KTM 200 exc goes electric

Fw compensation= 100
Fw= 4000
I easily hit 8000rpm no load, I havent tested how high it will go.
I dont know how high it would go under load either, this is about how fast I have driven it.

Some numbers:
Time; Volt; bA; Rpm; km/h; Tcont; Tmot; Tcoeff; Power; GPS

10:58:10;90.2;0.1;217;3.8;23;19;31;9;0 0;
10:58:10;87.8;73.4;1045;18.5;23;19;30;6445;0 0;
10:58:10;86.9;73.4;1720;30.5;23;19;32;6378;0 0;
10:58:11;85.7;153.1;2543;45.1;23;19;32;13121;0 0;
10:58:11;84.3;214.4;3261;57.8;23;19;32;18074;0 0;
10:58:12;82.9;280.4;4100;72.7;23;19;18;23245;0 0;
10:58:13;82.8;342.1;4627;82.1;23;19;7;28326;0 0;
10:58:13;82.6;358.7;5205;92.3;23;20;7;29629;0 0;
10:58:14;82.8;358;5575;98.9;23;20;7;29642;0 0;
10:58:14;82.7;351.9;5952;105.6;23;20;7;29102;0 0;
10:58:14;82.1;346.3;6264;111.1;23;20;7;28431;0 0;
10:58:15;82.1;347.9;6579;116.7;23;21;7;28563;0 0;
10:58:17;81.8;365.5;7300;129.5;23;27;6;29898;0 0;
10:58:18;89.4;361.1;6611;117.3;23;28;6;32282;0 0;

The speed numbers are wrong. It is set up for 7:1, and I have 8,181818:1 now.
It seems the top speed was slightly over 110kph when I recalculate.
But I think this tire is a little bigger than the old one, so it is probably not totally accurate anyway.

It seems like it did about 0-110 in about 7 seconds if I read the numbers right.
I also blew the start it seems, I was supposed to be stationary but it seems I was moving in 3kph.
I was actually surprised it pulled as hard as it did on high rpm, deep in to field wekening.

Bartosh said:

j bjork said:

They are not just difficult, they are big too.
305x170
116v max, so up to 28s if charged to 4,14v max.
660pA peak for 10 sec.

Click to expand...

Nope, Sevcon is rated in RMS, I believe it's applicable to boost also.

RPM -> KPH - that's with the old gearing iirc? PM me the logs, I'll give you the time. Tire circumference atm? BTW very nice IR. Did you set 400bA (bypassing the bms)?

Click to expand...

Ah, so they are more powerful than it looks like at first glance then
I can pm the logs if you want to, but I have already sent them to you on telegram :wink:
I have set 400bA, but I have not bypassed the bms. Just set it up to accept higher currents and for a longer time.
I havent measured the wheel circumference now, but when I think of it is probably not far off. The bms speed was about right compared to gps.

This should be about 100kph:
10:58:15;82.1;347.9;6579;116.7;23;21;7;28563;0 0;
So I guess 3-100kph in 5 seconds, that is actually better than I expected.
Because of the low gearing I didnt expect to do very good at higher speed.
Well, maybe it starts to show later, with 2 seconds between 100 and 110.

I made another run with a better phone so I got more log points.
The result where similar, exept from what I remember the 100-110 didnt take 2 seconds.

I wanted to try to do something about the voltage drop. I guess the best way would have been to take measurements on different points to find out what is lost and where. But I dont have access to a multi-meter with some max and min logging or anything at the moment, so I would have to look at it while pulling max amps. And strap it down to to the bike, make connections to relevant measuring points and so on.

If I got it right I seem to have a resistance of about 22milli Ohm in the system before the controller. That is the battery, contactors, fuse, bms and wiring. If I'm not going to get rid of safety features or add even more battery, it leaves the wiring.



I had 16mm2 wiring from the negative contact point outside of the battery, and from the fuse on the positive side.
In that wiring there were also a total of 3 xt150 connections.
I got rid of all that.
With that I lost the ability to bypass the bms if there is a problem, or to quickly connect the nuc 24f.
It hit later that I could have made a pull with the bms bypassed to find out how much voltage drop I have over it.



It is difficult to solder big wires, as they heat up the solder wicks away in the wire making it hard. On this flat surfaces you only get connection on a small part of the wire anyway, so I decided to press on cable ends and bend them in the right direction.



The charge connection was a bit weak, so I did the same thing with a leftover 16mm2 wire.



Perfect fit on the controller, but the 16mm2 phase wires looks tiny..

Looking forward to seeing your results with this mod :thumb:

Me too, it has been raining all day. So no test today.
It seems I forgot to write that it is 25mm2 wiring everywhere on the battery side now.

