Inmotion V13 Speculation

[techyiam]

5 minutes ago, LeGiroquoi said:

I think the market could benefit from a company that would make quality.

The V13 is a well made wheel that also has advanced safety features.

The sales number at EEVEES and smartwheel.ca indicate that the Sherman-S is out selling the V13.

Time will tell whether the V13 was a success or not?

 

[Uras]

1 hour ago, techyiam said:

This is true until the time when the wheel does a high speed cutout, faceplants the rider, and the rider incurs a big medical bill, that is if the rider does not die first.

90 km/h top speed is in the big league now, where they play for keeps.

isn't this a problem with inmotion too? Inmotion seem to have their fair share of faults. Perhaps you're really trying to comment on build quality which is a different thing; it appears you can have a quality build with design or component / firmware faults too. Inmotion appears to be every bit as dangerous as other brands when they release new models.

Edited January 31, 2023 by Uras

[Uras]

8 minutes ago, LeGiroquoi said:

Less crappy designs and more bells and whistles

ahh, we're all different. I never want bells and whistles. I want simple and reliable and high torque. For me bells and whistles are just extra stuff to go wrong. 

[UPONIT]

12 minutes ago, techyiam said:

I believe one error Inmotion made with the V13 is not giving it 3600Wh battery capacity. 

The Sherman Max was the best selling big wheel, and it had 3600 Wh battery. There were also the Monster Pro, S20S, and Commander with 3600 Wh battery. In group rides, there will be too many 3600Wh wheels to contend with.

If Inmotion made a wheel with the same performance and handling characteristics as the Commander Pro, but without the flaws, and instead give it decent build quality and QC, not overboard though. I wonder if that would become a best seller.

No. Because people would bitch about the weight. Also, the wheel isn't even out yet. How do we know how well it will sell? Out of 250,000 EUC riders worldwide, 95% don't make YouTube videos or post online. The people we hear from are the outliers, not the average.

Remember the Simpson's episode where Homer designed a car that tried to please everybody in every way?

TV is very wise.

[GHOSTTE]

27 minutes ago, techyiam said:

The sales number at EEVEES and smartwheel.ca indicate that the Sherman-S is out selling the V13.

Time will tell whether the V13 was a success or not?

The issue is the V13 was released when the Sherman S came out with the new hotness, hydraulic suspension. Why buy something with older style air suspension and a smaller battery when the Sherman S has new tech and more range while at the same time lighter. If the V13 had been released 6 months earlier it would have better sales but releasing at the same time as the Sherman S was a bad call.

[techyiam]

3 minutes ago, GHOSTTE said:

The issue is the V13 was released when the Sherman S came out with the new hotness, hydraulic suspension. Why buy something with older style air suspension and a smaller battery when the Sherman S has new tech and more range while at the same time lighter. If the V13 had been released 6 months earlier it would have better sales but releasing at the same time as the Sherman S was a bad call.

But that is still performance trumping over build quality and safety features, except in this case, it is suspension performance. 

Inmotion is going to lose playing the build quality and safety features cards. What you saying is that the V13 will lose when competing head to head.

The market has spoken.

[GHOSTTE]

8 minutes ago, techyiam said:

But that is still performance trumping over build quality and safety features, except in this case, it is suspension performance. 

Inmotion is going to lose playing the build quality and safety features cards. What you saying is that the V13 will lose when competing head to head.

The market has spoken.

Pretty much. Hydraulic suspension is more appealing to anything the V13 offers I'd imagine to a lot of people

[chanman]

2 hours ago, UPONIT said:

Again, higher voltage allows for smaller wiring, less copper, etc. without increasing resistance

This is vaguely correct, however I'm specifically talking about the efficiency of the mosfets, which are higher resistance when rated for higher voltages, thus less efficient on the V13 than previous wheels. They are claiming they are safer because there's much more buffer between the breakdown voltage and the system voltage, but I'm waiting for data on failure rates to back that up. They are higher resistance than equivalent 150V parts.

