P-Limited Motors - Im going to jump on the hot seat.

[LuckyDuc]

I’m not 100% sure why the Motor lead temp and Max speed fluctuated for the UL-1 on run #2 versus run #1 and #3. My best guess would be that the water was choppier during that heat. The temp sensor may have moved a bit too during the run.

I used my usual “Go to” heat racing prop for each test as I wanted to start with something that I was familiar with from a performance stand point. The only change that I made to the boat was the motor swap and the ESC timing. I used 10 degrees of timing for the UL1, and 0 degrees for the TP.

I didn’t personally try to prop it up to test the temp ceiling.

There is no doubt that increasing your average lap speed by 1 – 2 mph is noteworthy, but the question for those participating in this discussion is… Does this still fit within the “INTENT” of the P-Ltd class (In regards to an acceptable speed range for the class)? Some may feel that an average of 41 mph per lap is too fast, some might find it acceptable.

[Darin Jordan]

There is no doubt that increasing your average lap speed by 1 – 2 mph is noteworthy, but the question for those participating in this discussion is… Does this still fit within the “INTENT” of the P-Ltd class (In regards to an acceptable speed range for the class)? Some may feel that an average of 41 mph per lap is too fast, so might find it acceptable.

First, THANK YOU for the data, Sean... that's exactly what we need here.

Concerning the INTENT... for me, I'm not concerned about gaining or losing 1-2mph, I just want to be able to select a group of motors for "approval" that are similar enough to not have a "single" motor class. We kind of have that now, with the UL-1, and it looks like we'd have that again with the TP, were it on the list.

I know we can't get it perfect, but I think we can get it really close. Just need to figure out where that happy medium is. 3660? 3650?? 36XX ??

That's where I'm trying to figure this out.

[T.S.Davis]

Concerning the INTENT... for me, I'm not concerned about gaining or losing 1-2mph, I just want to be able to select a group of motors for "approval" that are similar enough to not have a "single" motor class. We kind of have that now, with the UL-1, and it looks like we'd have that again with the TP, were it on the list.

It may be that we find all the motors are between 2mph slower and 2 mph faster based on the application. Might be that's perfect. The more data we can gather the better.

[Darin Jordan]

Just some more data to mull over regarding the physical sizes of the current motors.

AQUG7000 (SV27) Advertised at 36x56
AQUG1800/2030 Advertised at 36x56

PRB3310/4017 (Pro Boat) Advertised at 36x50, can measures 36x53.7 overall
DYNM3835/3830 (Dynamite) Advertised at 36x50, can measures 36x56 overall

I inquired with Dynamite and had confirmed that the internals of the motor did not change in dimension with the update to the motor. They lengthened the can to help fit in the larger, 12-awg, motor leads. Rotor and Stator remained at the 36x50 size.

I'll measure again tonight, but I'm almost certain that the internals of the UL-1 and Revolt motors (2030 and 1800) internals measure the same as the Pro Boat/Dyn parts. I'll double check that.

If I'm right about that, it means the we are ALREADY running 36x50 sized motors.

I don't think anyone who has run one would claim that the DYNM3835 1500KV motor is "underpowered" for ANY of our current P-LTD hulls.

[T.S.Davis]

Darin, Tom found a pair of 50mm SSS motors to send but they're both 2080 motors. These did not fair well at all.

So we'll send you:
36x60 1950kv
36x60 1780kv
(2) 36X50 2080kv
4 calling birds
3 french hen
2 turtl..........what were we talking about?

I'll call him on the way home to see if he has anything else that we should throw at your make shift dyno. He's a junky bad as we are. Who knows what's lurking in his archive.

[Darin Jordan]

Darin, Tom found a pair of 50mm SSS motors to send but they're both 2080 motors. These did not fair well at all.

So we'll send you:
36x60 1950kv
36x60 1780kv
(2) 36X50 2080kv
4 calling birds
3 french hen
2 turtl..........what were we talking about?

I'll call him on the way home to see if he has anything else that we should throw at your make shift dyno. He's a junky bad as we are. Who knows what's lurking in his archive.

Sweet. I will text you my address this afternoon once I get out of this cave here at work. :)

[Greg Schweers]

When I tested the TP motor, I checked to see how it pulls off the corners, see how it pulls the top end, and how it comes out of the hole. The TP definitely pulls harder on the top end than the UL1. But the UL1 comes out of the hole better and pulls the turns better. If I had a choice for off shore, I'd use the UL1. I ran the TP in my Mono with a 545; it's probably the second fastest boat in the Club. So, I tried a 645, and it just couldn't pull it like the 545. Today I ran my whip with the Pro-Boat 1500 and an ABC 1915-17; the boat gps'd at 55. I'm sure it could use more prop. With a UL1 motor and the ABC 1715-17, the boat ran 57. Two days ago I tried a Turnigy SK-3 3659 1900 kv. I ran this with an H5, and it ran 56 mph. For the money ($50), this motor could be a good choice. I'll send this motor to Darrin. This year I'm running conservative on all my setups. I want to go a whole year without burning up a motor--10 races so far/0 burnt motors. Even if we have 20 motors on the list, we all know one's going to rise to the top.

