Recumbent Trike Mxus 6T reaching 30mph

[Simonvtr]

Got my package on Thursday from KMS.
6T mxus hub motor
12fet lyen controller
17" moped rim

After installing the kit I was really disappointed at the speed. The torque is great but the speed is lacking.
With the slowest setting 12mph, 2nd 14-15mph, 3rd 17-18mph
48 volt 20amp lipo.
Compared to my 40$ scooter motor this is really lacking some speed. My scooter motor on belt drive was doing 28-30mph while on 24volt.
I am waiting for some wires to hook up my CA3 to see if there is anything that can be done to make it go a bit faster.
I wonder if there are settings in the controller I can change to increase the speed.
But it would void my warranty.

The Phase instructions I got from KMS made the motor run really rough so I followed the flow chart on ES and fixed the phase/hall issue.

Here is a short video of today test run.
[youtube]pmoQuoJGMe4[/youtube]

 

[999zip999]

50v and 20amp setting of controller or is that 20ah of lipo ? A 12 fet can handle 90volts 40amps. Volts make speed. Haven't heard much on 6t.

 

[Simonvtr]

20ah lipo 50v fully charged.
HK Turnigy 20c

I saw KMS video with a 6t on a fat bike running 60v and seemed a lot faster then my setup.
Starting to wonder if there is something on the controller not right.

 

[SlowCo]

The torque is great but the speed is lacking.
With the slowest setting 12mph, 2nd 14-15mph, 3rd 17-18mph
48 volt 20amp lipo.

The Phase instructions I got from KMS made the motor run really rough so I followed the flow chart on ES and fixed the phase/hall issue.

20ah lipo 50v fully charged.
HK Turnigy 20c

I saw KMS video with a 6t on a fat bike running 60v and seemed a lot faster then my setup.
Starting to wonder if there is something on the controller not right.

Could there be a better combination of phase and hall connections than you've found?
And you're comparing a approx. 21" diameter tire with 50V (max. charged) to a 29" diameter tire with 60V (nominal?). That should be a significant difference.

 

[Simonvtr]

Could there be a better combination of phase and hall connections than you've found?
And you're comparing a approx. 21" diameter tire with 50V (max. charged) to a 29" diameter tire with 60V (nominal?). That should be a significant difference.

When I was using the flow chart the first box had to match up all the wires.
So I did and it was rough, then they had you move to the right box and had you change the combo.
It made the motor run really smooth but backward.
The chart then had me swap some hall wires and 2 phase wires and it ran in the correct direction.
I stopped there unless you believe I can get more if I play around with the phase wires again.


When I had my 20" rim with tires which was 23" total and my 24volt scooter motor I was able to hit 30mph.
This moped rim is bigger then my 20" rim with tires.
The rear is 2 inch higher then when I had my 20" bicycle rim. I read somewhere that a 16" moped rim can fit 20" bicycle tires.
That would mean a 17" moped rim is bigger then a traditional 20" bicycle tire?

In the KMS video description said it was 30mph.
I would imagine my trike with it being lower, less weight and better aero would be faster then 18mph.

I will play around with the phase combo again later this weekend.

 

[Simonvtr]

And you're comparing a approx. 21" diameter tire with 50V (max. charged) to a 29" diameter tire with 60V (nominal?). That should be a significant difference.

Am I doing this wrong if I were to think like this?
21" tire diameter tire @ 50v gives me 18mph.
KMS setup 29" @ 60v gets 30mph.
For me to equal KMS speed with the same motor I would have to almost double my tire diameter right?
Or double the volt I am currently running?

Sorry horrible at math.
If I take 18mph/21" tire I get .85mph for each inch?
18mph/50v gives me .36mph each volt?
.36mph x 60v =21mph + (.85mph x 8" tire difference = 6.8mph) = 27.8 mph?

 

[SlowCo]

https://endless-sphere.com/forums/viewtopic.php?f=30&t=63142&hilit=mxus

If you look in the chart in the first post you'll see that you're spot on at 18 mph with a 6T MXUS on 50V (less with a little sag at max throttle) and with a tire diameter of around 21" (17" wheel with 2,25" tire).

And in the rest of the info they show that you need a 5T on 72V with a 21" tire to get to 30.8 mph. So you'll need to up the voltage to the maximum you can go on your controller to get the maximum speed.

 

[Simonvtr]

https://endless-sphere.com/forums/viewtopic.php?f=30&t=63142&hilit=mxus

If you look in the chart in the first post you'll see that you're spot on at 18 mph with a 6T MXUS on 50V (less with a little sag at max throttle) and with a tire diameter of around 21" (17" wheel with 2,25" tire).

And in the rest of the info they show that you need a 5T on 72V with a 21" tire to get to 30.8 mph. So you'll need to up the voltage to the maximum you can go on your controller to get the maximum speed.

I see thank you.
I read that you can change phase amp? does that increase speed?
And how can you adjust the amp draw of the motor? I thought that was static due to winding count.

 

[SlowCo]

I'm afraid the little knowledge I have about all this is from reading on this forum...
I haven't even finished my own build yet.

