Poll: Have you experienced an unexpected shut-off while riding?

[Chriull]

On 4. April 2016 at 8:10 AM, tjcooper said:

Finally got proof of the good "unexpected stops" on video.

 ...

There are minor cracks in the asphalt in the park surface.  But I rode many circles over all the minorcracks and I could sense that I had gone over them as a slight pull to left or right, but nothing that changed my balance.

 ...

Battery was full at start.  After the 25 minute session, the battery was down one bar. 

...

and I was never faster than 5-7 mph (fast walk).  I think this strongly points to a failure of battery after 20% discharge. 

Could it be, that driving with "supporting wheels" causes problems if there are minor cracks? I assume they could introduce quite some torque if they happen to get a resistance - they are small and have a "strong leverage to the system". Especially with low speeds when there is no kinetic energy in the system which could overcome minor disturbances?

But i never drove with supporting wheels - so i do not know if my above thoughts make any sense - they are just a guess. I just know that driving slowly is one of the harder things to learn - in the beginning i always needed to get some speed for beeing able to drive.

On 4. April 2016 at 8:10 AM, tjcooper said:

NEW PROBLEM:  In the previous video I showed how hard it was to restart the MoHoo after the fall.  People on the forum said I had just forgotten to reset-restart the unit after the fall.  I could swear I had done that and that the unit would not hold true level.

In the latest sets of video, I made ABSOLUTELY sure to turned off the unit and then back on before I attempted to remount.  As you can see from the new videos, I still have significant problems restarting after a fall.  What I found out was that I had to wait 10-15 seconds after the “off” push when I stood up,and then push the “on” button and test that the system holds level.  If I tried to do the “on” buttonfaster than the 10-15 second delay, the system would not obtain level running when I pushed the handle forward and backward.   Could this mean that there is some sort of software problem after a hard shutdown that needs time to reset before the system would perform normally again.  I believe this is a repeatable phenomenon after a hard stop has occurred (power overload?).  This might point to the problem being in the motherboard.

    tjcooper

A (hard) shutoff would mean that you cannot turn the wheel on again at all! You would have to connect it to the charger before you can use it again (or dis and reconnect the battery pack). If you can restart a wheel after a "shutoff" this is normally some kind of overchallenging the wheel or just a Controller board fault. since you are not overchallenging the wheel by overleaning or thermal issues my best guesses would be either the supporting wheels or the controller fault.

But as with the restarting issues this seems like a real controller problem, you should just look for a refund!

Theoretically this also could be an undervoltage shutoff, which could also cause the troubles when trying to turn the wheel on  - this just works once the batteries regenerated enough voltage again. But i doubt somehow that as bad batteries would recover enough within 10-15 seconds - but behaviour of stressed batteries and their regeneration is a topic i would be very interested in but lack quite any knowledge about:(

Anyhow - again a reason to return the wheel. And imho the strongest reason should be that driving with a wheel and just waiting for an accident is pure stress and no fun! I would not drive a wheel i do not trust.

[Makoben]

@tjcooper get rid of the training wheels. Looking at your video, you are already at the point where you shouldn't be using them. Next get rid of the strap. It looks like the strap is causing you to fall by keeping you from running free when the wheel cuts off. The strap saves the wheel when it cuts off. Forget that, it is easier to buy another wheel than to go to the emergency room. Just pad the wheel.

I am much younger than you(I am 67) and I embraced every time I had to run off as it got my feet moving faster and faster. I started running(stepping) off at one or two miles an hours and now I can run off at over 10. I did this by starting off road, in Florida we have this really bad grass covering white sand. This combination guarantees many runoffs and building up your run off ability. If you are twenty years old, you can run off easily, at 70, not so easily. It is really critical to find the right type of surface to start on, if you try on regular deep grass, it doesn't work. Try to find some really short grass like a soccer field, bike trail or golf greens ?. When you do ride on pavement, it will be so easy and you will have the ability to run off. Good luck

Mike

[tjcooper]

Chriull,

As I said in post, the minor cracks in payment I could just barely feel as I went over them in a sharp turn with training wheels leaning on them.  They had no affect on my balance and the wheel did not respond to them.  Must have gone over 200 cracks in the coarse of that 20 minute filming.  Besides, both "unexpected stops" were with me going straight forward and I was not even touching the "outrunner wheels" to the pavement.  That is my little game to teach me how to get good balance.

