KS 14s cutout!

[Shad0z]

so i was in a group ride, i was riding next to a newer  rider who a few weeks ago got his ks14s 850wh

and we were riding slowly and carefully with a few other riders.

and towards end of the day he still had about 50 percent battery

and we decided to ride a little down the road at moderate speed.

and his wheel simply, cut out and he faceplanted and his hands were bleeding he hit his head and the wheel rolled to the side

 

i helped him but he was hurting so we checked the wheel... everything fine and 50 percent battery and it cut out at about 25 kph (he is 90 kg) but he was still riding carefully

he had tiltback set to 30 kph and alarms to 27, and there was no beeps, at all and it was on a straight even road

 

an unfortunate accident. does anyone have a good explanation for this? or what happened? 

[US69]

25 minutes ago, Shad0z said:

so i was in a group ride, i was riding next to a newer  rider who a few weeks ago got his ks14s 850wh

and we were riding slowly and carefully with a few other riders.

and towards end of the day he still had about 50 percent battery

and we decided to ride a little down the road at moderate speed.

and his wheel simply, cut out and he faceplanted and his hands were bleeding he hit his head and the wheel rolled to the side

 

i helped him but he was hurting so we checked the wheel... everything fine and 50 percent battery and it cut out at about 25 kph (he is 90 kg) but he was still riding carefully

he had tiltback set to 30 kph and alarms to 27, and there was no beeps, at all and it was on a straight even road

 

an unfortunate accident. does anyone have a good explanation for this? or what happened? 

I personally wouldn' t ride it again...

Something is defect...battery perhaps, or something on the board. Hard to say. Needs to be open, battery has to be checked, board too.

[Shad0z]

21 minutes ago, US69 said:

I personally wouldn' t ride it again...

Something is defect...battery perhaps, or something on the board. Hard to say. Needs to be open, battery has to be checked, board too.

it worked fine after the accident. my freind is thinking of returning it and buying ks16s instead 

[US69]

3 minutes ago, Shad0z said:

it worked fine after the accident. my freind is thinking of returning it and buying ks16s instead 

It "might" work fine...but really , actual KS don't do that on a regular Basis, just cutting out of the blue. If some cells are defect, they might work "sometime" and on the slightest rise of amperage draw you might get the next cutout. Or if just some caps or resistor is loose and shortening from time to time.

BTW: This goes for every wheel.....you receive a cutout or whatever "unnormal" behaviour? Check the wheel. It is not meant to do that and certainly will not repair from "itself"...

[meepmeepmayer]

3 hours ago, US69 said:

BTW: This goes for every wheel.....you receive a cutout or whatever "unnormal" behaviour? Check the wheel. It is not meant to do that and certainly will not repair from "itself"...

Yep! Never ride a wheel that had any unexpected or unresolved strange behavior or failure.

If he really wants a 16S, at least this is the perfect excuse for a return.

[Shad0z]

1 hour ago, meepmeepmayer said:

Yep! Never ride a wheel that had any unexpected or unresolved strange behavior or failure.

If he really wants a 16S, at least this is the perfect excuse for a return.

he is even considiring a used ks18s, because he knows he is going to need that power. im agreeing with him. I tried his ks14s and a 16s the same day

going from my gotway tesla the ks14 felt like rolling on a rubber ball. The riding mode was very "bouncy" even on expert mode. And it didnt feel like it could take much of a bump before quitting

the ks16s. Also very bouncy. But bouncy is a good way and a little bump up in power

But still too soft for my liking

so i think he should return it and get a ks16s. 

 

[US69]

3 hours ago, Shad0z said:

he is even considiring a used ks18s, because he knows he is going to need that power. im agreeing with him. I tried his ks14s and a 16s the same day

going from my gotway tesla the ks14 felt like rolling on a rubber ball. The riding mode was very "bouncy" even on expert mode. And it didnt feel like it could take much of a bump before quitting

the ks16s. Also very bouncy. But bouncy is a good way and a little bump up in power

But still too soft for my liking

so i think he should return it and get a ks16s. 

 

Just for fun...

you started with THE MOST hardest pedal setting ever with the Tesla :-) just recently released. And good for you :-)

i would say that the S Series follow on as  the next hardest ....

if you ever want to try something wkth a REAL bouncy/weak pedal setting....try a IPS lhotz :-)

you will think how the hell did people ever ride on this :-)

[DaveThomasPilot]

I wonder if the battery was really 50% full.

Several 14C control boards (e.g. mine) have had very inaccurate voltage readings (as reported by an app).  When their notion of the battery voltage is too high, the control board will think the battery is overcharged after a full charge.  This makes the wheel unrideable until the battery is discharged, due to the tiltback mechansim.

So, if the control board thinks the battery voltage is higher than it really is, the throttling mechanisms that would normally occur when the battery voltage gets low won't work.  

Can you measure the actual battery voltage?

I'd really like to get the details on the root cause of the control board voltage measurement inaccuracy.  I recall a thread where a KS person said it was "component stress", but some more detail would be helpful.  Especially like, what caused the stress, being on the charger too long?  Fast charging (maybe balancing circuit can't handle the current)?  Are all KS wheels susceptible?

[Cloud]

Did you accelerate right before the cutout? Was the pavement smooth or any irregularities? Have the beeps and tiltback been tested to be operating properly otherwise?