Edited January 31, 2023 by chanman

[HEC]

2 hours ago, techyiam said:

I believe one error Inmotion made with the V13 is not giving it 3600Wh battery capacity. 

The Sherman Max was the best selling big wheel, and it had 3600 Wh battery. There were also the Monster Pro, S20S, and Commander with 3600 Wh battery. In group rides, there will be too many 3600Wh wheels to contend with.

I disagree. Not everyone uses the EUC (primary or at all) for group rides. In fact, I'm pretty sure that vast majority of EUC owners use it for daily commute, as last mile transportation (probably not V13 that much for later) or simply for fun on their own or perhaps within family or with friend or two, and will be perfectly happy with the performance, comfort, range and most of all safety of V13 (or basically any other Inmotion wheel). I see no point in Inmotion trying to imitate other EUC makers. The benefit of the competition is that there is EUC type / model for every need or type of use / user.

Plus Inmotion is one of the OG players on the market with much more experience in producing various PEVs, not only EUCs, years before the currently "popular" dogs. And it shows on their dedication to safety, design and quality. Numerous EUC manufacturing companies are out if business now, all of them starting way after Inmotion (apart of Solowheel). Inmotion are in it for a long run, not just for a quick buck and disappearing act in couple of years. Yes, they had their share of issues but AFAIK they faced them and handled those way better than any other manufacturer.

Any serious EUC user will have at least 2 or 3 wheels to cater for majority of their use scenarios, and those who can afford (or prefer to have) only one, will simply choose the wheel most suitable for their main intended purpose and will be still able to use it for the rest as well. Finally, the amount of users regularly riding over 80 (or even 60 - 65) Km/h is yet again a fraction of overall user base. 

Edited January 31, 2023 by HEC

[Mango]

Inmotion is always stingy with battery capacity. However, their wheels sell well and most of the buyers don't post to social media.

What we see is a social media echo chamber of performance wheels and Begode products, but the real world is much different.

Inmotion, please continue doing you.

[Clem604]

2 hours ago, techyiam said:

I believe one error Inmotion made with the V13 is not giving it 3600Wh battery capacity. 

This is the camp I'm in. After riding it my ONLY gripe (at the time) was that it lacked the battery capacity I was looking for since I like to go for super long rides. For the people who don't need the range of a 3600wh wheel then the V13 would be a great choice IMO.

[Paul A]

2 hours ago, UPONIT said:

250,000 EUC riders worldwide,

What is the data source of 250k riders?

 

2 hours ago, UPONIT said:

95% don't make YouTube videos or post online.

How is this determined?

 

Thanks.

[Paul A]

2 hours ago, techyiam said:

The sales number at EEVEES and smartwheel.ca indicate that the Sherman-S is out selling the V13.

 

Why is IM wanting to emulate BG....instead of LK?

 

IM is wanting to emulate BG, in releasing many models of low quality?

[soulson]

6 hours ago, chanman said:

The efficiency part has to do with the Drain-Source on resistance, which is higher on smaller and higher voltage rated components. However putting such a large number in parallel effectively is reducing the losses, since less current is through each chip. I guess I'll need to wait for part numbers and do some math to be sure.

Has to do with R_DS(on), yes, but based on my napkin math, only about 6W is being dissipated across all 42 transistors under an instantaneous load of 10kW across the motor due to R_DS(on). I think a more significant contributor to losses across the transistors in the controller would be the rise and fall times of the FETs. During some number of nanoseconds, the transistor transitions from effectively infinite ohms of resistance down to 9.5 milliohms as a continuous function of time. At some instant on that continuous function, the whole 126V are across the transistor's drain-source junction while the drain-source resistance of the transistor equals the sum of the resistances of the battery and motor plus the instantaneous reactance of the motor. At that instant, half of the power of the system (disregarding current flowing through transistors in parallel) is being dissipated across that transistor. If maximizing efficiency is a goal, then using "fast" transistors can make a big difference.

5 hours ago, chanman said:

Awesome, unfortunately I get absolutely nothing when I search those or a few close strings, so maybe something obscure or too Chinese to show up on my electronics sites or google.