Battery:  I am a LiPo battery expert and have equipment most people do not have access to.  I can measure the internal impedence of a battery pack and its voltage, current, and power over millisecond intervals.  For my electric bike and RC airplanes, this allows be to spot batteries that are getting "weak" and either play sophisticated "rejuvenate" games or get rid of them.  I put my system on the MoHoo pack which is 16S1P (sadly I don't have connector to bring out each cell for testing and rejuvenation).  All of the tests show this is good Samsung cells 18650 with PTC circuits on each cell and they behave smoothly in discharge tests.  The thing I cannot test is if a regenerative braking happens and then you move forward again does the system have a poor time constant to switch from recharging to power output.   I have done many "rock backwards and go forwards oscillations" in my testing.  Never had a failure in any of these oscillations.  So at first blush, it seems the battery pack is working (but an intermittent PTC could easily cause the problem I am seeing and without the connector to bring out the individual cell voltage, I cannot measure this.  That is why I would like to test out another battery pack.  Best test would be 16S2P.

Makoben,

I do not understand the concept of "run off" the wheel.  Is this when you want to dismount and you just "hop off" by try to run forward to keep your balance when you hit the ground?  Believe it or not, I practiced on a soccer field on Easter with the training wheels on.  Now that is one hard and bumpy road to keep your balance but I did manage to ride for 10 minutes without falling (was hoping the crash would cushion the fall and be a safer training surface).  Don't think I will do that again.

Yes, I am loosing the training wheels this week.  Until Banggood comes back with a solution, I am just practicing "hoping up" and getting balance and slowly moving forward beside a wall with no training wheels.  Did that last night and found that I am getting much better at the "hop up".  I still need the strap to stop wheel from smashing into things beside my walkway as I practice "hop up".  I have almost 100% of case covered with foam.  But it is getting worn off quickly....may have to buy another 2 packs soon.  LOL.

    tjcooper

 

[Hunka Hunka Burning Love]

If you can find a flat soccer field with low grass, that might be a good spot to practice without training wheels on.  Or let out a little air from the tire as it's easier to get used to when the tire is softer.  Or try an empty skating rink with the side wall to help support you to get your balance.  I practiced for quite some time indoors actually.  I set up a pair of dining room chairs back to back at one end of my kitchen and another set about 8 feet away.  I would glide back and forth to get used to the balance and eventually removed one chair on each side.  It was nice to have a point A to point B to move back and forth to.  I found the learning strap to be more a hindrance to learning how to balance so I just padded my EUC up.

[Makoben]

@tjcooper What I call a run off is when the wheel stops abruptly and you are still moving. If you are quick enough, you will usually put your dominate foot out in front and try to run or walk at the speed you were just traveling. If you are successful, that is a run off, if not, it is a fall. If you have a reliable wheel and ride only on pavement, you will find you hardly ever have wheel stoppage. This means you will not develop the skill of running off the wheel with no injury. Young people tend to run more than old people and would have this skill. Remember this not "can I go out and run 5 miles an hour" but "can I stand on a treadmill that is stopped, when all of the sudden it starts at 5 miles an hour." When you are riding at 5 mph and the wheel stops suddenly, gravity will pull your body towards the earth. You only have 4 inches to go, so it takes less than a second before your foot is on the ground. The ground relative to you is moving 5 mph. If your foot is not able to move close to 5 mph, you are going to fall. Now when you train for this you cannot just say I am going to jump off and then jump off. You just planned that dismount, doesn't count. You have to train when you have no idea of when you are going to stop. Do this training by starting at slow speeds and work your way up.

I am on my second set of padding on my wheel. When the first padding starts looking really bad, strip it off and put new padding on. I pad mine 100%. You will be surprised how much better the second set of padding lasts.

