D&D PDS High Speed Motor and 8:1 High Speed Gear Experiment...

[TerryH]

Here are the motor testing results from the weekend. Just for the sake of being clear, the controller settings were the same for all the tests and they are as follows:

Max Output: 100%
Throttle up: 3
Throttle down: 3
Brake: 0
Top Speed: 100%
Turbo: On

I did multiple runs for each of these tests and these are the average results of all of those runs. The batteries were charged in-between the stock motor runs and the D&D motor runs so voltages were the same on both sets of tests and I do not believe that differing voltage is a factor in the results. The temperature was around 42 - 45 degrees during all of the tests. I marked off 300' on my street and timed with a digital stop watch for those runs so there is the error factor of me pushing the buttons but that is a good as I could do.

I ran top speed runs first and then did multiple 300' runs to establish an indication of the torque of each motor.

Stock motor results:

Top Speed: 32.2 mph

300' Time: 11.30
300' Speed : 27.04

Ending motor temp: 171 degrees

D&D Motor:

Top Speed: 31.3

300' Time: 11.05
300' Speed: 26.01

Ending motor temp: 111 degrees

Needless to say, I was a little bit disappointed with these results but alas the results are the results and I firmly believe that the numbers accurately represent the performance of each motor in multiple equal tests.

With that being said, the D&D motor obviously has more torque given the lower 300' times and that is a good thing considering the 8:1 gears will require more torque. It is also very encouraging to me that the D&D motor stayed so much cooler. I know that the 8:1 gear will make the motor pull more amps and the D&D motor appears top be capable of taking those amps. The same can not be said of the stock motor as it is nearly to the temp limit with the stock gears.

I got the new rear end painted and I'll re-test and post those results once the 8:1 rear end is in.

Open the floor for your opinions/comments now...

[TerryH]

I did want to add that I did weigh the stock motor and it is 43 lbs which is 11 lbs. less than the D&D.

[Andy4639]

That's some good info Terry. I wish I had 300' of road to test on here!
I'd have to have the kids block off the main road if I did.
The numbers sound good. I like that temp read to. Can't wait to see how it does with the 8:1 on a nice long cruise.
It's always a little worse on the road testing than on a calulator but those are stil some good results.

[yurtle]

Originally Posted by TerryH

I did multiple runs for each of these tests and these are the average results of all of those runs.

Stock motor results:

Top Speed: 32.2 mph

300' Time: 11.30
300' Speed : 27.04

Ending motor temp: 171 degrees

D&D Motor:

Top Speed: 31.3

300' Time: 11.05
300' Speed: 26.01

Ending motor temp: 111 degrees

Needless to say, I was a little bit disappointed with these results but alas the results are the results and I firmly believe that the numbers accurately represent the performance of each motor in multiple equal tests.

Are the motor temps in C?

[TerryH]

Originally Posted by yurtle

Are the motor temps in C?

No, they are F.

[JohnnieB]

Originally Posted by TerryH

........I marked off 300' on my street and timed with a digital stop watch for those runs so there is the error factor of me pushing the buttons but that is a good as I could do..........

Great info - Thanks.

I'm not sure what you used as a marker, but I've found a sound or physical thump is more repeatable trigger than eyeballing visual markers.

FWIW: When I do any timing I nail down a strip of wood furring at beginning and end of speed trap. Anything that can be felt or heard when the front wheels run over it will work.

Your reaction time starting and stopping the stopwatch will be roughly the same and fairly repeatable, so the same delay on both end more or less cancel each other out.

[scottyb]

I am not surprised that the speeds are about the same with the D&D being a little slower. Those are the same results we got on some D&D motors that I put in PDS carts over last summer. I think the gears will get you close to your goal. Those temp results are great!

[TerryH]

Originally Posted by JohnnieB

Great info - Thanks.

I'm not sure what you used as a marker, but I've found a sound or physical thump is more repeatable trigger than eyeballing visual markers.

FWIW: When I do any timing I nail down a strip of wood furring at beginning and end of speed trap. Anything that can be felt or heard when the front wheels run over it will work.

Your reaction time starting and stopping the stopwatch will be roughly the same and fairly repeatable, so the same delay on both end more or less cancel each other out.

Thanks! I'd never have thought of that. I just painted a stripe in the road.

[TerryH]

Originally Posted by scottyb

I am not surprised that the speeds are about the same with the D&D being a little slower. Those are the same results we got on some D&D motors that I put in PDS carts over last summer. I think the gears will get you close to your goal. Those temp results are great!

It was the temp that encouraged me the most. I know that heat is always the issue with the PDS carts and the gears will generate more heat becasuse they will cause the motor to pull more amps.

[scottyb]

Originally Posted by TerryH

It was the temp that encouraged me the most. I know that heat is always the issue with the PDS carts and the gears will generate more heat becasuse they will cause the motor to pull more amps.

I think that the lower heat is a product of the larger windings dissipating the heat better. When does the HS rearend go in?