Let me help (thanks to ecodrift and Inmotion for providing the datasheet on this FET): https://ecodrift.ru/wp-content/uploads/2023/01/hgp098n20m_v1.0.pdf

This FET has a low R_DS(on) but relatively slow t_d(on) and t_d(off) compared to the FETs I'm used to working with, which could be part of why testers are showing the V13 to be somewhat inefficient. Then again, testers have also been saying that the inverter board doesn't need any active cooling, so I'm disinclined to believe that "25% less range" is strictly down to controller efficiency. That waste heat would have to go somewhere.

Ultimately, that's probably the thing I find most interesting thing about the relatively low "meters per watt*hour" of the V13. If it truly has such poor efficiency, then that waste heat would have to go somewhere. Where's it going?

Edited January 31, 2023 by soulson
clarifying

[techyiam]

42 minutes ago, Paul A said:

IM is wanting to emulate BG, in releasing many models of low quality?

That is a good question. According to Dawn, that was the question discussed between them.

I can only surmise Begode sells a lot of units across their many models.

And Leaper Kim only has the Sherman Max, and now Sherman-S. So, perhaps Begode is more successful than Leaper Kim. 

[techyiam]

1 hour ago, HEC said:

I disagree. Not everyone uses the EUC (primary or at all) for group rides. In fact, I'm pretty sure that vast majority of EUC owners use it for daily commute, as last mile transportation (probably not V13 that much for later) or simply for fun on their own or perhaps within family or with friend or two, and will be perfectly happy with the performance, comfort, range and most of all safety of V13 (or basically any other Inmotion wheel). I see no point in Inmotion trying to imitate other EUC makers. The benefit of the competition is that there is EUC type / model for every need or type of use / user.

Just you know, I was specifically addressing the V13.

I don't have access to actual data. Bob ask Dawn this very question, and she deferred the question to Marty. This is the CEO of Inmotion that we are talking about. There is no way he would be putting out feelers regarding range for big fast wheels if he doesn't feel there is a possibility that this could be an important factor.

My own opinion based on what I glean from social media for the US market is that there is a good probability that competitive range is an important factor in how well big fast wheels sell in the US. And the V13 is a big fast wheel.

[chanman]

For anyone struggling with the markings in the picture earlier, the intended marking string is apparently GB098N20M, which does get the hit on the ecodrift page.

Just to put some perspective, the R_DS(on) for the JMSH1504AS, the 150V chip in the S22 is roughly half of these chips, but with only 2 in parallel. I'm doing some math now and I think the 7 parallels HGB098N20M actually wins out for lower R_DS(on) power consumption, but either way it is a single digit number of watts for even a large amount of current.

1 hour ago, soulson said:

I think a more significant contributor to losses across the transistors in the controller would be the rise and fall times of the FETs

I hadn't considered this, I guess it's somewhat an interesting exercise. I don't know the switching frequency used but we could calculate a percentage of time the fets are actually switching to see if handful of nanoseconds switching are significant. I also wonder if they are always perfectly synchronized to the handful of nanoseconds, if one of the 7 parallels turns on early more of the current goes through that and the others being partially turned on won't matter much.

Edited January 31, 2023 by chanman

[Uras]

2 hours ago, Mango said:

What we see is a social media echo chamber of performance wheels and Begode products, but the real world is much different.

Geez, they are the real world. They are people who ride test wheels and show us what they choose to ride (and buy) themselves. I'm pretty sure that if they preferred inmotion or whatever that they would be riding them. We see that in their group rides - how random dudes like whatever wheel when they're trying them out. I ride with a pev group once a month or so; out of 9 euc riders only one of them has an inmotion (v11). I ride a ks16x - maybe I have a bias too . My choice right now would probably be s22pro or t4 - although I'd prefer to wait till potential issues were sorted. I have no need or desire for a 50kg behemoth where I ride. People like what they like, despite what you think or believe. There seems to be a real inmotion bias in this forum - I don't get it.