Ride where you don't have to worry about hitting anyone or anything. If I see kids around, I stop and go somewhere else. Do not ride next to a body of water, too many Utube videos showing wheels and hover boards going in the water like a homesick salmon. After you learn how to ride, play nice near other people and expensive things.

Young people reading this should ignore this advice. This is a slow deliberate way to learn how to ride without injury. Young people can rely on their muscle skills, quick reflexes and speed.

Mike

 

[DS]

Cudos @Makoben, great explanation!

[US69]

On 6. April 2016 at 8:00 PM, tjcooper said:

Chriull,

As I said in post, the minor cracks in payment I could just barely feel as I went over them in a sharp turn with training wheels leaning on them.  They had no affect on my balance and the wheel did not respond to them.  Must have gone over 200 cracks in the coarse of that 20 minute filming.  Besides, both "unexpected stops" were with me going straight forward and I was not even touching the "outrunner wheels" to the pavement.  That is my little game to teach me how to get good balance.

Battery:  I am a LiPo battery expert and have equipment most people do not have access to.  I can measure the internal impedence of a battery pack and its voltage, current, and power over millisecond intervals.  For my electric bike and RC airplanes, this allows be to spot batteries that are getting "weak" and either play sophisticated "rejuvenate" games or get rid of them.  I put my system on the MoHoo pack which is 16S1P (sadly I don't have connector to bring out each cell for testing and rejuvenation).  All of the tests show this is good Samsung cells 18650 with PTC circuits on each cell and they behave smoothly in discharge tests.  The thing I cannot test is if a regenerative braking happens and then you move forward again does the system have a poor time constant to switch from recharging to power output.   I have done many "rock backwards and go forwards oscillations" in my testing.  Never had a failure in any of these oscillations.  So at first blush, it seems the battery pack is working (but an intermittent PTC could easily cause the problem I am seeing and without the connector to bring out the individual cell voltage, I cannot measure this.  That is why I would like to test out another battery pack.  Best test would be 16S2P.

Makoben,

I do not understand the concept of "run off" the wheel.  Is this when you want to dismount and you just "hop off" by try to run forward to keep your balance when you hit the ground?  Believe it or not, I practiced on a soccer field on Easter with the training wheels on.  Now that is one hard and bumpy road to keep your balance but I did manage to ride for 10 minutes without falling (was hoping the crash would cushion the fall and be a safer training surface).  Don't think I will do that again.

Yes, I am loosing the training wheels this week.  Until Banggood comes back with a solution, I am just practicing "hoping up" and getting balance and slowly moving forward beside a wall with no training wheels.  Did that last night and found that I am getting much better at the "hop up".  I still need the strap to stop wheel from smashing into things beside my walkway as I practice "hop up".  I have almost 100% of case covered with foam.  But it is getting worn off quickly....may have to buy another 2 packs soon.  LOL.

    tjcooper

 

Each cell with PTC???

thats Crap in a 16s pack!!! That is something which The Bms take care of in a pack...

throw it away:-)

 

now i understand The Cut offs....

[batteryworm]

I have an Airwheel X3. It suddenly shutdown without warning not was on 4 LED ie almost full charge. Used it about 20 times without problem but this sudden shutdown (at 5 months old) cause me to faceplant. Injured my palms and it took two months to fully recover. After this shutdown the X3 refused to charge up again.  The distributor swapped out the battery and put in a fresh one. It has been two months since and it is still working ok. But back in my mind I am always haunted by this question when will it happen again.

[Guest]

2 hours ago, batteryworm said:

I have an Airwheel X3. It suddenly shutdown without warning not was on 4 LED ie almost full charge. Used it about 20 times without problem but this sudden shutdown (at 5 months old) cause me to faceplant. Injured my palms and it took two months to fully recover. After this shutdown the X3 refused to charge up again.  The distributor swapped out the battery and put in a fresh one. It has been two months since and it is still working ok. But back in my mind I am always haunted by this question when will it happen again.

