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New GotWay Nikola 17''


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14 hours ago, Marty Backe said:

I have no engineering insight to Gotway's solution, but to say go with the bigger MOSFETs "just because", feels a bit like a religious argument. Unless we are provided with the schematics of their circuit design we don't have much basis for an argument, unless the new wheel starts burning up control boards.

We just need to find some Gotway early adopters :ph34r:

I understand what you're saying. At the same time I come to think of a quote attributet to Alan Shepard when he crawled into the space capsule: "Just think, the contract on this thing went to the lowest bidder."

So what I'm after is something of a mindset change, where the minimum specs for not failing for 99% of the users ain't good enough. That may lead to some ridiculous over-engineering, but will on the other hand change our perception of the capabilities of the EUC.

Think for example about the difference climbing with your MCM and the Monster. Is it impossible to build a 22" wheel with the climbing abilities of your MCM? A Monster that could take on your overheat hill without even be close to overheating, and that would have all the torque you could ask for?

Of course it isn't impossible. It is just a matter of where you set your target when you design the EUC and spec the components. It might be more expensive, that is true, but I'm not sure the difference would be that monstrous (sorry for the pun). Add a few hundred dollars in copper, MOS, cooling, water-proofing... Design the pedals, pads, shell, and so on not only for looks, but for maximum stability, leverage and comfort. And use the "smart" firmware to give that extra power when needed, while keeping the energy consumption under control under normal use.

Just look at the difference between a 67V MSuper, or a KS16B on one hand, and the MSX and the KS18XL on the other. Just a few years, and this is how far we've come. The new wheels are faster, safer, stronger and runs cooler. Let's continue on that tangent.

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3 hours ago, Scatcat said:

I understand what you're saying. At the same time I come to think of a quote attributet to Alan Shepard when he crawled into the space capsule: "Just think, the contract on this thing went to the lowest bidder."

So what I'm after is something of a mindset change, where the minimum specs for not failing for 99% of the users ain't good enough. That may lead to some ridiculous over-engineering, but will on the other hand change our perception of the capabilities of the EUC.

Think for example about the difference climbing with your MCM and the Monster. Is it impossible to build a 22" wheel with the climbing abilities of your MCM? A Monster that could take on your overheat hill without even be close to overheating, and that would have all the torque you could ask for?

Of course it isn't impossible. It is just a matter of where you set your target when you design the EUC and spec the components. It might be more expensive, that is true, but I'm not sure the difference would be that monstrous (sorry for the pun). Add a few hundred dollars in copper, MOS, cooling, water-proofing... Design the pedals, pads, shell, and so on not only for looks, but for maximum stability, leverage and comfort. And use the "smart" firmware to give that extra power when needed, while keeping the energy consumption under control under normal use.

Just look at the difference between a 67V MSuper, or a KS16B on one hand, and the MSX and the KS18XL on the other. Just a few years, and this is how far we've come. The new wheels are faster, safer, stronger and runs cooler. Let's continue on that tangent.

I hope to pass on my observations to those who would listen and I hope the manufacturers are listening...  If you look a motor, the airgap is where the turning force is.  It is at the edge of the motor.

injection_statorade.jpg.9edbd1ba12b667b0c105f33bd44af656.jpg 

If you look at the monster wheel, look at all the space between the rim and the motor edge (where the turning force is).  They currently just reuse the same motor and add spokes and tire to make the wheel bigger. 

This has two advantages:

1) cheaper, one part the motor is all shared

2) allows for more top speed.  bigger outer diameter per rotation given the same motor and same V/rpm, more distance per rotation.

disadvantage is huge:

1) bad at climbing hills

2) hesitation that is felt when changing directions or accelerating.

 

This is all physics, just try turning a bike wheel from the center vs from the rim.  It is much easier turning it from the rim. 

If they make a properly sized motor for the 18" or 22", it will not be as fast, but it would be a fantastic wheel!  I'm hoping someone will design a motor that is bigger, properly sized to 18" with some lighter materials so it would be no heavier than a 16" wheel.  To overcome the slow down, they must increase the voltage.  maybe to 120v or something like that.  

