My KS18XL Trials, Tribulations, and Failures

[Unventor]

3 hours ago, Marty Backe said:

 

Now you just need to add the personal touch (aka scrape marks) to those pristine pedals. 

Note: I would recommend to clean the pedals arm area before mounting new pedals on a used wheel. Maybe add a little grease on the metal spring piece to avoid rusting to the pedal rod.

Edited April 8, 2019 by Unventor

[meepmeepmayer]

Hey don't dismiss structural rust! With these build qualities and material thicknesses, we need all we can get

[Marty Backe]

Here are the results of my long awaited mountain stress test of the KS18XL. It has better low-end torque than the MSX but runs much hotter than the MSX. It succumbs to Overheat Hill.

 

[meepmeepmayer]

1 hour ago, Marty Backe said:

Finally, I take the KS18XL to my mountain proving grounds, primarily comparing it to the same MSX test. The KS18XL has better low-end power (torque) than the MSX but utterly fails the heat stress test. The MSX remains the best 18-inch wheel for strenuous riding conditions. This is not to say the the KS18XL is a bad wheel. As I state in the video, for climbing or descending super steep hills, I'd rather be on the KS wheel. But for hot days or long up hill slogs, I'll take the MSX any day.

Wow, that is severely disappointing. 75°C instead of 50° (MSX) after that first hill The Inmotion V10 did better overall! What a contrast to @EUC GUY's MSX tests with the car pushing and steep mountain videos!

That sure throws a wrench in my 16X plans. I just want a 16 incher (for the torque) with MSX board and motor or equivalent, is that so hard?

Thank you for a very helpful and interesting video! Looking forward to your Nikola and 16X tests there

By the way, I believe the impact of environment temperature is overstated by a lot of people (including you). Do mosfets getting hot very fast from a high current really care about 10 or 15 degrees +/- in outside temperature, when the overheating happens in a matter of very short time? I don't think so. I can't see the 18XL have done those hills in 10°C, it overheated fast. 1 minute 20 seconds, you'd probably have measured the extra time at a lower temperature in tens of seconds.

[Unventor]

Well it might not matter or could be a world of a difference. 

If I got it right you bought the pre production demo unit right @Marty Backe? 

So a production unit might better or even worse heat despension. I would expect better.

As for the KS16X some tjing will be compatible but since it still is a different design it will also perform different. So since we expect it to be more torque happy it should not need the heat build up to climb a hill, or at least that is what I would expect.

Once we have the first review of a real production unit, then you can start comparing, until then it is just speculations.

Either way we might look for different features, but to me the KS16X seem to fit what I as for a second wheel. But still only guessing. 

I hope KS let us see more when they get into production stage.

[Marty Backe]

34 minutes ago, meepmeepmayer said:

Wow, that is severely disappointing. 75°C instead of 50° (MSX) after that first hill The Inmotion V10 did better overall! What a contrast to @EUC GUY's MSX tests with the car pushing and steep mountain videos!

That sure throws a wrench in my 16X plans. I just want a 16 incher (for the torque) with MSX board and motor or equivalent, is that so hard?

Thank you for a very helpful and interesting video! Looking forward to your Nikola and 16X tests there

By the way, I believe the impact of environment temperature is overstated by a lot of people (including you). Do mosfets getting hot very fast from a high current really care about 10 or 15 degrees +/- in outside temperature, when the overheating happens in a matter of very short time? I don't think so. I can't see the 18XL have done those hills in 10°C, it overheated fast. 1 minute 20 seconds, you'd probably have measured the extra time at a lower temperature in tens of seconds.

I will be testing both of those wheels on the identical trail, so it's going to be interesting.

There's no doubt that the KS18XL runs hotter. Clearly the board temperature rose ~15-degrees vs ~10-degrees on the MSX. And then the steady state running temperature of the 18XL seems to be >10-degrees warmer than the MSX.

I don't know why this would throw cold water on your 16X dreams. They are different wheels after all.

[Marty Backe]

6 minutes ago, Unventor said:

Well it might not matter or could be a world of a difference. 

If I got it right you bought the pre production demo unit right @Marty Backe? 

So a production unit might better or even worse heat despension. I would expect better.

As for the KS16X some tjing will be compatible but since it still is a different design it will also perform different. So since we expect it to be more torque happy it should not need the heat build up to climb a hill, or at least that is what I would expect.