Your experience and reaction, being "always haunted by this question when will it happen again" shows in my opinion the essence of the problem with electric unicycles. Many EUC-fans ignore the risk of severe injuries. With the battery-packs becoming older we will see more accidents. It is so sad but I will sell mine. I had so much fun last summer learning and riding my unicycle. Unless the manufacturers build failsafe unicycles with redundant energy supplies it's no hobby for me, because it's not a hobby to put oneself on such a risk (see the x-rays and stiched wounds on this forum). 

[dmethvin]

6 hours ago, batteryworm said:

I have an Airwheel X3. It suddenly shutdown without warning not was on 4 LED ie almost full charge. ...  The distributor swapped out the battery and put in a fresh one. It has been two months since and it is still working ok. 

This sounds like a BMS cutout. If the distributor replaced the battery for free that's great, but of course you still have to worry that the new battery will do the same eventually. Ideally you would shunt the BMS to ensure that it did not cut out on you, there are several threads about the pros/cons here on the forum. 

[tjcooper]

KingSong69,

most 18650 batteries sold in USA have a PTC under the positive terminal in each battery.  If you take a pliers and rip off the tip, you will see a little PCB attached to tip that is like 2 mm in diameter.   The microcircuit is very small (about .8 grams) and senses voltage, current, and in most cases temperature.  If any of these go outside limits, the circuit temporarily shuts down the cell until things come back to normal operating conditions.   You can buy cells on eBay that do not have PTC, but they are rare these days.  I have a big problem with my LED headlamps in that those cells depend on the PTC not being present (and therefore about 1-2 mm shorter) than the cells with PTC.   So two cells end to end will not fit if they have PTC.   The real PTC is contained in the headlamp circuit board.   Many people on eBay and Amazon do not say if their cells have PTC present.....generally the only way you can know is by the length of a standard cell.   The PTC being present insures that you cannot over-discharge the battery.  This is really important for LiPo.  Also over-current is protected in for hard-warmers, etc.  FYI.

    tjcooper

[esaj]

39 minutes ago, tjcooper said:

KingSong69,

most 18650 batteries sold in USA have a PTC under the positive terminal in each battery.  If you take a pliers and rip off the tip, you will see a little PCB attached to tip that is like 2 mm in diameter.   The microcircuit is very small (about .8 grams) and senses voltage, current, and in most cases temperature.  If any of these go outside limits, the circuit temporarily shuts down the cell until things come back to normal operating conditions.   You can buy cells on eBay that do not have PTC, but they are rare these days.  I have a big problem with my LED headlamps in that those cells depend on the PTC not being present (and therefore about 1-2 mm shorter) than the cells with PTC.   So two cells end to end will not fit if they have PTC.   The real PTC is contained in the headlamp circuit board.   Many people on eBay and Amazon do not say if their cells have PTC present.....generally the only way you can know is by the length of a standard cell.   The PTC being present insures that you cannot over-discharge the battery.  This is really important for LiPo.  Also over-current is protected in for hard-warmers, etc.  FYI.

    tjcooper

I've understood that the PTC stands for "Pressure, Temperature, Current" (and not Positive Thermal Coefficient, like in thermistors or such), and is an entirely passive device, basically just a metal ring that's supposed to rupture or otherwise cut power in case of too high pressure/temperature/current?  Or was that the CID (Current Interruption Device)? Please correct me if I'm wrong though.

There are however separate protection circuits in some cells, that are more like mini-BMSs. I've also understood that such "protected" cells (ones with the "mini-BMS") are not good for high discharge use.

A protected battery will (hopefully) include the following protections:

1. PTC, protect against over temperature and indirectly over current and will automatic reset.
2. CID or pressure valve, will disable the cell permanently if the pressure is to high in the cell (Can be due to over charge).
3. PCB will protect against over discharge, over charge and over current, depending on design the PCB will reset automatic or when placed in a charger.

(No PCB in the above picture, just CID + PTC).