[US69]

@DaveThomasPilot we r talking about the 14s ....not 14c... and these are not Suspicious to wrong voltage readings.

also a wrong voltage reading alone can not be the culprit for a real cutout.  but as said....further testing needs to be done

[Shad0z]

9 hours ago, Cloud said:

Did you accelerate right before the cutout? Was the pavement smooth or any irregularities? Have the beeps and tiltback been tested to be operating properly otherwise?

The pavement was actually very smooth no incline. just flat and he accelerated slightly but it was a pretty slow acceleration 

[Shad0z]

14 hours ago, US69 said:

Just for fun...

you started with THE MOST hardest pedal setting ever with the Tesla :-) just recently released. And good for you :-)

i would say that the S Series follow on as  the next hardest ....

if you ever want to try something wkth a REAL bouncy/weak pedal setting....try a IPS lhotz :-)

you will think how the hell did people ever ride on this :-)

i dont want to imagine

i did try a ks18s for a few kilometers

it was hard compared to the other ks models. But it still had that slight bounce to it. But of course not to forget. The huge design you can sit on

not a bad wheel.. Maybe a little too tall. But im lovin the ultra hard mode with the tesla (even though i use soft mode) 

but kingsong wheels are fine i think Until you hit the tiltback by accident ._. (i tried it on the ks16S) it does give you a punch if you dont see it coming  

so im assuming that it is not much different on the ks18s

im not shifting to ks for reasons.. Yet

well for now im happy with what i bought

[DaveThomasPilot]

 

Quote

we r talking about the 14s ....not 14c.

I realize that...

 

Quote

.. and these are not Suspicious to wrong voltage readings

 Really?  Why do you say that?  That's what I'd like to confirm.

Marty Bache had to replace his control board on a 14s (or maybe it was a 16s) after being on charger for a long time.  It was doing the tilt-back thing.  That's what got me worrying the (design?) issue still isn't resolved.

[DaveThomasPilot]

Also, if the battery voltage is too low to provide enough torque/speed you'll faceplant.  Is that really distinguishable from a "cutout"

[Shad0z]

21 minutes ago, DaveThomasPilot said:

Also, if the battery voltage is too low to provide enough torque/speed you'll faceplant.  Is that really distinguishable from a "cutout"

he wasnt going that fast

[Cloud]

50 minutes ago, DaveThomasPilot said:

Also, if the battery voltage is too low to provide enough torque/speed you'll faceplant.  Is that really distinguishable from a "cutout"

It happened on earlier models / firmware ( including my own face planting experience at least twice) but then kingsong introduced pretty conservative speed warnings/ tiltback to avoid this situation . He says there were no beeps or tiltback

[US69]

48 minutes ago, DaveThomasPilot said:

Also, if the battery voltage is too low to provide enough torque/speed you'll faceplant.  Is that really distinguishable from a "cutout"

Maybe if you try  on a 0-10% battery you can get the BMS to cutoff because of low voltage protection.

KS predicts 0% battery at about 52-53 Volt. The low voltage protection from the BMS only jumps in at about 48V. Beside the fact that on:

Quote: "carefully and slowly riding" you are not able to have such a big voltage drop.

And then there are -like Chriull said -the conservative Speedwarnings and tiltback, which dont allow you to push your wheel o fast or to hefty on a low battery.

[DaveThomasPilot]

dont allow you to push your wheel o fast or to hefty on a low battery.

But, that all depends on the control board knowing the battery voltage is low.  If it reads high, regardless of actual battery voltage, no tiltback or conservative tiltback will occur.

And, it will happen at any speed, if the actual battery voltage is low enough.

[Shad0z]

i wrote to him.. he seems pretty shoock after only having a wheel for a month, his jeans got damaged, his hand was injured he hit his knee and his expensive glasses were broken,

he doesnt seem to happy with a euc after this, he is convinced it happoened out of nowhere. but to be honest he was pushing it at 40-50% and he weighs about 100kg with his stuff

to be honest im not suprised that a 100kg guy cut out on a 800W 14 inch wheel at 50%...

now im just trying to make him give euc a second shot ?

[kasenutty]

So, what's your friend's name?

[mezzanine]

I'm convinced that people underestimate the psychological effect of having a crash.  A big reason to be careful if you want to keep using your EUC is the unpredictability of one's psychological reaction to a spill.  

[Shad0z]

1 hour ago, kasenutty said:

So, what's your friend's name?

Hmmm...why? ?

[kasenutty]

Was it George Glass? 

[Shad0z]

1 hour ago, mezzanine said:

I'm convinced that people underestimate the psychological effect of having a crash.  A big reason to be careful if you want to keep using your EUC is the unpredictability of one's psychological reaction to a spill.  

 guess im one of the lucky ones. I tumbled around badly. i was feelinf adrenaline. But then i git on my wheel and drove home for some bandages

but my freind needed to sit for About 5 minutes :/ 

i just think its bad that a spill made him think if not getting any euc. Especially when he is 100% convinced that it cutoff randomly for no reason. Not the low power motor, not any bad algorithms. Nothing. He is just convinced it cut out for ni reason and it will happen to any other euc..

everything has a reason...

 

 

4 minutes ago, kasenutty said:

Was it George Glass? 

No why??

[mrelwood]

In my understanding the 14S is quite an adept wheel, so overleaning one would definitely be distinguishable from an out-of-the-blue cutout. "Only" 800W on level pavement is definitely enough for easy cruising.

Sorry to hear about the fall.