[T.S.Davis]

Even if we have 20 motors on the list, we all know one's going to rise to the top.

That's true.

Sadly it may not even be the best motor. Guys are weird. They tend to think "got beat by x,y,z motor...................must...................... .obtain.......................motor x,y,z". A couple fast guys at the pond is all it takes and everyone gravitates to what ever they're running. The success some are having with the 1500's of late may have some to do with the 1500 sure but likely has more to do with the guys spending time with they're boats to find the right combination. The sweet spot.

[revoltrunner]

Sweet. I will text you my address this afternoon once I get out of this cave here at work. :)

Cave ? one of the guys sent me a pic of your office....LOL

[Darin Jordan]

Two days ago I tried a Turnigy SK-3 3659 1900 kv.

They also make this motor in TWO KVs...

Turnigy SK3 Fandrive - 3659-1900kv (90mm EDF)
Turnigy SK3 Fandrive - 3659-1600KV (90mm EDF)

Currently both in stock at Hobbyking for about $51.00.

From a Specs standpoint, it fits right in with the rest of them...

Seems like a consideration at least.

[rayzerdesigns]

[QUOTE=Jeff;640722]And yet Doug and Jeff are the only ones accused of personal attacks and name calling.
Doby, do you think 1-2 miles an hour is a lot faster?
Would you be willing and have time yet this year to try and run the TP motor again and over prop it to see how it responds? I am not asking you to burn anything up so take it easy if you do.

Ray, was the almost 2 mph faster with the same prop you normally run? How much faster was it when you over propped it?


The reason I am asking these questions is I think in theory the TP motor should pull way more prop but it appears to not. I think it is because of the D wind and it is almost max on our esc battery set ups now. This is why I think we need on water data along with Darins evaluations on his bench tester. I suspect that the Y winds with a lower KV could be over propped and gain some speed by getting closer to 100 amp, this is what currently is being done with the 2030. I hope we could keep the speed increase to within the 5% range(or actually less).

I have some opinions on some of the discussion about the specs for the rules, if you would like I would comment on them for this discussion but only if you realize it isn't for attacks but to have rules that are more manageable.

yes jeff that was with the same m 445 prop..when I went up to the 447 it picked up another 2 mph..this was on my limited mono btw..so I went from a max of 44.6 to a max of48.9..4mph is pretty stout..and im sure with a little more tweaking on prop..or different prop,,could get a bit more

[rayzerdesigns]

That's true.

Sadly it may not even be the best motor. Guys are weird. They tend to think "got beat by x,y,z motor...................must...................... .obtain.......................motor x,y,z". A couple fast guys at the pond is all it takes and everyone gravitates to what ever they're running. The success some are having with the 1500's of late may have some to do with the 1500 sure but likely has more to do with the guys spending time with they're boats to find the right combination. The sweet spot.

might not be the easiest to find the right prop for..but potential is there..i haven't found the right prop for lsh yet..but keep trying..as for cat..well that's my baby

[Darin Jordan]

Need to know what you have before you can know where you're going.

I removed the endbell from an example of EACH of the current P-LTD motors. Will measure the stator to get a real idea of the current motor sizes. Have the rotors as well. I'll get some better pics for comparison/discussion later this weekend.

20150903_205228.jpg

20150903_205234.jpg

One thing to note, can length can be very deceiving.

[T.S.Davis]

That's what I thought. You could have a 60mm can with windings that would fit in a 45mm can. I have some motors where the wind is shorter than the can and the rotor is even shorter.

[rayzerdesigns]

I would say that 1 - 2 mph faster averages in a 6 lap heat race is a fair assessment over the original version UL-1 2030 motor. My tests were conducted with the same prop, setup, and water conditions for these 6 lap heats using a Whiplash sport hydro plane.

Does this mean that it should be excluded for consideration... Perhaps. That is for all of you to debate and test over the next season.

I know from my own experience racing with this motor, and against it with the UL1, that the winner of the heat race won because of their driving and setup skills. It takes more the 1 -2 mph to pass someone on the outside.

The TP 3630 1950kv did not run cooler than the UL-1 however. It averaged 16 degree hotter temps on the motor leads than the UL1 with the same setup and water.

The older version UL1 motor (circa 2012) had a bit more top end speed in the straights, ran cooler, and pulled more amps on average. The timing for the UL1 was set to 10 degrees.

The TP 3630 – 1950kv motor pulled less amps than the “old” version UL1 on average, but ran hotter, had less top end speed, but averaged higher speeds overall because it carried more speed through the corners. The timing for the TP 3630 – 1950kv was set at 0 degrees timing.

I can provide the Eagle tree charts for anyone interested in seeing more details.

I didn't think of changing timing..but I run 3 degrees on 2030..so was same on tp..never changed it