I said, Im stuck betwen a rock and a hard stone with this 2000kv motor and my 6s liops.
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Old 03-08-2017, 12:13 PM
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Originally Posted by Thion View Post
I know that now! Why do the companies even sell rtr "6s" capable with 2000kv motors. Arrma does it too. Like I said, Im stuck betwen a rock and a hard stone with this 2000kv motor and my 6s liops.
I assume it's because they use different gearing in the differentials and pinions to allow it. Generally if you want to go 6s for better efficiency you'd want a motor in the 1500kv range.

I've just never heard of an 1/8 buggy running a 2000kv motor on 6s in a racing environment and surviving lol
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Old 03-08-2017, 12:30 PM
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"Batteries: turnigy a-spec 3s 65-120c 4500 with bullets(I use a short adapter bullets to deans. The cables have never gotten hot)"

How long are the heats/races you are doing? I think on a race track, you'd be better off just running one of your 3s batteries until you can get a milder motor, or some 4s packs.
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Old 03-08-2017, 12:54 PM
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After doing some digging, the manual only recommends a 10T pinion with a 2000KV motor.

So I imagine with those higher pinion counts having been run, and not suggested, if the motor or esc quit, its pretty obvious.
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Old 03-08-2017, 01:53 PM
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Yeah I know what the manual says. But come on, some french men wrote it... It is their first 6s buggy. Even the guy at the local hobby store thinks 10t is waaay to low, and recomended 13t or 14t.

If you want to compare it to other buggys runing a 44000 rpm setup, I think it is interesting to look at the "Total Reduction Ratio"(FDR?) , which I wrote some at the scheme. for the useble pinions. for 10t, it is 15,2. The owner of the lhs belives that 10t gives the motor to little load which also might couse excesive heat.. And the ball berings in the motor...
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Old 03-08-2017, 01:55 PM
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Are there some arrma typhons people out there who is running 6s with their 2000 kv motors? For more then a few minutes.
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Old 03-08-2017, 01:57 PM
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As for racing.. I havent been able to drive for more then a few min before cheacking the temps on everything. At this stage, I just want to be able to drive a few laps without overheating it.
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Old 03-08-2017, 02:12 PM
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You could check the drivetrain to make sure there is no binding and it rolls freely without the motor installed. And check the gear mesh between pinion and spur. Too tight and it'll heat up.

But personally I just think it's impossible to run 2000kv on 6s in a racing scenario. I assume the 6s capability is more for speed runs.
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Old 03-08-2017, 02:47 PM
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I do not know where you are racing. I have not seen any 6s buggies racing in France. Are you sure they are running the same motor??

We are all here trying to help, and their manual is in keeping with most motor manufacturer guidelines!

try checking on Rcmag
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Old 03-08-2017, 03:13 PM
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I run a 15T with a 1900kv and 4s so 10t with 2000kv and 6s seems right. So if your buggy runs hot....

Quote:

("Yeah I know what the manual says. But come on, some french men wrote it... It is their first 6s buggy. Even the guy at the local hobby store thinks 10t is waaay to low, and recomended 13t or 14t. ")

... and you don't change your gearing, then its going to run hot. And your local hobby guy is probably doing his best to help out, but if he doesn't own one of those cars and have experience with it, he probably doesn't really know. I cant imagine how fast that thing must be. 1900kv 4s is fast as it is.
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Old 03-08-2017, 03:17 PM
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Also if you have a low C rating battery they will get hot.
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Old 03-19-2017, 01:38 AM
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definitely need to be in the 1200-1600kv range to see 6s benefits id say, also motor/battery dependent.


however if you must use it find the smallest size pinion that will fit (you should get a 9t at least) and turn down your throttle epa accordingly.
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