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I am thinking about going 3s on my clod or changing the motor to a higher kv. What would be easier on the gear box? 3s lipo on 4000kv or 2s lipo on 5400kv? I don't want to change pinions. What do you recommend I do? Thank you for your help! I currently have 4000kv on 2s.

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In rough numbers:

4000kv @ 11.1v = 44,400rpm
5400kv @ 7.4v = 39,960rpm

If your ESC will take it, swapping to a 3S LiPo is probably cheaper than dropping in two new 5400kv motors.  I can tell you from experience (I have a Clod race truck running dual 5600kv motors on 2S ) that either of these options is gonna be pretty bonkers as far as power goes.

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Depends what you're doing with it.  If racing go with higher kv since there's no need to worry about heat.  If a basher/fun truck go with a big can lower kv motor and up the voltage.  It will have more torque and run much cooler. 

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Thanks guys! So a 4000kv motor on 3s will run cooler than a 5400kv on 2s? Why is that? bRIBEguy says the rpm's are higher with the 3s battery and 4000kv motors. Is 39,960rpm already pretty high? Are the motors gonna heat up quickly?

Just to let you know... My CLod is far from stock. I have a CPE aluminum chassis, great shocks, among many other things. And my ESC's are 2 of the Hobbywing EZRun  MAX10  and motors are Hobbywing 4000kv motors.

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Sorry, I meant a bigger can motor would run cooler, but the lower kv will run a bit cooler as well with the same voltage.  I'm referring to 3660 (550) sized motors.  I much prefer them in monster trucks for the extra torque.  

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Sure, here you go - https://www.hobbywingdirect.com/products/ezrun-3660sl-g2-motors?variant=26945779528

I run the HW knock-off motors in all of my trucks.  Great punch in these and I race them hard.  Here's a link to the seller on Ebay - https://www.ebay.com/itm/132869188466?hash=item1eef9eeb72:g:gucAAOSwZlFis4Dz

I run their 3660 3800kv & 4700kv in SMTs / 3665 3400kv & 3800kv in LMTs / 3652 5700kv in lighter carbon chassis race trucks.  Fantastic motors for the money.  

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1 hour ago, Clodbusterfan said:

Thanks guys! So a 4000kv motor on 3s will run cooler than a 5400kv on 2s? Why is that? bRIBEguy says the rpm's are higher with the 3s battery and 4000kv motors. Is 39,960rpm already pretty high? Are the motors gonna heat up quickly?

Both those RPM numbers (guesstimates?) are very high, yes.  Actual RPM, torque, heat, etc will be determined by many factors (motor brand/model/quality/size used, battery voltage/size/capacity/"C" Rating, gearing, tire size, weight of truck, etc...).  There is always a "try it and see" factor.  The numbers on the motor are just that... numbers.... they don't always reflect reality (same with batteries and "C-Rating").  The 5600kv Castle Creations motors I have are WAY faster and more powerful then some other 5900kv motors I have.  But the CC price was notably higher.

There are lots of great bargains in the RC world, but in general, a "cheaper" product will not produce the same results as a higher end one.

If apples are compared to apples, the 4000kv setup would run cooler due to a lower amperage draw, for any given level of wattage that the motor is putting out.

In a basic (and technically incorrect) formula, Watts = Amps x Volts.  So if your motor is putting out 300w, it would be drawing 40.5amps at 7.4v, yet only 27amps at 11.1v.  Now, this doesn't take into account torque differences between motors, overall efficiency, etc... but it's a good base level equation to show the differences in power draw.

Taking this back to the start though... with dual HW 4000kv motors paired to HW ESC's, you will have a MONSTER of a truck on 3S @Clodbusterfan.  Also, you should post up some pictures of this beast... we're always hungry to see more Clod builds.

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Thanks to both of you guys for all the info!

87lc2:   Don't I need the EZRUN MAX10 SCT ESC to run those motors?

Are the Hobbywing motors as good as the CC motors?

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I use the unbranded Max10 in everything - https://www.ebay.com/itm/132628378354    These are HW but without the labels, same as the motors I sent.  I am currently running 20 or so of them and they're great.  The motors are stronger than Castle by a lot, I don't bother with Castle anymore with the exception of the 1/8 scale stuff.  Castle is more adjustable using CastleLink, but for 99% of what we do with these things the basic adjustments are just fine.  

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Oh nice, a Time Warp Chassis!  Don't see many of those.  Looks like a nice truck.  

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3 hours ago, Elbowloh said:

I'm surprised that no one has suggested 5400kV motor AND 3s.

Way ahead of you there. Only other essential upgrade is another axle.

9s lipo. 3 batteries. 3s lipo. So still 11.1volts.

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50 minutes ago, Clodbusterfan said:

Cool videos thanks for those.

I'll be honest, there was some crunchy noises on 3s if you jam the throttle, enough to make me buy a spare set but if you gradually accelerate, it'll take it fine, or something had come loose in one of my 3 gearboxes, and I hadn't bothered to check.

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