Edited January 31, 2023 by Uras

[techyiam]

1 hour ago, soulson said:

If it truly has such poor efficiency, then that waste heat would have to go somewhere. Where's it going?

I think you make a very good point.

The only moving parts in a non-suspension wheel are the wheel bearings and the tire / motor assembly. Regarding range, these items don't factor in significantly plus, it would be the same for another wheel. And for suspension wheels, the suspension movements also don't affect significantly the consumption of battery energy.

What is left is the waste heat generated by the motor, and the components on the controller board, mainly the mosfets.

What other factors can there be to explain the discrepancy of 25%? The batteries themselves? 

Also, Marty has observed that the V13 doesn't run particularly hot, and I read that early on he said, he hasn't heard the fan come on unless the headlights are on.

 

Edited January 31, 2023 by techyiam

[2disbetter]

6 hours ago, techyiam said:

According to Dawn in her live chat, Bob, the CEO of Inmotion contacted Dawn and spoke to her for about an hour and a half. Among the things they talk about was the idea that Inmotion would back away from quality and follow Begode's footsteps.

I think this would be a real tragedy. Like Kuji and Hsiang say in their videos, this wheel from Inmotion, and Inmotion's stance on quality is crucial for the momentum that EUCs need to gain popularity. Enthusiasts who are speed junkies are not interested in sustainability or longevity. They are just looking for the next adrenaline rush. 

Like Kuji says in his video, I don't want a fire in my home, and I don't want my wheel killing me because of a failure. Wheels that go this fast MUST prioritize quality and safety. We are one horrific crash away from these things being outlawed. 

[2disbetter]

6 hours ago, UPONIT said:

I'd love to hear more of what you think about the suspension. The reactions to it are all over the place. You actually own the wheel.

FWIW, I ride my V12ht way more than I ride my V11. I do see the usefulness of suspensions, even though I doubt I'll ever be a jumper.

Still, one of the things that caught my attention about the V13 is that the suspension is so easily removable. That's a very nice touch. Making it easy to adapt to different situations.

I have to preface anything I say with the fact that I've been riding since the beginning of Jan this year. I have a V12 HT and I have a V13. Both of these wheels scream quality and polish. Things like battery cables flopping around and falling off while people eww and ahh about the EBCP blows my mind. The fender on the thing broke off and was crocked and yet the ewwwing and awwwing continued. Why? Because these are adrenaline junkies. Awesome and nothing wrong with it. I'm one too, but please don't use impressions from them to form opinions about anything. (You hear that Inmotion CEO? You are doing it right. Don't falter!!!!) They would ride a duck taped wooden wheel with a rocket on it and talk about how it is the greatest wheel known to mankind. Hopefully you see what I mean. 

 

The V13 as compared to the V12 HT is super stable. Way easier to hop on and go. But turning, especially at slower speeds, as both Kuji and Hsiang mentioned, takes more effort. This gives you the impression that it is not as agile. I'm finding that it is, I just can't be lazy. The suspension on mine still needs to be dialed in. To me it is still too hard. I think I need to let out about 20 psi. But even as is, I'm not worried about bumps, and am not always trying to avoid them like on the HT. My feeling on the suspension is that I'm glad it is there. Is it the best? Most likely not, but it makes the wheel better for being there. The fact that you can remove it and lock the travel out, and they include the stuff necessary to do that in the wheel's packaging, is just further evidence of their quality and polish. Everything about this wheel screams quality. I am not wondering why it costs what it does. 

One other thing I can note, is that both of my wheels accelerate fast, but the V13 does it faster. Furthermore, you are more aware of just how fast your accelerating because of how much mass is moving with you. (NOTE: The V13 has 220 ft lbs or 300 Nm of torque. Does ANY other wheel come even close?)

I have only experienced Inmotion wheels. I originally wanted a Sherman. Ewheels wouldn't deliver it to me. (not their fault) So it went to my brother in Georgia. I would like to try other wheels, of course, but I would absolutely buy the V14 if Inmotion stays the course they are on now. I can see myself being team Inmotion for a long time. 