Once we have the first review of a real production unit, then you can start comparing, until then it is just speculations.

Either way we might look for different features, but to me the KS16X seem to fit what I as for a second wheel. But still only guessing. 

I hope KS let us see more when they get into production stage.

I've seen the inside of my KS18XL. I really can't see how it's different from the production units in any way that would affect my test. I doubt the control board is any different.

I think the 18XL is closer to the MSuper than the MSX, and I think the MSuper would overheat here too. The MSX is in a class unto itself (along with the MCM5) 

[Marty Backe]

43 minutes ago, meepmeepmayer said:

Wow, that is severely disappointing. 75°C instead of 50° (MSX) after that first hill The Inmotion V10 did better overall! What a contrast to @EUC GUY's MSX tests with the car pushing and steep mountain videos!

That sure throws a wrench in my 16X plans. I just want a 16 incher (for the torque) with MSX board and motor or equivalent, is that so hard?

Thank you for a very helpful and interesting video! Looking forward to your Nikola and 16X tests there

By the way, I believe the impact of environment temperature is overstated by a lot of people (including you). Do mosfets getting hot very fast from a high current really care about 10 or 15 degrees +/- in outside temperature, when the overheating happens in a matter of very short time? I don't think so. I can't see the 18XL have done those hills in 10°C, it overheated fast. 1 minute 20 seconds, you'd probably have measured the extra time at a lower temperature in tens of seconds.

Seems like the ACM2 is your wheel. But I know, seems too much like your current wheel.

[Smoother]

1 hour ago, Marty Backe said:

18XL seems to be >10-degrees warmer than the MSX.

Maybe the control board is latin.  When I worked the Texas oilfields, the Hispanic guys would always claim Latin women ran 10 degrees hotter.

Edited April 14, 2019 by Smoother

[meepmeepmayer]

1 hour ago, Marty Backe said:

I don't know why this would throw cold water on your 16X dreams. They are different wheels after all.

18XL: has more torque than the Gotway MSX, overheats faster

16X: reportedly has more torque than the Gotway Nikola, ...

(Fill in the dots while expecting to see the same board used in both wheels.)

So far it's only a thought process of "What could still go wrong?" regarding me getting the 16X (I was warming up to the idea every further day), and that's the doubt I now have So you're right, only speculation for now. I was thinking of getting a 16X right away, now I'll wait and see. My ACM must be enough for another full summer+autumn.

1 hour ago, Marty Backe said:

Seems like the ACM2 is your wheel. But I know, seems too much like your current wheel.

Tesla electronics... not worth the upgrade for me. They're too far on the flimsy side for my liking (smaller mosfets). If I spend 2k, it must be bulletproof (or rather crazy-mountain proof) this time (what I initially hoped my ACM would be). If there was a version of the ACM with the MSX electronics, I'd shrug my shoulder at the lack of features and ergonomics and just get one and never look back

[TomOnWheels]

How many of you are climbing this kind of hills on a daily (or even weekly) basis ? It's a test, just to put the wheel to its limits, and see how much it can gives. It's not something user will do every days I guess. I probably never pushed my KS18L to that temperature in all 4000km I did on it...

[Seba]

9 hours ago, meepmeepmayer said:

16X: reportedly has more torque than the Gotway Nikola, ...

 

With the same engine load you'll get more torque with smaller wheel diameter and load is what causes MOSFETs to heat. We still don't know the internals of KS-16X. Even with the same mainboard there may be much better heat dissipation with different wheel case design. Personally I think that KS just reused both engine and control board from 18L/XL in 16X.

In KS-18L/XL there is a really small air volume inside control board casing. This air is recirculated by a small fan in this casing and there is no significant heat exchange with the outside. So I'm not surprised that the wheel failed to pass Marty's "overheat hill test". I think KS-18XL was designed more to be a long range, universal wheel rather than sport & offroad wheel. I've been riding over 5000 km on my KS-18L and 1000 km on my KS-18XL. None of these wheels ever overheated and I've been riding my L on a steep mountain roads during really hot 2018 summer. Of course, I got readings significantly over 60 °C, but this is quite normal.

