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SwampDawg
RCC Addict
35t it is then....
the 55t will be so slow youll fall asleep doin so!
matter of fact... 35t is still slow!!
id aim for in the 20`s
the 55t will be so slow youll fall asleep doin so!
matter of fact... 35t is still slow!!
id aim for in the 20`s
The choice is a matter of voltage and efficiency.
On 2S LiPo the 27T motor works well, at moderate efficiency.
On 3S LiPo you can't beat a 35T.
With 4S the 55T has the same power, but even better efficiency!
So the question is, how high voltage can your ESC handle?
On 2S LiPo the 27T motor works well, at moderate efficiency.
On 3S LiPo you can't beat a 35T.
With 4S the 55T has the same power, but even better efficiency!
So the question is, how high voltage can your ESC handle?
I am looking at buying a kit. But i am not wanting to go for lipos yet. i am still new to this. I am useing 5000mah nimh 7cell packs. (8.4v)
SwampDawg
RCC Addict
im not quite sure how bad the difference between the 35t to a 45t (which i had the 45t) is but... i found mine to be a tad slow for trail runs, however the torque was pretty awesome!
tbird2000
Rock Stacker
i only run 2s 3300 mAh and LOVE the 27t. then again, i run pretty hard, but @Olle P is right, its more preference. A 35 would be fine on ATV trails, if you can handle the boredom.
SwampDawg
RCC Addict
i think before you swap a 2s to 3s onto a motor such as 35t to 45t...
you should make sure that the motor is 3s capable right?
Dont you mean to make sure the ESC is 3s capable? Increasing voltage will put more wear on the motor, but I dont think I've ever heard of a motor having a voltage limit.
SwampDawg
RCC Addict
we had slapped in a 3s from a 2s on our C1 buggies and daayuuum did that motor get scorching hot on a 5-10min run. Used x2 heatsink sections on the motor running a fan. This was on the stock brushless motor, x2 3s sticks and a MMP2 ESC. Had we ran it for 5 more minutes it would have probably caught on fire! lmao!
as for limits...yes, on the ESC make sure it can take 3s+
for the motor...im sure this still matters.
spookyseven
Rock Crawler
I think the common cause of overheating motors is overgearing. More voltage amplifies the problem. If this is wrong feel free to correct me.
Hmmmm I've run 2-4s on my BRXL (which of course handles up to 6s) & HH Torquemaster 55t expert (18/87 gearing) for hours on end and havent gotten too hot to touch. My son runs a 45t on 3s with 20/87 gearing and it gets a little warmer than mine because hes either 0 throttle or 100% throttle lol. I know gearing makes a big difference on how hot a motor can run as well as whether your drivetrain is smooth or has some binding.
Anyways back to the question on hand. If you run 2s I'd say go with 27-35t for some 'fun' speed and decent torque. 3s you can run a 45-55t for similar speeds as the 27-35 on 2s, but like mentioned you'll get better efficiency and somewhat longer run times. I run a 55t in most of my rigs and on a 1300mah 3s I get about 1.5-2 hours of run time, when I ran 2000mah 4s I got easily 3+ hours. Granted 55t can be slow for most people.
Anyways back to the question on hand. If you run 2s I'd say go with 27-35t for some 'fun' speed and decent torque. 3s you can run a 45-55t for similar speeds as the 27-35 on 2s, but like mentioned you'll get better efficiency and somewhat longer run times. I run a 55t in most of my rigs and on a 1300mah 3s I get about 1.5-2 hours of run time, when I ran 2000mah 4s I got easily 3+ hours. Granted 55t can be slow for most people.
dieseldee
Newbie
Ive ran a tekin 55t, 45t, and 35t in rigs with 2s and 3s... I've also ran a 27t HH trail master on 2s and 3s. I would say go with a 35t. Its a good choice to do a little rock crawling with, while keeping the rpm's and wheel speed high enough to climb those trail hills that 45-55t crawler motors just cant scratch and claw up the mud with the wheel speed they produce, no matter what size lipo. Seems like all the guys on this thread hit the nail on the head, I really enjoy learning and shooting the rock talk with everyone. I did notice that on 2s my 27t HH trail master got a little sluggish on real torque demanding rock crawling lines. Not sure if this is good advice, bit in my mind I think that 30t motors and under need 3s lipos
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That's a totally different issue!
First I don't believe that motor was lukewarm after a run on 2S, was it?
If you go from running a motor full speed most of the time at low voltage to run it full speed most of the time at a higher voltage the motor will run much warmer, yes.
In crawling you don't use full speed most of the time, but low speed. Then call on full speed for short periods of time.
Then the heat has no time to build up.
My motor is running just as cool on 2S as on 4S on a typical crawling run (give or take a few degrees).
... but also see below:
Overload (caused by overgearing and/or generally high friction) is the main problem.
At load the current consumption goes up. Current consumption = heat development.
A 27T motor, with proper gearing, on 2S will heat up quite a bit when run continuously at full speed. (That's pretty much the definition of "proper gearing" for a racer. If it runs cool you use too little of the motor power and if it overheats you can't use it efficiently.)
A 50T motor on 3S, properly geared, will make the truck go just as fast, but with less heat due to better efficiency!
That's why the Tekin ROC motors are rated for 4S while the Pro4 are only rated for 3S while essentially being the same motors. ROC are meant for crawlers and in that use won't overheat on 4S. The Pro4 racing motors are both less efficient (using lesser turn armatures) and are run more of the time at more throttle.