I hope it makes at least 1v difference. Closer to 2v would be nice, disappointing if it is under 1v..

2V out of 80V is 2.5%
Will you even notice a difference?

The primary goal was not more power, but to be able to pull high amps at low battery without hitting low volt limits.

It has been raining more or less today too, but I couldent help but to do a little test anyway.
I didnt go 0-100, I started at some speed. I dont think I went full throttle right away either.

Time ; volt; amps; rpm; C-temp; M-temp; tcoeff; gps

09:57:33;87.5;0;1879;33.3;26;25;25;0;0 0;
09:57:33;86.9;0;1943;34.5;26;25;29;0;0 0;
09:57:34;86.4;19.8;2059;36.5;26;25;27;1711;0 0;
09:57:34;86.4;80.4;2501;44.4;26;25;28;6947;0 0;
09:57:34;81.4;150.5;3194;56.6;26;25;27;12251;0 0;
09:57:35;80.8;267.9;3707;65.7;26;25;28;21646;0 0;
09:57:35;80.5;267.9;4356;77.3;26;25;7;21566;0 0;
09:57:36;80.6;364;4844;85.9;26;25;7;29338;0 0;
09:57:36;80.6;354.9;5292;93.9;26;26;7;28605;0 0;
09:57:37;80.5;355.1;5664;100.5;26;26;7;28586;0 0;
09:57:37;79.9;345.5;5983;106.1;26;27;7;27605;0 0;
09:57:38;79.9;346.5;6318;112.1;26;27;7;27685;0 0;
09:57:38;80.2;362.5;6624;117.5;26;28;7;29072;0 0;
09:57:39;79.9;345;6820;121.0;26;29;7;27566;0 0;
09:57:39;79.8;358.8;7046;125.0;26;30;6;28632;0 0;
09:57:40;79.7;363.1;7265;128.9;26;31;7;28939;0 0;
09:57:40;79.6;363.2;7382;130.9;26;32;7;28911;0 0;
09:57:40;79.7;361.1;7539;133.7;26;33;7;28780;0 0;
09:57:41;79.5;361.1;7670;136.0;26;33;7;28707;0 0;
09:57:41;79.4;351.1;7756;137.6;26;34;7;27877;0 0;
09:57:42;79.4;358.9;7786;138.1;26;35;7;28497;0 0;
09:57:42;86.7;355.2;7034;124.8;26;36;6;30796;0 0;
09:57:43;86.7;100.1;6767;120.0;25;37;4;8679;0 0;

The result in voltage drop seems disappointing, it seems like the difference is small to non existent.
I held on a little longer, how do you like good power at almost 7800rpm :wink:
And about 120kph. It can probably do more, but I felt like it was enough on dirtbike tires on wet road.

Im also worried that these rpms might kill the controller, so I have actually never tried a top speed run.

It’s weird, i am hoping for about these rpms with 120V
I guess the votols were improved a bit since my early edition. What’s your noload current at 7500rpm?

I did a test with the wheel in the air, so not really no load.
It has a big tire lock, so it has its share of unbalance.

I went from 2000 rpm to 8000, tested and wrote down the values. Then tested next rpm.

2000=3A
3000=4,8A
4000=7,3A
5000=10A
6000=14A
7000=20A
7500=24A
8000=30A

At about 86V, after I was done the motor temp was 45 degrees C (about 20 degrees when I started)
At higher speeds it was jumping around quite a bit because of the unbalance.
The amps was not really stable at higher rpms either, but it is somewhat close I think.

Wait, what? You are running 25mm2 main cables and only get 2V sag at 300A+? Oh man, I wished I did some more research before I went with 50mm2 on mine. Much less PITA to work with 25mm2 :lol:

Very impressive numbers, btw! Seems like I should turn up the amps on the wifeys china ATV with the same motor/controller setup

Do you mean in in the wires themself?

It is more like 7V sag in total in battery, wiring, fuse, contactors and maybe part of the controller. (the numbers come from the controller)
I dont know how much there actually are in the wires. But as it seems to made well below 1v difference to change from 16mm2 and get rid of 3 xt150 connectors, to 25mm2 I think the losses in the wires are minimal. To double the mm2 from that dosent seem to make much sense.

I realized that there are an easy way to determine exactly how much sag there are in the battery, the balance wires to the bms..
Those are not too difficult to reach and still have the bike ride able.

I am a little curious to determine how much losses there are in the different components, but I guess it dosent really matter.

I guess I read a little too fast, I thought you had 2V sag in the system. But 1V in the wires is not bad at all. If I had known I would have kept it to 25mm2 as well. I just went with the same size wires that I found inside the Outlander pack, but I guess that was a bit overkill.

