Big Rock 4S ??? ESC whats going on

ErockPzyk

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Running supposed 120amp spektrum esc with 3670 hobby star motor 3050kv how can this take 4s whennseems to get hot on 3s only running 18t should be good right , ?????
 

Edough13

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3050kv is pretty high for 4s. I run a 4s Hobbystar 4068 2400kv with 18t pinion in my Granite and I have to run dual fans to keep it cool even on just 3s. Definitely need to grab a good fan or two for the motor and maybe gear down to like 15t as your still close to stock 3200kv and mine would get cooking on 3s with just 15t pinon running the 3200kv motor.
 

Kla912000

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Running supposed 120amp spektrum esc with 3670 hobby star motor 3050kv how can this take 4s whennseems to get hot on 3s only running 18t should be good right , ?????
As you know, I just went thru your same situation. Was running my Big Rock with a Max10sct and a Hobbystar 3670/3050kv motor with 18t pinion on 4s and was having problems with the motor hesitating on full throttle pulls which turned out to be major cogging. The motor can run 4s but the ESC would thermal after about 5 minutes or so with a 18t pinion. I switched to a Surpass 3670/2650kv with a 19t pinion and now I have no problems whatsoever. Runs great, doesn't overheat and is just plain stupid fast.
 

ErockPzyk

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So what your saying is the 4s esc is not a 4s actually and it sounds like I am going to have to put the 150 back in might as well throw the blx 2400 in it that comes in kraton 4s , same gears and internal should hold . This truck staring to irritate me. The exb obviously has surpassed it in durability, I know it's a basher but unless I am at skate park I expect at least 5 runs before it breaks
 

Kla912000

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So what your saying is the 4s esc is not a 4s actually and it sounds like I am going to have to put the 150 back in might as well throw the blx 2400 in it that comes in kraton 4s , same gears and internal should hold . This truck staring to irritate me. The exb obviously has surpassed it in durability, I know it's a basher but unless I am at skate park I expect at least 5 runs before it breaks
No, not at all what I'm saying. I am saying that the Max10sct is definitely 4s capable. I am running it on 4s right now in my Big Rock. But, I am also saying that the Hobbystar 3670/3050kv motor IS NOT a proper 4s motor. That's where I had the problems at. The ESC clearly states that running on 4s should only use a max kv of 3000kv. I know 3050kv is only a little higher, but it did not run properly in my Big Rock on 4s. On 3s the 3050kv was perfectly fine but no good on 4s. When I switched to a lower kv motor, 2650kv, everything works perfectly on 4s and is stupid fast.
 

Edough13

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Try 4s with the 15t see if you still have the issues. Just the 18t and the higher kv motor is definitely going to stress the ESC. Kinda like I get bad cogging from a start with my 6s Noto stock BLX185 ESC but I run a 15t pinion. It's just too much gearing and high kv for the ESC is all. Like I said above and also @Kla912000 if you drop to a 2400-2600kv motor it will be a different story for sure.
 

Kla912000

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Try 4s with the 15t see if you still have the issues. Just the 18t and the higher kv motor is definitely going to stress the ESC. Kinda like I get bad cogging from a start with my 6s Noto stock BLX185 ESC but I run a 15t pinion. It's just too much gearing and high kv for the ESC is all. Like I said above and also @Kla912000 if you drop to a 2400-2600kv motor it will be a different story for sure.
Yep. Exactly. Max10sct, 3670/2650kv motor, 19t pinion and 4s Yowoo Graphene battery and she is super fast.
 

Edough13

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Ya my Hobbystar 4068 2400kv and blx185 does great in my Granite with 18t pinion. Fast and torquey and even running 4s with the dual fans I run on the motor it stays cooler than the stock setup on 3s did by far.
 

Kla912000

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Ya my Hobbystar 4068 2400kv and blx185 does great in my Granite with 18t pinion. Fast and torquey and even running 4s with the dual fans I run on the motor it stays cooler than the stock setup on 3s did by far.
I only have 1 fan on the motor but it's a pretty
good fan and I'm running my BEC at 7.4v so the fan spins faster and the servo is stronger.
 
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