Edited January 31, 2023 by 2disbetter

[techyiam]

13 hours ago, 2disbetter said:

I think this would be a real tragedy. Like Kuji and Hsiang say in their videos, this wheel from Inmotion, and Inmotion's stance on quality is crucial for the momentum that EUCs need to gain popularity. Enthusiasts who are speed junkies are not interested in sustainability or longevity. They are just looking for the next adrenaline rush. 

If the CEO of Inmotion is asking this type of questions for feedback, it doesn't look good. The thing is, Inmotion is a business,  not a charity.

13 hours ago, 2disbetter said:

Like Kuji says in his video, I don't want a fire in my home, and I don't want my wheel killing me because of a failure. Wheels that go this fast MUST prioritize quality and safety. We are one horrific crash away from these things being outlawed. 

The Master sold very well. Look at the battery packs, and BMS's. Unbelievably cheap. And no weather proofing. 

But no, when it come time to make a preorder, or purchase, more often than not, the purchaser click on a Begode wheel.

The owner of Rev Rides have said Begode wheels have sold very well in California. Look at the best sellers at Alien Rides.

People talk the talk, but not walk the walk. 

Bottom line. Performance trumps build quality and safety. 

Kingsong did a Gotway and their S22, and it is among the best selling wheels. 

Begode builds a quality wheel, the Hero, and lost miserably. 

 

Edited January 31, 2023 by techyiam

[2disbetter]

14 minutes ago, techyiam said:

Bottom line. Performance trumps build quality and safety. 

This might be, but what people really want is all of those things. If the V13 was the fastest in all metrics, it would be the sales winner. 

The interesting thing is that the V13, from a hardware standpoint, is positioned to do all of those things. We are a firmware update away from things being increased on it. 

The wheels that are competing against it are already going to their hardware maxes. There isn't any more room for them to improve without a hardware revision. 

This is not the case for the V13. 

[techyiam]

5 minutes ago, 2disbetter said:

This might be, but what people really want is all of those things. If the V13 was the fastest in all metrics, it would be the sales winner. 

Nope. People will then complain about the price, weight, or both.

6 minutes ago, 2disbetter said:

The interesting thing is that the V13, from a hardware standpoint, is positioned to do all of those things. We are a firmware update away from things being increased on it. 

Nope. That would mean Inmotion has to cross over to the Dark Side and relax safety margins. 

Top speed crown is not really a thing, but some people make it so.

Inmotion already has a "safe" top speed of 90 km/h. There aren't that many opportunities to reach those speeds for most owners. But the heart wants what the heart wants.

Moreover, Begode will always build something faster in response anyway. Inmotion won't be able to compete. Begode has a 146-volt system waiting in the wings too.

18 minutes ago, 2disbetter said:

The wheels that are competing against it are already going to their hardware maxes. There isn't any more room for them to improve without a hardware revision. 

I would speculate that should Inmotion increase the top speed in firmware, Begode would announce a wheel that is faster the next day.

[soulson]

1 hour ago, chanman said:

Just to put some perspective, the R_DS(on) for the JMSH1504AS, the 150V chip in the S22 is roughly half of these chips, but with only 2 in parallel. I'm doing some math now and I think the 7 parallels HGB098N20M actually wins out for lower R_DS(on) power consumption, but either way it is a single digit number of watts for even a large amount of current.

I hadn't considered this, I guess it's somewhat an interesting exercise. I don't know the switching frequency used but we could calculate a percentage of time the fets are actually switching to see if handful of nanoseconds switching are significant. I also wonder if they are always perfectly synchronized to the handful of nanoseconds, if one of the 7 parallels turns on early more of the current goes through that and the others being partially turned on won't matter much.

