Motor Experiment

[MAMBA2200]

so this weekend i got my 3674 leopard 1900kv 4 pole back and i wanted to compare it to my tacon 3674 1900kv 2 pole motor so the test boat was a mystic 29 and running 4s so off to the pond i go i ran the tacon first and using my gps i took it out and run it for 2 minutes brought it in and checked out temps and speed ambient temp was 42 water temp was also low 40's
round 1 tacon 2 pole 2 min run: motor temp was 74 esc temp was 76

round 2 leopard 4 pole 2 min run: motor temp was 84 esc temp was 77

here is the kicker with the tacon motor i had a speed of 49mph with the leopard motor only 46mph

now by all rights the leopard should be the faster motor but it was not and this shocked me because i thought the leopard should have been a little better all around and b4 you say the tacon will not last i have ran the crap out of this 36 dollar motor and is still was faster than the 88 dollar motor i have many tacon motors and ive always had great luck with them never got a bad one by no means am i bashing either motor cause they seem to be clones but for the money difference i just wanted to share my info and findings

[Basstronics]

Did you recharge the batts?

[Fluid]

Wow Scott, don't they teach punctuation in Tennessee? Your post is kinda hard to follow, but the first thing that comes to mind is what packs were you using? Were they both charged to the same voltage and at the same starting temperature for each test? Were the water conditions similar for each run? Did you follow the exact same driving course for each run? If you run the GPS with the Tacon does it give identical speeds on back-to-back runs?

These are both budget motors so variances within each line are to be expected. The Tacon may test out to have a 2001 Kv while the Leopard may actually be a 1915 Kv. Just because they have the same outer dimensions and Kvs does not make them comparable - you'd be surprised what my Kv checker has shown on many motors. I find your test data very interesting, more so after the questions above are answered. Thanks for the effort.

Here is a different test: https://www.rc-monster.com/forum/showthread.php?t=29390

BTW late model Tacons are 4-pole. http://www.hobbypartz.com/96m802-4074-2150kv.html



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[Brushless55]

Wow Scott, don't they teach punctuation in Tennessee? Your post is kinda hard to follow, but the first thing that comes to mind is what packs were you using? Were they both charged to the same voltage and at the same starting temperature for each test? Were the water conditions similar for each run? Did you follow the exact same driving course for each run? If you run the GPS with the Tacon does it give identical speeds on back-to-back runs?

These are both budget motors so variances within each line are to be expected. The Tacon may test out to have a 2001 Kv while the Leopard may actually be a 1915 Kv. Just because they have the same outer dimensions and Kvs does not make them comparable - you'd be surprised what my Kv checker has shown on many motors. I find your test data very interesting, more so after the questions above are answered. Thanks for the effort.



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that's a good point

[MAMBA2200]

yes batts were at same start voltage same temp i did 2 runs with each motor and these were the average btween the 2 runs i ran the same distance within a tenth and same water conditions and the packs were sky lipo 5000mah and 40c all four packs were brand new first run on all four packs the first run on tacon was 49 2nd run 49.2 leopard 46.3 2nd 43.5 and yes the 4074 tacons are 4 pole but the 3674 are 2 pole http://www.hobbypartz.com/96m215-3674-1900kv-9t.html

[Fluid]

Yes, apparently I can't read very well this morning. Very interesting results.



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[siberianhusky]

Very interesting, I've never run a leopard and was going to post and ask if anybody had done a comparison between them and Castle which I have run. Just might be trying one in my new Whip.

[Speedtospare]

Don't the 2 pole motors have more RPM ability per volt? Generally 2 people motors will rev higher and 4 pole will generate more torque no?

[kevinpratt823]

You said all 4 lipos were brand new, correct? I would be interested to see the results after they were all cycled a few times to break them in some. They can be a touch inconsistent when brand new, especially if one's been sitting longer.......

[Fluid]

Don't the 2 pole motors have more RPM ability per volt? Generally 2 people motors will rev higher and 4 pole will generate more torque no?

No, the rpm ability is determined by the motor Kv, not the number of poles. I have raced both 2-pole and 4-pole motors spinning over 40,000 rpm. Comparing two motors of the same size and Kv, one 2-pole and one 4-pole, the latter will pull away from the bank much harder and pull a larger prop at the same rpm.

I've never run a leopard and was going to post and ask if anybody had done a comparison between them and Castle which I have run.

Check out the video for an anecdotal comparison.

https://www.rc-monster.com/forum/showthread.php?t=29390

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[MAMBA2200]

You said all 4 lipos were brand new, correct? I would be interested to see the results after they were all cycled a few times to break them in some. They can be a touch inconsistent when brand new, especially if one's been sitting longer.......

im gonna do it again just for that reason to see how the batteries react

[siberianhusky]

Thats what I was commenting on, thanks for posting that! Interesting about all 3 having about the same amp draw on the same gearing, as he says at the end it would be really nice to test them on a dyno.

[785boats]

Mamba.
If your Tacon motor is a Y wind, & you have the timing up to say 15 degrees or so, you will need to turn the timing down to around 1 - 3 degrees for the Leopard motor, as it is a D wind motor & too much timing will cause extra heat & also not allow the motor to reach max revs. What timing settings did you use on each motor?

But some time ago, both myself and another club member did similar tests between 2 pole 3674 8Xl 2075 kv motors ( both FSD & Feigao ) & the Leopard 3674 2200kv 4 pole motor. Even with the adjusted timing settings the 2 pole motors were cooler & faster than the Leopard with the same props in the same boats. We tried them in both monos & hydros. You would think, as we did, that the extra kv & the extra torque of the extra two poles, that the Leopard would be quicker & cooler. But that's not what we saw. Granted, the Leopard should be able to swing a bigger prop too, but we didn't even bother trying that as we thought they would get even hotter.

Fluid.
I'd be interested in knowing where to get a KV checker too.

Cheers.
Paul.

[MAMBA2200]

i used the same timing 3.25

[Brushless55]

so if the extra mags develop a bit more heat with smaller props, what happens when we over prop with a 2 pole and 4 pole?