Fingers crossed it will come in the next year or two. My favorite size is the 18" and if the motor is sized and weighted correctly should be the only wheel anyone needs.

 

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It was always the top mosfet that would explode or short. now with the new types we know pretty well that they wont care how much or how hard you run the wheel.
msx is the first wheel i felt safe on at high speeds or up steep hills. I believe they should stick with that going forward. i also hope the current-limiting is done better this time around..

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@eddiemoy Do you know for sure if it makes a difference how the motor is built? The torque depends on the outer diameter anyways. So unless a bigger motor is somehow more efficient or you can have better suited windings in a bigger space (more windings = less top speed, more torque, I believe), I can't quite decide if there should be a difference. In the end, energy goes in and torque goes out at a fixed radius.

And whenever I see extra strong (high torque) electric motors, it's these tiny hub motors. So I had the impression that maybe even small=stronger/better for technical reasons. But maybe that's just how they save on material cost.

Do you have any definitive knowledge to illuminate the issue?

40 minutes ago, EUC GUY said:

msx is the first wheel i felt safe on at high speeds or up steep hills. I believe they should stick with that going forward.

Yes, that's what was so nice about the TO-247s. You didn't have to trust Gotway, you knew (thanks again for your car test btw) that they will hold up under pretty much anything, and will throw a temperature/overheat warning under all realistic high stresses (like your mountain tests). Very freeing.

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5 minutes ago, meepmeepmayer said:

Yes! Overengineer everything, and monitor the weakest point. Easy to do for the manufacturer, good and safe and strong wheel. That was kind of GW's USP with the new/MSX board. I wonder why they changed their mind, if they really did...

Hehe easy fix there you go 500w motor...15kmh top speed...

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56 minutes ago, meepmeepmayer said:

@eddiemoy Do you know for sure if it makes a difference how the motor is built? The torque depends on the outer diameter anyways. So unless a bigger motor is somehow more efficient or you can have better suited windings in a bigger space (more windings = less top speed, more torque, I believe), I can't quite decide if there should be a difference. In the end, energy goes in and torque goes out at a fixed radius.

And whenever I see extra strong (high torque) electric motors, it's these tiny hub motors. So I had the impression that maybe even small=stronger/better for technical reasons. But maybe that's just how they save on material cost.

Do you have any definitive knowledge to illuminate the issue?

Yes, that's what was so nice about the TO-247s. You didn't have to trust Gotway, you knew (thanks again for your car test btw) that they will hold up under pretty much anything, and will throw a temperature/overheat warning under all realistic high stresses (like your mountain tests). Very freeing.

I cannot teach you, only help you see what I see with regular experiences.  

Example would be with a multi speed bike, you will know that if you use a smaller sprocket( closet to the center) on the rear it is more difficult to pedal, then when you change to a taller gear( further out from the center) in the back, it is much easier.  You didn’t all of a sudden get stronger.  You are just applying the force closer to the outside of the wheel.  

This is what I’m trying to demonstrate to you with your own experience.  

You will also notice in smaller euc, they feel much stronger climbing and accelerating.  It isn’t because of the power because the larger wheels have more power.  I used to think the motors were made for torque but it isn’t.  It’s the same shitty motor. 

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13 minutes ago, eddiemoy said:

I cannot teach you, only help you see what I see with regular experiences.  

Example would be with a multi speed bike, you will know that if you use a smaller sprocket( closet to the center) on the rear it is more difficult to pedal, then when you change to a taller gear( further out from the center) in the back, it is much easier.  You didn’t all of a sudden get stronger.  You are just applying the force closer to the outside of the wheel.  

This is what I’m trying to demonstrate to you with your own experience.  

You will also notice in smaller euc, they feel much stronger climbing and accelerating.  It isn’t because of the power because the larger wheels have more power.  I used to think the motors were made for torque but it isn’t.  It’s the same shitty motor. 

perhaps a softer pedal setting would make it easier to climb hills on bigger wheels?
As that allows you to fall further forward before the wheel accelerates, you would have more mass in front of centre. 

