Ok. I'm new here. New in this world of RC so don't bite my head off if the questions are a bit simple or have been asked already. [sm=spinnyeyes.gif] (I HAVE been reading.)

BRUSHLESS SYSTEMS. IS ONE MORE EFFICIENT THAN ANOTHER?

I kind of understand the kv rating of motors in that the higher kv motors have higher RPM and less torque. I'm still unsure about the conection between number of turns and kv values. Will a 10 turn motor always be rated at 3500 kv? Also, reading says that a motor with more turns will be more efficient than one with fewer turns. Is this ture, and if yes, WHY? Taxxas' manual for the VXL system (pg8 under kV Rating) says "As the kV increases, the current draw through the electroncis also increases."

My curiousity stems from the coments from members here that with the Traxxas VXL system, batteries 'die fast'. I've read nowhere that 'batteries last forever'. This review of the mamba max 5700 system puts runtime with an IB 3800mAh pack (6 and 8 cells) at around 30 mins. I'd assume that since the VXL is a 10 turn motor, it should have a little longer runtime if used in the same vehicle. What's your opinion/ experience?

Are all magnets and wires created equal? There's a sintered upgrade kit for This novak system I shudder to think that the original rotor consists of bonded Neodymium. Does any motor use special wires to have ultra low resistance?

How significant is the performance of the ESC? I see that the VXL has a resistance of 0.00075ohms while that of the mamba max is 0.0003ohms yet, the VXL supposedly handles 200A continuous while the MM 100A continuous.... What gives? The VXL advertises 'transistors' while the MM advertises MOSFETs. I know MOSFETs can haldle high currents. Are they just using different terms to describe the same thing or is the VXL using older technology and exaggerating the specs?

What's your experience?

Thanks for the patients!!

eebowler.

no all magnets and wire are not created equal

basicly the higher the kv the faster you go and less run time but there is NOtrue mesurement for brushless moters
but you alwase get what you pay for if you buy cheap!

Yeah, I've read that the higher kV results in less runtime but, what if there are two identical vehicles with two identical packs, one with a 7700kV system and the other with a 4600kV system. If both are travelling at the same speed, would one die before the other? What causes the difference?

7700 will be less efficient in that case. Think about it, is your gasoline engine efficient running at 2000 rpms or redline?? I'm assuming that the 7700 is geared lower to take advantage of the extra reving capacity.

VXL uses plain english to explain their ESC. Instead of Mosfets(metal oxide field effect transistor), they just say Transistor for short.

The lower the resistance the better and in this case the mamba wins. Topend motors are more efficient then the low end motors, which cost 4x+ more then chinese made stuff. High end motors produce more power with the same input. Then there is the other factor to consider, which is ...what is the motor built for? Torque, High rpm, massive HP, fast reving, or a balance of little of everything. The mamba is such a motor, with one flaw. It's not user rebuildable.

But yes, the brushless systems with the least resistance(more efficient) are also the ones that are more expensive. Is it worth to spend the money? If you are racing or just want the best, then yes it's worth it.

Mamba is more efficient (lower ESC resistance) and has a 100A continuous current rating so why does Traxxas have a 200A continuous rating? The actual answer doesn't affect anything since I've already ordered a VXL stampede but, the knowledge would be nice.

Thanks.

It's just an inflated rating.

see i just recently went brushles and i think that what made people say the packs last longer is because if your feather your brushless system and dont floor it and only pull as much speed from it as your brushed motor would have it will last longer.my 4600kv mamba will acceperate as fast as my orion 13t mod motor with only 1/3 the throttle.i tried it once and my pack lasted way longer.see brushless will handle so much power that if you floor it you will suckyour pack dry quick.so i guess what you can say is brushless provides longer runtimes OR more power,not both.its like a turbo.if driven at 65 miles an hour and normally through town it will provide better gas mileage but if you floor it and start running major boost and making 500 horse power your tank will be dry quickly.we should do a test to see how much mileage(not runtime) you can get from brushless vs brushed.2 cars,stock equivilent motors,line em up and floor it and see who goes farter.now i know this would be a hard expeerament to do because you would have to be riding in a car chasing it for a mile or more and the brushless would certainly wear the pack quicker than brushed time wise but it would go so much faster.40mph for 5 minutes is 20mph for 10 minutes!i bet the brushless would go farter befoe the pack quit.but yea try to drive it only as fast as a brused motor and it will last much longer,but if you want to squeeze some nos,its there for ya.go brushless.

Yeah. You make sense. At the same speed, brushless will outperform a brushed motor wrt battery life but will suck a battery faster at faster speeds since it has a high current demand.

Cool.