Crashed kingsong 16B

[Isak Alexius]

Hey, i was riding home from school annd while riding i felt that the whell went unstable so i stoped and looked at the battery and it was around 30%. Then i turned it on and started accelerate when i hit around 20-25 km/h it stoped balancing me and i fell forward.  I wonder if this has happened any of you. I broke both my hand and elbow

[Seba]

2 minutes ago, Isak Alexius said:

Hey, i was riding home from school annd while riding i felt that the whell went unstable so i stoped and looked at the battery and it was around 30%. Then i turned it on and started accelerate when i hit around 20-25 km/h it stoped balancing me and i fell forward.  I wonder if this has happened any of you. I broke both my hand and elbow

What was the outside temperature at that time? Have you heard any beeps or voice messages?

[Chriull]

30 minutes ago, Isak Alexius said:

Hey, i was riding home from school annd while riding i felt that the whell went unstable so i stoped and looked at the battery and it was around 30%. Then i turned it on and started accelerate when i hit around 20-25 km/h it stoped balancing me and i fell forward.  I wonder if this has happened any of you.

At around 30% the max speed reduction sets in? Pfff... i never remember this numbers ;(

How hard did you accelerate?

A fellow rider had such an experience and wheellog data of this incident - he accelerated up to ~27 km/h too when the wheel overleaned. Since this was below 30 km/h (his beep alarm and tiltback setting) without any warning... It took him about 2 seconds to accelerate till overleaning.

At the time of the overlean (high burden) he had a battery voltage of ~59V which are about 56% charge.

 

Quote

I broke both my hand and elbow

Wish you a good and speedy recovery!

Edited November 26, 2018 by Chriull

[US69]

30 minutes ago, Isak Alexius said:

i was riding home from school annd while riding i felt that the whell went unstable so i stoped and looked

What was this "the Wheel went unstable"??? Did the pedals get wobbly and weak?

Perhaps then the caps on your Motherboard got burned or defect….and then it would be understandable that you experienced a cutout when accelerating to 20-25kmh!

Just alone the battery with 30% should not lead to a cutout. I suspect something else is the reason.

So main Question is what was this "went unstable" Situation? 

 

And btw: Good and speedy recovery!!!

[Isak Alexius]

around 10C at that time so that was not a problem i heard no beeps or voice messages. I do not remember how fast i tried to accelerate i did like i use to

[Isak Alexius]

I don't remember in what way it feels unstable just that it did, it had never happened to me before this.

[US69]

1 minute ago, Isak Alexius said:

I don't remember in what way it feels unstable just that it did, it had never happened to me before this.

My guess is that a capacitor burned….that leads to unstable driving first.....and sooner or later to a cutout, if the amp draw gets to high.

Some older motherboard versions of the KS16B had that problem sometimes….

[Chriull]

24 minutes ago, Isak Alexius said:

I don't remember in what way it feels unstable just that it did, it had never happened to me before this.

 

2 minutes ago, US69 said:

My guess is that a capacitor burned….that leads to unstable driving first.....and sooner or later to a cutout, if the amp draw gets to high.

Some older motherboard versions of the KS16B had that problem sometimes….

Once a capacitor leg is burned one has a different riding feeling - if gets much "softer/wobblier". After a capacitor leg is burned there is also always the chance that the fuse blows!

In my case (first capacitor leg burnt and then at the next higher burden the fuse blew) it looked like this:

One sees the black insulation along the one capacitor leg with some "white coating". It was not flexible anymore but hard and brittle. After removing some it looked like this:

 

[Isak Alexius]

 

 

I bought my king song 16b as used, it has driven 2000km should I continue to use it or buy a new one/get a new motherboard 

[Chriull]

 

43 minutes ago, Isak Alexius said:

so that was not a problem i heard no beeps or voice messages.

Beeps (and tiltback) occur only at the speeds one has set the alarms.

There is also a seperate overpower warning - afair this never came while riding at somewhat higher speeds but just at low speeds especially at inclines (or when the wheel stopped at some roots or stones with me dismounting...)

 

[Seba]

3 minutes ago, Chriull said:

One sees the black insulation along the one capacitor leg with some "white coating". It was not flexible anymore but hard and brittle.

It's a sign of very high current flowing from/to capacitor. Looking at this it may be a good idea to solder another cap in paralell to existing one. It will provide some redundancy and improve overall handling, but also will divide current between two caps reducing heat losses. If cap legs was so hot to burn the insulation, it could also cause the solder joint to degrade or even melt.

