difference on lopart motors

[video200]

can somone please enlighten me what the difference between theLeopard Brushless Motor LB-4074 2T 2000kv and the Leopard Brushless Motor LBP4074/2.5Y-2000KV.

i se that one is 2T and the other is 2.5T. but what difference do that give in the real world ?
they have the same spec.
Max Amps Lipo Cell Max Power KV(RPM/Volt) Resistance No-load Current
120A 3-6s 2600W 2000 0.0062 1.7A

tnx
klaus

[siberianhusky]

On the Leopard site the LB motors are 2 pole the lbp are 4 pole.
On the site they don't list a 2 pole 4074, all of them I've seen for sale and the one I have are 4 pole motors.

[video200]

tnx siberianhusky.
so 2 poles and $36 difference between them. might need to get me a few of those 2 poles ones and test them out :D

[siberianhusky]

I'm no electric expert, just started into them after 20+ years of nitro.
I could be dead wrong on this but I was under the impression that a 2 pole motor is less efficient and will run hotter.
Hope somebody else pipes in with a better idea than I have, a smaller Leopard 2 pole may be just the ticket for my small hydro, don't want to spend too much on that one.

[video200]

im far from a exspert my self. have read on this forum a few times that 2 poles can be as good as 4 or more pole motors.
so with a little luck i\we wil be educated :)

[LarrysDrifter]

Two pole motors are much less efficient and do run hotter than a 4 pole.I would stay away from 2 pole motors.Ive had experience with both,and will never run a 2 pole again.

[video200]

i think that lehner and hacker motors are 2 poles as well. so they cant be all bad

[427srule]

A motor with more poles will be more efficient creating less heat. Well worth the extra money now instead of burning up a set of batteries or esc.
I was told Leopard motors may be more efficient than 90%? That would mean getting away with running that bigger prop. When the ice melts, I will know for sure.

[Fluid]

There is nothing wrong with 2-pole motors - the two fastest FE boats in the world ran them. Motor quality has a lot more to do with performance than how many poles a motor has. Comparing a $60 Feigao 2-pole with a $200 Neu 4-pole is apples and oranges in the extreme - Kia versus Acura.

Four-pole motors generally have more torque than two-pole motors of similar size and quality, but efficiency comes more from the quality than pole numbers. Take two top-end motors, a Lehner (2-pole) and a Neu (4-pole) with the same Kv and weight - both will have similar performance and efficiency (90%+). The Neu will spin a larger prop slower, the Hacker a smaller prop faster. When we swapped a Neu 1521 for a Hacker 8XL we saw virtually identical performance in the same hydro. In the end the faster boat will be the one which is set up the best.

Four-pole motors are more popular today because airplane guys like them. Their increased torque is more suitable for planes where prop rpm is greatly limited. 2-pole motors often require a gear box. Now of course the fly guys like the outrunners for the same reason - more torque. But outrunners have limited use in boats due to their size, limited Kv, cooling problems and lower efficiency. Fad has a lot to do with motor availability too.


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[video200]

so for a twin cat (for exsample) you can be just as well off with a $59 2 pole motor as with a $95 4 pole one with the same KV ?
and would the 2 pole motor draw more amps then a 4 pole

[Fluid]

No, that is the opposite of what I said. Does a Kia have the same quality or performance as an Acura? Equal quality motors will give very similar results. You will get better overall performance with the $95 motor assuming quality tracks the cost. But depending on your goals, you may get by with two $59 motors.

Amp draw is largely dependent on the load (prop) and motor efficiency. Twin motors will pull fewer amps per motor for the same speed as a single motor. A great many successful twin cats have been built with 2-pole motors.



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[video200]

tnx fluid.
wil use the 4 pole motors for my teoretical setup (always helps to know the basic chost before breaking the news to the wife) :)