I agree, the V13's seven parallel FET arrangement should be more efficient than the S22's two parallel FETs based on R_DS(on):

S22:
R_DS(on) = 4.9 mOhm
Parallel devices = 2
Total resistance = 4.9 mOhm / 2 = 2.45 mOhm

V13:
R_DS(on) = 9.5 mOhm
Parallel devices = 7
Total resistance = 9.5 mOhm / 7 ~= 1.357 mOhm

For any non-engineers following along, a lower resistance FET arrangement is better. The power ends up getting "used" wherever the resistance is – whether that thing can do useful work with it or not. If it can't do something useful, then it just gets hot. You don't want that thing to be the inverter, nor the battery. You want it to be the motor, because that's where useful work can be done.

Interestingly, the V13's FETs are also faster than the S22's FETs, so they should be more efficient based on the rise and fall time of the PWM, too. Unfortunately, we can't figure out what the efficiency of that process is without knowing the carrier frequency of the inverter. It's a balancing act, because if the frequency is too low, the FETs will run cool and efficiently, but the distortion in the inverter's output waveform will cause heating (inefficiency) in the motor's stator windings. Contrariwise, running the frequency too high will result in a smooth, relatively undistorted waveform that will make the motor run cool and happy, but it will make the FETs start sweating as they have to slew across the resistance function more often.

1 hour ago, techyiam said:

What is left is the waste heat generated by the motor, and the components on the controller board, mainly the mosfets.

What other factors can there be to explain the discrepancy of 25%? The batteries themselves? 

Also, Marty has observed that the V13 doesn't run particularly hot, and I read that early on he said, he hasn't heard the fan come on unless the headlights are on.

Yes, the battery is part of it. The battery has an internal resistance (you may also hear it called "equivalent series resistance" or ESR in engineerese), and any current drawn by the load attached to the battery must cross the battery's internal resistance, wasting power and producing heat. This is why the battery gets warm when it is used or charged (the current flows across the internal resistance when charging, too, just in the other direction). Indirectly, this is also the cause of "voltage droop" when the battery is under heavy load. All other things being equal, a battery with lower internal resistance will be more efficient and less susceptible to voltage droop.

Summing up...

• The controller is probably pretty efficient. If it wasn't, it would get hot, which it doesn't. So this probably isn't where the perceived low efficiency is coming from.
• The battery's calculated internal resistance is 225 mOhm (based on 60 mOhm cells in a 30S8P configuration). If the total system power is 10kW, 1.4kW is being wasted as battery heat (based on P=I^2*R). So we can think of the battery as being "86% efficient". I'm not sure how this compares to other wheels, but it sounds reasonable to me as a gut check. Even if other wheel batteries were 100% efficient (they're not), then this wouldn't result in the V13 getting 25 to 30% less range per watt*hour.
  • source: https://lygte-info.dk/review/batteries2012/Samsung INR18650-35E 3500mAh (Pink) UK.html
• The motor may be efficient or not. We don't know. If the problem is literally power efficiency, then the motor is probably the culprit.

There are a few other things that could be causing this that are not literally power efficiency:

• The V13 is heavier and therefore takes more energy to accelerate. Certainly a factor, but probably doesn't explain 25%.
• The V13 batteries are potted and therefore the cells are more exposed to the external temperature than on other wheels with similar capacity. Lithium ion cells have a sort of "preferred temperature range" where their energy density is highest. They like to be warm, but not hot. If it's very cold out, then the thermally conductive potting material may be cooling them off more than they'd like, reducing their ability to hold charge. It didn't look very cold in Marty's video, though. I doubt this is a major factor.
• The V13 may have a different "zero point" than other wheels. If wheel A says that a cell is fully discharged at 3.0V, but wheel B says that a cell is fully discharged at 2.9V, then wheel B will get a full watt-hour of extra energy out of that cell. If wheel A happens to be a V13 with 240 cells, then it would hit "0% charge" with 240 more watt-hours "left in reserve" than wheel B. Given Inmotion's behavior such as limiting charge to 4.185 volts per cell, I wouldn't be surprised to learn that they also limit discharge in a similar manner, although I have no evidence of this. A difference of just 0.1 volts per cell would result in a ~10% reduction in range. The benefit to this would be battery longevity. Lithium-ion cells will perform better over time if they're not discharged super deep.

Edited January 31, 2023 by soulson
corrected typos