[Chriull]

26 minutes ago, Isak Alexius said:

 

 

I bought my king song 16b as used, it has driven 2000km should I continue to use it or buy a new one/get a new motherboard 

Open it up and check the capacitor!

Edit: One should also notice the different driving behaviour - one can not miss it.

Edit 2: And be carefull accelerating at speed above 20 km/h. The KS16B is already a stronger wheel but with it's "limited" max speed and power one can overlean it much easier than the new "high perfomance" wheels!

My first motherboard were the capacitor leg burned and the fuse blow had just "Kingsong" written on it

The replacement board i got had "Kingsong" and "V1.3" written on it:

With this V1.3 motherboard it works like charm since then (August 2016).

21 minutes ago, Seba said:

It's a sign of very high current flowing from/to capacitor.

Imo the leg of my capacitor burned on a hot summer day "pushing" the wheel up quite some inclines...

Quote

Looking at this it may be a good idea to solder another cap in paralell to existing one. It will provide some redundancy and improve overall handling, but also will divide current between two caps reducing heat losses. If cap legs was so hot to burn the insulation, it could also cause the solder joint to degrade or even melt.

Space is very limited where this capacitor sits - i tried to replace it but just got one a little bit bigger and had no chance to fit it in. Also a second capacitor beside the original one would block the airstream of the fan...

But as written above with the new motherboard everything went fine. Although i never overburdened the wheel again as much...

Edited November 26, 2018 by Chriull

[Chriull]

@Isak Alexius as small help for KS16B disassembly i just found:

 

[US69]

3 hours ago, Chriull said:

My first motherboard were the capacitor leg burned and the fuse blow had just "Kingsong" written on it

Yip, this and Versions including V1.2 where those that have a tendency to blow the capacitor.

There is even a "repair-doc" exisiting how to handle the V1.2 boards, so that the capacitor has a longer Lifetime. To shorten it: There you have to rip of the small resistor "C29" under the cap.

3 hours ago, Isak Alexius said:

 

 

I bought my king song 16b as used, it has driven 2000km should I continue to use it or buy a new one/get a new motherboard 

You should look at your board at least!!! Follow @Chriull instructions, he nailed it!

But to be honest:

Something is fishy…..you recognized a clear different behaviour = "Wheel went unstable"...then you drive on and had a cutout. Thats no coincidence!

 As KS Wheels in normal situations do not have a cutout i would highly recommend NOT to drive anymore on this Wheel, until it is clear what happend or what had become defect.

IF it is the capacitor...you should clearly recognize the different Wheel behaviour….it is like the weakest pedal Setting times 3...no hard pedals anymore.

[meepmeepmayer]

Ouch, your injuries sound bad! Did you wear wrist guards? If yes, which ones?

5 hours ago, Isak Alexius said:

I bought my king song 16b as used, it has driven 2000km should I continue to use it or buy a new one/get a new motherboard 

Most likely you just need a new board. If you felt something strange before the crash, that means the board is no longer good. Open the wheel and look at the board to see if there is something visibly wrong, probably you'll find something (but you need a new board anyways to be safe).

It will be hard to repair a wheel with a broken hand! So concentrate on healing before repairing the wheel. I hope you will heal fast and uncomplicated

[RichieV]

6 hours ago, Isak Alexius said:

Hey, i was riding home from school annd while riding i felt that the whell went unstable so i stoped and looked at the battery and it was around 30%. Then i turned it on and started accelerate when i hit around 20-25 km/h it stoped balancing me and i fell forward.  I wonder if this has happened any of you. I broke both my hand and elbow

Were you wearing hand/wrist protectors or elbow guards or were you unprotected in those areas?  If not, do you think they would have prevented the breaks?  If you were wearing protection, I hate to think how bad things would have been if you weren't!

[Pete Bucknell]

This is a year later than your first post, but I recently face planted on my Kingsong 16B after about 3800km of no incident.

The wheel hit an uneven tile in the path, a bit sunken. doing about 20km/h I estimate.

I'm not sure if I was thrown down by the bump, or the wheel cut out when it hit the bump. Any ideas guys?

After getting back up I got back on the wheel and it cut out immediately at 5km/h   and I bit the dust again. Now it won't turn on.

I'm taking it in to repair shop tomorrow.