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18 minutes ago, EUC GUY said:

perhaps a softer pedal setting would make it easier to climb hills on bigger wheels?
As that allows you to fall further forward before the wheel accelerates, you would have more mass in front of centre. 

It is definitely the motor and where the magnets/air gap is in relation to the rim.  The closer to the rim or outside of the tire the easier it is to climb.  It would mean more magnets and windings.  Which means more switches of the mosfets to get a complete revolution of the wheel.  Means the wheel would be slower for the same voltage.  Need more voltage to maintain the same speed for the bigger motor.  

 

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3 hours ago, Jason McNeil said:

Got to agree, there's quite a bit of retrogression with the Nikola.

During my last Gotway factory visit back in February, spent a full day with the brains/owner of Gotway, Mr Lin. We spent quite a bit of time talking about the board reliability—this was in pre-TO247 MOSFET era. Lin showed me some videos of their stress-testing process, where the boards would be programmed not to cut-out on reaching max RPM, the Wheels would be spun up & held up, then flicked backwards, effectively going from max speed to reverse speed in a fraction of a second, stressing the system far more than would be experienced in any 'normal' use scenario. What was remarkable, was how the original IRFP4368s would go quite literally explode, while the HY/TO247 MOSFETs held up. Lin said that while KS, Inmotion & other manufacturers current limited their firmware, GW did not, which is the reason they still don't use fuses. Perhaps with the Nikola they've made the decision to current limit their boards as well, but the hardware shown in this preproduction Wheel doesn't look all that more substantial than a first generation 350W machines.       

This is interesting to read. So we have first hand knowledge that Gotway spends a lot of effort on this which makes me feel better about the newer engineering solution. Maybe a bad assumption, but I would assume that they did the same spinning test with the new Nicola control board and saw that it performed satisfactorily (no exploding MOSFETs).

Otherwise, by what rationale would they decide to lose the advantage they gained with the larger MOSFET design.

I guess we'll discover the truth as these wheels enter the marketplace.

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17 hours ago, Marty Backe said:

This is interesting to read. So we have first hand knowledge that Gotway spends a lot of effort on this which makes me feel better about the newer engineering solution. Maybe a bad assumption, but I would assume that they did the same spinning test with the new Nicola control board and saw that it performed satisfactorily (no exploding MOSFETs).

Otherwise, by what rationale would they decide to lose the advantage they gained with the larger MOSFET design.

I guess we'll discover the truth as these wheels enter the marketplace.

One reason can be the footprint of the board. Looking at the MSX-board in pictures (have yet to see it live) it looks a bit heftier than the earlier boards. It might be hard to fit that into a compartment at the top of the wheel. Of course that could probably be fixed with the right layout, but who knows?

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On 12/20/2018 at 2:58 AM, Hunka Hunka Burning Love said:

 Considering the cost, complexity and work to redesign a plastic shell not to mention timeline for release, my money’s on this being the final design.

Where’s @Cloud?  He speaks Russian.  Maybe he could translate?

I am back

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7 hours ago, Skeptic_7 said:

Kind of disappointed in the handle bar choice... looks uncomfortable, not sure why they chose that design

If you mean the trolley, it's actually the best design IMHO. 

In theory, the curved/scorpion trolley both

  • saves space, as there is no need to take up potential battery space in the body when retracted, and the curved trolley folded takes up the least external space, disappearing into the curve of the circular wheel body, and....
  • has no dominant / optimal pushing direction, as trolleying both front-facing and back-facing will exert the same force when pushing on the trolley end, due to the curve.

 

In practice though, unfortunately, the curved trolley hasn't been implemented quite optimally, as in the InMotion case, there is significant play at the hinge/attachment base (seems to be the same case, to a degree, on the Nikola trolley *smh), and, like many other different trolley designs, there is no height/length adjustment to factor for different rider heights / reach.