For example, in nkon.nl you can list their 18650's according to whether they have protection circuits or not, there's a whole lot more cells available without protections than with them (pretty much all the LG/Samsung/Panasonic high discharge cells are unprotected, but some companies re-pack them with protections and sell them under ther own brand name):  http://eu.nkon.nl/rechargeable/18650-size.html

EDIT: Clarification to above: I think (but don't know) that the "big-brand" "unprotected" batteries do have PTC + CID, but no PCBs.

AFAIK, the problem of using protected cells with devices like EUCs is that the protection circuit can cause a cutout, and you can't really shunt it. If you have a (decent) BMS in a multi-cell pack, you shouldn't be using protected cells (that's the job of the BMS). Still, I believe having CID (and maybe PTC) wouldn't hurt (to disable the cell if it really is about to blow).

The above is based solely on the little that I know, and I'm definitely not an expert on batteries.

[tjcooper]

esaj,

In my time at Sony dealing with the LiPoly people, they always said PTC was "Positive Temperature Correction" but no one could ever prove that it was not a carry over from Thermistor "Postive Temperature Coefficient".  But the ones I looked at under the microscope were all "active circuits" that measured voltage and amperage to be sure they were within range and would shut down the FET to disable current flow if they were outside range.  The FETs get closed where the operating conditions return to normal.   Not all the PTC that we played with had temperature compensation, but later on they all did temperature range testing.   The PCB may be a "red herring".  It was a tiny disk that carried the microprocessor/ AD converter/ FETs to do the work.  Very small circuit.

Most batteries sold for LED flashlights have the PTC since the booster circuit in the flashlight will take the battery (alkeline, LiPoly, whatever) as low as it can go to make the LEDs light up as long as possible.  Of the last 6 sets I have bought off eBay, half came with PTC (or were very long batteries) and half came with no protection (or were very short batteries).  Very few sellers of LiPo batteries on eBay say whether the PTC is present (sometimes they just say safety protected).

The CIDs I worked with were just a pressure valve.  They would let pressure out if high temperatures got it too high.   Only if there was a massive pressure surge would the CID permanently shut down the cell.  I really don't know what current 18650 cells have for CID.  I would be interested to find out if anyone can document with spec sheets what is there.

That exhausts my knowledge of PTC and CID.  I think a BMS as a separate circuit does the same work as the PTC.  Some of the BMS I have seen claim to have load balancing between the cells.  This is great if it really works.  All of my RC airplane batteries are charged on machines that have balancing devices.  It really helps protect batteries that have had 20C to 60C of burst current loading.  It is very easy to have the cells get 0.4 volt differences which can then lead to weak cells in just a few uses, and then you stand a really good chance of having the weak cell "puff up" on recharge.  For the 18650, this is where the CID is so important because the weak cell will get overcharged and tends to go to high pressure.  Hope this helps understand how the PTC, CID, and BMS all interact.

   tjcooper

[tjcooper]

esaj,

I just found this description of PTC on "battery univeristy".  It thinks it refers to Positive Temperature Coefficent, but I have heard so many other people alter the abbreviation:

Cylindrical Cell

The cylindrical cell continues to be one of the most widely used packaging styles for primary and secondary batteries. The advantages are ease of manufacture and good mechanical stability. The tubular cylinder can withstand high internal pressures without deforming.

Most lithium and nickel-based cylindrical cells include a positive thermal coefficient (PTC) switch. When exposed to excessive current, the normally conductive polymer heats up and becomes resistive, acting as short circuit protection. Once the short is removed, the PTC cools down and returns to conductive state.

Most cylindrical cells also feature a pressure relief mechanism. The most simplistic design utilizes a membrane seal that ruptures under high pressure. Leakage and dry-out may occur after the membrane breaks. Re-sealable vents with a spring-loaded valve are the preferred design. Some Li-ion cells connect the pressure relief valve to an electrical fuse that opens the cell if an unsafe pressure builds up. Figure 2 shows a cross section of a cylindrical cell.

Typical applications for the cylindrical cell are power tools, medical instruments and laptops. To allow variations within a given size, manufacturers use fractural cell length, such as half and three-quarter formats.