Hi J
My KTM is 99% ready and I wondering if you could help me with my votol 150sp setup . The issue is with ( probably) throttle . I'm using domino 5k . When I connect pc to controller it shows weird throttle values and hall failure ( which disappear after motor start to spin and goes back on when motor stop ) on display page . I can change them but can't store to the controller . Probably it wouldn't be a problem, but when I do motor spin (wheel on the air ) and reach 5.5k on full throttle for 2-3 seconds it lose control until motor stops spinning and than I can spin it again . Read on votol 100&150 thread about the same issues but couldn't find the answer what could help me . I may try hall throttle to see if it will be any changes .

I dont have the same controller, I have SW 2,32 HW 1,13
I can save settings, as long as they are in range where there are limits.

It seems like on these newer ones you do some adjustments on how the motor runs on the second value in sport mode flux-weakening. Maybe something in the second fw settings on the other modes too?
I am not sure exactly, that is just something I remember from reading the votol thread earlier.

As you say your throttle settings are way off.
If you dont have any resistors in line with the + and - to the throttle you probably have to set 0 to low protect and start voltage, and 5,5v to "the end of the" and high. I would sure use resistors to get some safety margin.

I have 0 or 1 in start torque and combinative, dont know if it matters.
In the em 200 thread someone posted a video on how to solve his connection problem, maybe relevant?

Problem solved with 560 Ohm resistor .
It is also mentioned in https://fasterbikes.eu/en/accessories/throttles/203/domino-premium-full-twist-grip-throttle .

Don't suppose you kept the VW BMS boards? Looking for a couple to investigate without risking the ones on my modules.
Awesome build by the way.

Answered in pm

Not much have happened to this bike lately.
I have basically charged it and lubed the chain, and rode it :wink:

I have been more interested in the new build then develop this one further.

But after the last few rides it was obviously needing some tlc.



Hard to see in the picture, but the "dash panel" is pretty bent in a few directions.
The screen dosent really fit anymore, it is pushed down.



There, now it fits again.



Sometimes it is good to have a big alu plate in front of the batteries :wink:



I dont even know what did that high up behind the front wheel :?



This is also a bit hard to see in the picture, but the chain guide is bent in pretty bad.
This was the most urgent fix, well I realized later that there was another pretty urgent fix too :lol:

This:
It was supposed a short video here, but I wasent able to add it.
It just showed a kind of badly bent rear sprocket..

At today's ride it was clear that more work was needed.
I had very noticeable bearing noise from the motor..



I took the pcb off, but left the plastic holder untouched to not mess up the timing.
Notice the washer under the screw in the middle, I think it is meant to be centered..



End covers, both were a bit wet (the bike was just washed)
On the front cover it was clear that it was not the first time, a little corrosion on the alu and more on the bearing



This didnt look to nice:





The seal was not in place properly. Still surprising how much dirt got in

This is how it looks:



The brown on the rotor is just dirt. I guess that it got there trough the bearing ?!



I think I will leave the rotor where it is.. The magnets are really strong, it seems really hard to get it out.
Doing so will probably do more damage than good.

Btw. I wondered how they were able to fit a 138mm rotor in a relatively small shell

They didnt. The rotor is 85mm, the stator is 138mm outside dia.

Thanks for those pics.
They confirm my plan, to handle this motor as if it wasn't watertight at all...

I dont think it is that much of a problem on a street bike.
This one has been driven in mud and been high pressure washed about once a week for a year.

j bjork said:

I dont think it is that much of a problem on a street bike.
This one has been driven in mud and been high pressure washed about once a week for a year.

Click to expand...

Well, my Bultaco won't be used on streets very often.
But not much in mud either... hopefully...
I am living in a dry region, and most driving will probably happen on dusty gravel roads.

It seems like the main reason for all the dirt and water in the connection box is not the seal that was not perfectly in place, but the seal around the phase wires:





I thought it was a little strange that I got that much dirt in there with such a small fault.
There was some other small problems, but to put some sealant around the phase wires is probably a good idea and not very hard to do.

It is back on the bike now, and ready for some riding tomorrow.
Before I hooked up the chain I took some real no load currents:

















In the last one the max value should be 8853rpm

Nice! I’ve thought about doing the same measurements for a long time.

So 1650w in average for 8500rpm, to get a reasonable 85% efficiency accounting just the noload losses one needs to use 11kW at this rpm. At 3kW riding power the efficiency at 8500rpm with just noload losses is down to 65%

Interesting and it's seems clear from the chart why QS has stated 7500 rpm max for this motor, the exponential increase in noload losses take off around those rpms. The curve tricks you a bit since the last measured point is close to 2000rpm extra and the others are roughly 1000rpm apart.