What I've come across is something like phase/field weakening (?) so the top speed rises. But the reason and theory are way over my head as a newbie. As far as I understand is that a higher voltage results in higher top speed as the motor has a Kv that means a certain amount of rpm per volt. For the 6T MXUS that is 5.96 so 50V would give 298 rpm. As the Kv is "built in" I believe you need more volts for more rpm.

(disclaimer: math was my worst subject in high school...)
30 mph = 0.5 mile / minute = 31680 inch per minute
21" diameter x pi = 66 inch circumference
31680 / 66 = 480 rpm needed for 30 mph
480 / 5.96 = 80,5V

So it seems you're 30,5V short for 30 mph...
Or you need the 3T MXUS to get past 30mph on 50V

 

[Simonvtr]

I ran the motor sim at ebike.ca

@ 50 volt

@ 75 volt

@ 100 volt

 

[Simonvtr]

Would it be safe to run a 10s4p lipo pack along with my current 12s4p pack in series if I need to reach 90-92 volts?
My current pack is made up of 6s 5000mah 20c lipo in 6s4p bricks series together to give me 12s4p = 49.2 volts.
Can I make another pack 5s 5000mah 20c lipo in 5s4p bricks and then series them together 10s4p = 41 volts.
49.2 + 41 = 90.2 volts

 

[Simonvtr]

When I switched over from a belt drive 1000watt 24volt scooter motor to a Mxus 6t hub motor I was really disappointed at the speed.
I traded speed for torque and so far I have hit all the hills I could find around my area and the motor is working great.
Still wanting to go faster then 18mph I asked around ES and thanks to everyone I will be upgrading my current battery pack.
As of right now the pack is made up of HK lipo's 6s4p for a total of 49.2volts 20000mah.
Last week HK had a huge sell on hardcase 4s 5000mah battery for only $14.99.
So I dropped the ball and got 10 of those but will only be using 8 to make 2 packs of 4s4p for a total of 32.8volts 20000mah.
With both packs combine I will have 82volts 20000mah.

What would 82 volts and a 6t feel like when you are on a recumbent trike 10" off the ground?
To find out while waiting for my lipo's to be delivered I wired 2 ryobi 18v battery in series with my current 49.2v pack.
With a multimeter I was reading 86 volts.

Here is a short video I did.
Sorry about the video it was captured on my phone.


[youtube]nhWZWcCcwWs[/youtube]

Looked like the battery sag to 76v and I was pulling around 3300watt.
I was at the bottom of a small hill maybe that why the motor pulled alot of wattage?
Neighbors said something to me as I was about to take off that's why there was a pause.

Simon
.

 

[John in CR]

...I traded speed for torque...

Common misconception. Once you chose a voltage you traded speed and power for being able to use a smaller less capable controller and less powerful battery. All different winds of the motor have exactly the same torque capability and hill climbing efficiency.

 

[Simonvtr]

I have an odd issue or maybe I have something wired wrong. When I setup my mxus DD motor and my 12fet lyen controller I had a 3 speed switch. It worked fine but was told that when I install my CAv3 that the same switch does not work for the CA. So I purchase a switch for the CA from ebike.ca

The new switch hooked into the aux port of the CA. I setup the CA for Legal, Normal, Unlimited. When I went to test each of the setting nothing happens the speed is the same no matter which selection I have it on which is the middle setting of the lyen controller. So I plugged the old 3 switch back into the controller while the new CA switch was plugged into the AUX port of the CA. Now CA switch will only change if I have the Lyen switch on 3. If I disconnect the lyen switch the CA switch will do nothing and just run with the middle settings.

Am I supposed to have the old controller speed switch installed to make the new CA switch work thru the AUX port?
Or do I need to jumper the lyen controller connector for the speed switch and always have it on 3?

Thanks

 

[teslanv]

You can "hard wire" the supplied 3-speed switch by wiring the green and black wires together where the switch plugs into the controller. This will permanently tell the controller to use setting #3 (Fastest setting).

And if you then use the three speed switch for the CA V3, you can set it up to toggle between the three available "Presets" that would need to be configured in the CA. You can configure the Presets with a variety of limits including max speed, max. current and Max. Power.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=55395#p825397

 

[Hexa]

.
.
Here are pictures of the battery packed I worked on
Made a shell out of 1/16 abs sheets.
Used hockey tape to hold everything together.

Each pack is 6s4p

.
.

Where did you get the foam you put on the Lipos?
I need something like this for my pack but don´t know where to buy it.
What is the material that you used for the housing ?

 

[Simonvtr]

Yes I got them at my local Ace Hardware.
I have upgraded since then and placed them inside aluminum diecast box.
Used sheets of neoprene foam I order on ebay to line the box.

 

[Hexa]

Thanks for the quick reply
Just ordered some foam on ebay

 

[999zip999]

Did you get your battery setup at 20s 80volts and what amps and speed did you get ?

 

[Simonvtr]

Did you get your battery setup at 20s 80volts and what amps and speed did you get ?

Hi Zip sorry for the late response.
I am currently running on 22s which is 90v 20ah on a 12fet lyen controller.
The max my CA shows me pulling with the 6t and about 320lbs of weight is 43amps thats going up a hill.
Top speed on a full charge is 31mph so around 30mph.
I have order a usb cable to see if I can change the program a bit but I am unsure what settings to use so doing a bit of reading before I make any adjustment on it.