My attempt at getting the drawing in this copy did not work.  Just go to www.batteryuniversity.com and search for PTC and it is in the 3rd reference.

   tjcooper
 

[US69]

11 hours ago, tjcooper said:

KingSong69,

most 18650 batteries sold in USA have a PTC under the positive terminal in each battery.  If you take a pliers and rip off the tip, you will see a little PCB attached to tip that is like 2 mm in diameter.   The microcircuit is very small (about .8 grams) and senses voltage, current, and in most cases temperature.  If any of these go outside limits, the circuit temporarily shuts down the cell until things come back to normal operating conditions.   You can buy cells on eBay that do not have PTC, but they are rare these days.  I have a big problem with my LED headlamps in that those cells depend on the PTC not being present (and therefore about 1-2 mm shorter) than the cells with PTC.   So two cells end to end will not fit if they have PTC.   The real PTC is contained in the headlamp circuit board.   Many people on eBay and Amazon do not say if their cells have PTC present.....generally the only way you can know is by the length of a standard cell.   The PTC being present insures that you cannot over-discharge the battery.  This is really important for LiPo.  Also over-current is protected in for hard-warmers, etc.  FYI.

    tjcooper

What follows is just legal if "PTC" is understood as those 2mm high amperage protection on cells....i know it more under the Name "PCB"....

if not...Forget everything what follows :-)

 

I am using 18650 batteries !every day! since 3 years by my vaping Hobby...and i can say because of that i really, really have a Little more knowledge to those cells....in vaping we want the same as in EUC's: High amperage delivery, with much amperehours of use....Because of that we are using the EXACT Same batteries: Sony VTC5, LG HG2, Samsung 25R, Samsung 30Q, LG MJ1 etc etc etc

Normally you can choose, if you want an 18650 with or without protection....those without  are anything, but not rare! I see it the other way.....those with protection are the rarely used one, mostly in flashlights.....

I only use those without protection because my vape mods have all the protection needed and even a Problem if the cell is 2mm longer....

 Thats the same in an 16S1P or 16S2P block....and in our blocks the good batteries which are used are also all without protection!!!

The BMS is taking over all protections...so that you dont Need one in each cell...

In Contrary: Our packs have sometimes to deliver high amps and if a PTC protects that delivery its not that what we want!

As the Protection makes each 18650 more expensive is also a minus!

 

If you don't believe me...

Look at:

dampfakkus.de

(german for "vapingbatteries"), which is btw also the reference for all Batterie guru's here....

There is every cell listed which is used by our EUC Batterie packs....and 99% of These cells there listed are without protection and if there is one with protection it is specially mentioned....

 

 

[US69]

I think here is a real missunderstood between PCB and PTC....

PCB is a real protection (chip) 2mm wide.....for highamperage and low protection

PTC is....no real protection...just a layer which gives some protection on high temperature

[Simon Lovell]

Does anyone know how Kingsong have achieved their reputed level of extra safety in stopping? or vastly reducing? the chance of motor cut outs?

[tjcooper]

KingSong69,

can you tell me what you mean by "vaping".  In USA this is the electronic cigarettes to do electronic input of nicotine for smokers.

The PTC I am used to can support up to 10C of current discharge for a few seconds without the cell electronics forcing an 'open'.   For a 3300maH

18650, this would mean 30 amps of current for a short period of time (like 6 seconds) and then the pressure or the temperature limits would kick in and open the cell up.   But this is for high quality cells.  Some are hard pressed to do 5C repeatably.  Anyway, if my PTC protected cells can do 10C for a pack of 16 cells in serial (18650 at 3300maH), that means I can get 10*3.3 amps = 33 amps of current at 67.2 volts for a few seconds.  I think this is much higher than the average BMS would allow.   So the PTC would never come into operation in normal operation.  My best RC airplanes only get 60 amps of current at 12.8 vDC for just 6 seconds before the BEC circuit would shut them down.......and that is a lot of power to put through a 21mm diameter motor.

    tjcooper

[tjcooper]

UPDATE:  My MoHoo motherboard is really messed up.  I have been practicing on alternate days doing the "hop up" to get on petals with no training wheels.  I can now hop up almost every time and and obtain neutral balance or slight forward motion.  But after 20 minutes of practice, a new phenomenon happens.  The EUC had good gyro before I start the jump (I do the reset button every single time now, and validate that holding the unit by handle and running in forward/backward that level operation is present), but after the hop up with neutral balance, unit loses gyro within 1 second and the wheel goes out from underneath me (either forward and backward depending on how I was standing).