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9 minutes ago, Marty Backe said:

I have to disagree with you on this. The KingSong trolley handle is the absolute best. No other trolley handle provides the same level of wheel control. A actually think the "Inmotion" style handle is the worst of them all.

You are correct in terms of the negative affects within the shell, but from a user experience perspective, KingSong seems just about perfect to me.

Plus one here.  I think those fold up handles are the worst piece of " oh shit, we forgot to integrate (fill in the blank) into this design" I've ever seen.  Also, they are very vulnerable in a crash.  I've seen one totally destroyed in a tumble, and NineBot had breakage problems with the hinges on their version (which admittedly was more of a carry handle than a trolley handle).  Additionally I can't see any way to make a tiny hinge like that, not flex disturbingly when it's on the end of such a long handle, controlling such a big weight. Lastly  It's a very poor engineering solution, and it's ugly.  Other than that I love them.:whistling:

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1 hour ago, Marty Backe said:

I have to disagree with you on this. The KingSong trolley handle is the absolute best. No other trolley handle provides the same level of wheel control. A actually think the "Inmotion" style handle is the worst of them all.

You are correct in terms of the negative affects within the shell, but from a user experience perspective, KingSong seems just about perfect to me.

Yes, I have to agree that the KS trolley handle is the best so far.  Can’t really beat the center handle which allows for turning really easy. 

I never got used to the INMOTION handle. Even trolleying it backwards, still the leverage for turning isn’t there. 

 

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2 hours ago, Marty Backe said:

I have to disagree with you on this. The KingSong trolley handle is the absolute best. No other trolley handle provides the same level of wheel control. A actually think the "Inmotion" style handle is the worst of them all.

You are correct in terms of the negative affects within the shell, but from a user experience perspective, KingSong seems just about perfect to me.

1 hour ago, eddiemoy said:

Yes, I have to agree that the KS trolley handle is the best so far.  Can’t really beat the center handle which allows for turning really easy. 

I never got used to the INMOTION handle. Even trolleying it backwards, still the leverage for turning isn’t there. 

Both of you are suburb car guys, no reason to extensively lift and carry the wheel. (I don't own a car by design, no need to)

I'm gonna wait and see how the urban walk-up apartment guys KS18L/XL handles last after over a year of the substantial 18L/18XL weight stress. I don't have much faith in how tiny the screws supporting them are at the bases of the grab handle, even with the redesigned fix (don't believe me? just unscrew one and take a look, see if you have faith in those two thin screws supporting over 50+lbs over time).

If the KS trolley had an accompanying, solid, built-in-to-the-shell grab handle, this would be a different argument.

 

Also, neither of you have extensively used the scorpion trolley design (again, not being in a daily urban setting) for more than just a demo or few months, as @Marty Backe you don't own one, and @eddiemoy you said it yourself, you barely use your now-on-sale V10F, let alone come into the city from Jersey for non-car-attached daily riding.

While yes, minus my above KS handle concerns, the diagonal KS trolley design I'd say would be #2, I've used the IM scorpion trolley on my V5 for over a year of ownership, day-in-and-day-out....

 

..... and I respectfully disagree. 

 

No other trolley has allowed me to twirl around as easily my wheel with one hand in circles like the scorpion design can, not even the KS-style trolley (handle is too wide, whereas the scorpion trolley is easily manipulate-able in one hand grabbing the narrow bulb end).

If I did the same with the super crappy perpendicular style MSV3/MSX trolley, I would drop the wheel, not to mention trolleying those wheels normally is un-weildly in general IMHO. You can't really tell me that's better than the curved design (not to mention, the curved trolley locks in place (well, with some wiggle), whereas the MSV3/MSX trolley does not, can, and has flown out on impact (thus bending) for some of our NYC riders).

If these real world implementations actually did the curved design justice (way less joint wiggle; collapsing length), there would be no question to me that the scorpion trolley would be by far the best, speaking from someone who constantly has to use his in an urban setting.

Edited by houseofjob
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