[meepmeepmayer]

4 hours ago, TomOnWheels said:

How many of you are climbing this kind of hills on a daily (or even weekly) basis ? It's a test, just to put the wheel to its limits, and see how much it can gives. It's not something user will do every days I guess. I probably never pushed my KS18L to that temperature in all 4000km I did on it...

I specifically bought my wheel (ACM) so I could go up mountains and was quite disappointed when it fried on one. Now I understand the limitations of 2016/2017 technology better, and am pacing around in the flat at the foot of the mountains like a caged tiger So any new wheel (a significant investment for me) must be mountain-proof, I don't want to buy nother one that doesn't really do what I want it to do.

The kind of fast overheating like shown in the video is exactly what I worry about (well, at least much better than the wheel frying without warning). The MSX however is absolutely fantastic, strong and cool under such high loads, as @EUC GUY's videos show (it died after over 6+ mins of pushing a car!!! in the same way my ACM died on 5+ minutes on a steep hill, and did a steep mountain for 10 minutes without problems before overheating).

So I have special requirements

4 hours ago, Seba said:

With the same engine load you'll get more torque with smaller wheel diameter and load is what causes MOSFETs to heat. We still don't know the internals of KS-16X. Even with the same mainboard there may be much better heat dissipation with different wheel case design. Personally I think that KS just reused both engine and control board from 18L/XL in 16X.

In KS-18L/XL there is a really small air volume inside control board casing. This air is recirculated by a small fan in this casing and there is no significant heat exchange with the outside. So I'm not surprised that the wheel failed to pass Marty's "overheat hill test". I think KS-18XL was designed more to be a long range, universal wheel rather than sport & offroad wheel. I've been riding over 5000 km on my KS-18L and 1000 km on my KS-18XL. None of these wheels ever overheated and I've been riding my L on a steep mountain roads during really hot 2018 summer. Of course, I got readings significantly over 60 °C, but this is quite normal.

Again, I'm not sure it's only airflow being a problem here. It overheats so fast compared to the MSX (which has no real air flow either) that I'm thinking this is simply due to the design in some way.

And I don't think anyone specifically designs wheels for high loads, it's just what the design ends up to be. MSX got lucky, 18XL apparently not so much in this specific regard.

This isn't to shit on the 18XL or 16X, just some thoughts/worries that this overheat test caused for me. We'll see how the future wheels turn out.

[UniVehje]

Is it time to give the XL to @maltocs and see if he gets the same result as with his V10F on those mountains? 

 

[TomOnWheels]

16 minutes ago, meepmeepmayer said:

I specifically bought my wheel (ACM) so I could go up mountains and was quite disappointed when it fried on one. Now I understand the limitations of 2016/2017 technology better, and am pacing around in the flat at the foot of the mountains like a caged tiger So any new wheel (a significant investment for me) must be mountain-proof, I don't want to buy nother one that doesn't really do what I want it to do.

The kind of fast overheating like shown in the video is exactly what I worry about (well, at least much better than the wheel frying without warning). The MSX however is absolutely fantastic, strong and cool under such high loads, as @EUC GUY's videos show (it died after over 6+ mins of pushing a car!!! in the same way my ACM died on 5+ minutes on a steep hill, and did a steep mountain for 10 minutes without problems before overheating).

So I have special requirements

Again, I'm not sure it's only airflow being a problem here. It overheats so fast compared to the MSX (which has no real air flow either) that I'm thinking this is simply due to the design in some way. And I don't think anyone specifically designs wheels for high loads, it's just what the design ends up to be. MSX got lucky, 18XL apparently not so much in this specific regard.

This isn't to shit on the 18XL or 16X, just some thoughts/worries that this overheat test caused for me. We'll see how the future wheels turn out.

I think it's good to know limits of the wheel (well for safety at least...) and your usage of it shows that there are users with this specific requirement. It's probably a quite low % of users but good is that thanks to users like you we all will have better and stronger wheels. I specifically bought my KS18L to use it only 50% of its power. I'm just feeling safe knowing that there is 50% of motor power, just in case it is needed and that all electronics can hold the stress.

[Marty Backe]

5 hours ago, TomOnWheels said:

How many of you are climbing this kind of hills on a daily (or even weekly) basis ? It's a test, just to put the wheel to its limits, and see how much it can gives. It's not something user will do every days I guess. I probably never pushed my KS18L to that temperature in all 4000km I did on it...