In the beginning I was just assuming that my jump was bad and I did not "land" right.   But I now have the landing down enough times that I know when I am properly mounted on petals.   After about 20 minutes the gyro starts dumping me on the ground.  All I have to do is get the power off button to show no lights for about 5-10 minutes and the gyro again works for another 10-20 minutes.  This is now very repeatable and I have done testing for 5 cycles to convince me that the phenomenon is repeatable.  So I think this strongly points to the motherboard.

Banggood has said they are talking with Huanxi about the problem.  Unless I get a new motherboard in the next 2 weeks, I will request a return and refund.  Since I paid for this with PayPal, I have a very powerful ally on my side.....especially with all the videos and tests I have done to show the problem.  Like Makoben said earlier,  I am now at the state of wanting to give up on EUC completely.  But a part of me really loves the technology and wants to have the fun riding them that I see in San Francisco every time I go up there.  Will let you know the final outcome.  I think I have to go to KingSong (sadly not supported in USA) or IPS or Ninebot to get something with known working technology.

What is the best price for a 14" device of these 3 vendors anyone has seen recently?  And from whom?

    tjcooper

[DS]

9 hours ago, tjcooper said:

I have been practicing on alternate days doing the "hop up" to get on petals with no training wheels.

Most probably this EUC is faulty but have on mind that you are also no experienced rider. Some riders including me reported in the early stage of learning that "shivering" sense in the legs and due loss control. It may be a good idea to find some experienced rider in your area to test your EUC, just to confirm your observations.

9 hours ago, tjcooper said:

I think I have to go to KingSong (sadly not supported in USA) or IPS

I'm surprised that you think so, have a look per example here: ewheels.com, @Jason McNeil is an active forum member.

IMHO, except you can buy personally from the KingSong factory as John Eucist did, the USA (and Australian for down there ) distributors are the best next option....we in Europe have to pay more

[US69]

On 12. April 2016 at 9:55 PM, tjcooper said:

KingSong69,

can you tell me what you mean by "vaping".  In USA this is the electronic cigarettes to do electronic input of nicotine for smokers.

The PTC I am used to can support up to 10C of current discharge for a few seconds without the cell electronics forcing an 'open'.   For a 3300maH

18650, this would mean 30 amps of current for a short period of time (like 6 seconds) and then the pressure or the temperature limits would kick in and open the cell up.   But this is for high quality cells.  Some are hard pressed to do 5C repeatably.  Anyway, if my PTC protected cells can do 10C for a pack of 16 cells in serial (18650 at 3300maH), that means I can get 10*3.3 amps = 33 amps of current at 67.2 volts for a few seconds.  I think this is much higher than the average BMS would allow.   So the PTC would never come into operation in normal operation.  My best RC airplanes only get 60 amps of current at 12.8 vDC for just 6 seconds before the BEC circuit would shut them down.......and that is a lot of power to put through a 21mm diameter motor.

    tjcooper

Yeah...

thats what i mean with vaping...

there WeAre using "mods" ...with a regulated chip inside...which is putting out Up to 200watt out of 3 Cells of 18650! It's "experienced" vaping...Not These starter Kids with a micro Batterie...

as Long As You have a Regulation by a chip like our BMS or vape mods...You don't Need a PcB...just if You Go unregulated like in a flashlight You Need The Batterie be Protect herself...

do me a favor...visit dampfakkus.de

their You can See that The high quality Cells of 18650 give out Up to 25Amps....to put a PcB in each cell of  a 16s2p pack would just Set Up The resistance of each batterie...what Nobody wants....