I do these rides to test the limits of the wheels. They are not meant to represent what most people do (but I do ride my wheels on this trail for pleasure too).

So it can be useful to know how the wheels react when they overheat and what kind of power (and low-speed torque) they have relative to other wheels.

Edited April 15, 2019 by Marty Backe

[FlyboyEUC]

5 hours ago, TomOnWheels said:

How many of you are climbing this kind of hills on a daily (or even weekly) basis ?

I ride daily up/down 22° inclines. Elevation changes of 400 ft. I've never seen my temperature get above 46°C (I haven't checked very often either). I also ride exclusively above 25 MPH with the neoprene cover from @The Fat Unicyclist. I've often wondered if the cover makes the wheel get hotter. Has any testing been done in regards to that? I guess its been winter for many people. 

Edited April 15, 2019 by Flyboy10

[Flying W]

These wheels are so sealed up from the outside world that the lay man in me thinks the larger mosfets in the MSX just have less resistance so they make less heat. 

It will be interesting to see how the nicola does with the smaller mosfets. So far all the wheels with smaller mosfets get pretty heated on that climb. 

[Marty Backe]

2 minutes ago, Flying W said:

These wheels are so sealed up from the outside world that the lay man in me thinks the larger mosfets in the MSX just have less resistance so they make less heat. 

It will be interesting to see how the nicola does with the smaller mosfets. So far all the wheels with smaller mosfets get pretty heated on that climb. 

I think that is the consensus 

[meepmeepmayer]

Don't the latest KS boards use the TO247 package, too (like the MSX)? People here told me that Are the mosfets themselves "smaller"?

[Michael Tucker]

EUC Test videos of any sort are incredibly valuable and I appreciate the effort of Marty, Matias, Chooch, Alien Rides, Miami Ron and everyone else who post Test/Fail vids.

I'd really like to see Marty do this same exact test with a different KS18XL. Perhaps a local friend's wheel. These temps seem too high to be believable for such a short ride. I have a KS18L that I ride on and off-road (steep stuff in SF Bay Area and Santa Cruz Mountain base) and never saw the temperature above 70C. Is my wheel a fluke or his? 

[Flying W]

1 hour ago, meepmeepmayer said:

Don't the latest KS boards use the TO247 package, too (like the MSX)? People here told me that Are the mosfets themselves "smaller"?

I thought I read that the 16x would have the 247s too, but that would be they didnt just drop in the 18xls board. Will be really cool if they use the 247s!

[Marty Backe]

52 minutes ago, Michael Tucker said:

EUC Test videos of any sort are incredibly valuable and I appreciate the effort of Marty, Matias, Chooch, Alien Rides, Miami Ron and everyone else who post Test/Fail vids.

I'd really like to see Marty do this same exact test with a different KS18XL. Perhaps a local friend's wheel. These temps seem too high to be believable for such a short ride. I have a KS18L that I ride on and off-road (steep stuff in SF Bay Area and Santa Cruz Mountain base) and never saw the temperature above 70C. Is my wheel a fluke or his? 

These are long steep hills that I'm riding. The kind of hills where it's marginal that you have enough power to climb. Is that the kind of riding that you're doing?

I'll have to see if @Rama Douglas would be interested in riding with me on these same trails. Him on his production XL and me on the pre-production XL. Would be very interesting. We are both in the general ballpark, in terms of weight.

[fryman]

10 minutes ago, Marty Backe said:

These are long steep hills that I'm riding. The kind of hills where it's marginal that you have enough power to climb. Is that the kind of riding that you're doing?

I'll have to see if @Rama Douglas would be interested in riding with me on these same trails. Him on his production XL and me on the pre-production XL. Would be very interesting. We are both in the general ballpark, in terms of weight.

I would agree; another test with a different wheel would be a good idea. The temps seem really high.

[Unventor]

19 minutes ago, Marty Backe said:

These are long steep hills that I'm riding. The kind of hills where it's marginal that you have enough power to climb. Is that the kind of riding that you're doing?

I'll have to see if @Rama Douglas would be interested in riding with me on these same trails. Him on his production XL and me on the pre-production XL. Would be very interesting. We are both in the general ballpark, in terms of weight.

I really think that would be a very interesting test to do.

I know from my company that pre production model (we call these mt samples)  do not have same performance as production units. It is about hand assembled vs factory assembled.