but better back to real Problems! Get of that Cheap Wheel and

contact Jason...and get a nice Wheel :-)

[tjcooper]

QUESTION:

if I were offered a 14" IPS from Banggood as a replacement for the MoHoo which is out of stock for a while as a free replacement, or I had to pay $500 to get a Ninebot E+, which is the better "value" deal?   The IPS has 500 watt wheel......as does the Ninebot E+.   But the Ninebot has a much bigger battery and long trip ability.  Trying to figure what I would choose.

    tjcooper

[SlowMo]

39 minutes ago, tjcooper said:

QUESTION:

if I were offered a 14" IPS from Banggood as a replacement for the MoHoo which is out of stock for a while as a free replacement, or I had to pay $500 to get a Ninebot E+, which is the better "value" deal?   The IPS has 500 watt wheel......as does the Ninebot E+.   But the Ninebot has a much bigger battery and long trip ability.  Trying to figure what I would choose.

    tjcooper

Which IPS model is it and what is the battery capacity?

[US69]

1 hour ago, tjcooper said:

QUESTION:

if I were offered a 14" IPS from Banggood as a replacement for the MoHoo which is out of stock for a while as a free replacement, or I had to pay $500 to get a Ninebot E+, which is the better "value" deal?   The IPS has 500 watt wheel......as does the Ninebot E+.   But the Ninebot has a much bigger battery and long trip ability.  Trying to figure what I would choose.

    tjcooper

Get The Ninebot and try to deal it a Little more down? :-)

sounds like the IPS Is only about 170wh? Not enough then...

[Chriull]

35 minutes ago, tjcooper said:

QUESTION:

if I were offered a 14" IPS from Banggood as a replacement

There are many different 14" IPS EUCs... I know none of them, but there are quite some reviews, posts, etc...

35 minutes ago, tjcooper said:

for the MoHoo which is out of stock for a while as a free replacement,

Seems like good fortune

35 minutes ago, tjcooper said:

or I had to pay $500 to get a Ninebot E+, which is the better "value" deal?   The IPS has 500 watt wheel......as does the Ninebot E+.   But the Ninebot has a much bigger battery and long trip ability.  Trying to figure what I would choose.

    tjcooper

I'm very satisfied with my E+. I have 556 km very steady, solid driving with it by now without any unpleasant surprises.

What i did not like with the ninebot was the speed of "just" 20 km/h - all the bikes where overtaking me driving the bike lane...;) And the "just" medium range - to my work place (13km trip, with a 100m incline as finish, weight about 90kg) the battery was quite at the end. (So i changed now to a KS16 with 828Wh;) )

There were also some cut-off/faceplant issues discussed here (as with IPS wheels, too). But imho that's an inherent issue for 500W cycles with "only" 2 cell"banks" in parallel - one can overpower such wheels. My brother managed some overleans with his E+, i never had any - depends on the riding stye (how much you ask from it)?

You have to be careful with firmware updates (also sometimes you must _not_ use it with the firmware, it was shipped with) - ninebot has a horrible history of firmware release with quite immediate motherboard bricking... The new firmware 1.3.5 seems quite stable (also timewise - ninebot seems to have stopped throwing out new version) - they just introduced some 8kHz noise with it.

When turning, the ninebot tilts a bit forward - so in tighter turns one tend to scrape first with the outward/forward tip of the pedal. Seems to be quite unique behaviour from the ninebot - but not in any way inconvinient. It also has the hardest ride mode from all unicycles (i assume so from the discussions around here) - in ride mode 0 the pedals stay absolutely straight. Just as written with turning you have a bit of a forward lean, and from time to time a small forward lean can happen. The cause of this was not exactly found - an assumption was that this happens if one drives along some specific decline/incline change patterns...

You also have the  9BMetrics logging application for iphone, if you like such stuff:

So i can't give you any recommendation for one of these two wheels, since i never had any real life experiences with an IPS, but I think that's about all i can say about the E+...