DYSFUNCTIONAL NINEBOT CRASH! --> THOUGHTS??

[Shkani04]

Hi, so after my fall today I found and joined this forum to see gather your opinions as to why my ninebot was dysfunctional  

I was riding on my ninebot for about 30 min or so hitting max speed several times. But the last instance after I hit max speed, it beeped but then quickly gave out and I had a pretty nasty fall. Usually when a person hits max speed on the ninebot, the machine pushes back on the balls of their feet and makes them slow down.This time it did not do that. I am not new to the ninebot and have been riding for about 6 months without a crash. I thought I dislocated my shoulder but thankfully everything was ok except for cuts all over.

I just do not know why this happened. Now I am hesitant to ride it again and to hit max speed.

 Any reason why this could have happened? any remedy or fix for this problem?

Thanks for you time and help, I look fwd to your replies!

H. 

[dmethvin]

Glad you weren't seriously hurt! If you look around the forum you'll see some scary stories. Wear protection.

On just about every EUC model it is possible to "over-lean" quickly or hard enough that the unit doesn't have time to do tilt-back. That is especially true if you are going uphill or if the battery is low. What model do you have and how big is the battery?

[Vik's]

Glad you are OK.

When you saying max speed - do your mean ~20 kmh (usually tiltback) or ~24-25 kmh. If you got absolute maximum speed and leaning it even more, then it is def. overlean. It could happen even at 20 kmh, depending on your weight, terrain, climbing angle and road quality etc.

What firmware *(and motherboard revision i known) your 9b1 are on?

[Shkani04]

I apologize for the double post. You can delete one them.

I understand the over lean issue but it is nothing that I haven't done before. I have been very aggressive with acceleration in the past without a problem.  That is prob why i fell so hard, I was very confident in the machine - i guess too confident. 

firmware V1.3.5 - latest one. 

Model E+

 

[Jason McNeil]

@Shkani04, what model E did this happen on? Some time back I did some limit-testing on the E, which uses the LG HE2 batteries. 

I have a theory about this sort of cut-out situation: when Ninebot designed the E, they didn't take into account normal cell degradation. In the Ninebot One, they also only use 30 cells, which gives them less safety margin ( ~60v vs. 67.2v MAX voltage) than a typical 32 cells pack in other brands. Supposing the 9B1 Engineering team did hundreds of hours of analysis & testing, setting the maximum speed with a 20-30% safety margin; then as the cells age, the internal resistance increases, with the corresponding effect of a significantly increased voltage drop as you accelerate, or try to maintain maximum speed. Ideally, all EU firmware would use some sort of aging algorithm, which would decrease the speed & make the ride of the Wheel more conservative as it ages.

If you do end up buying an upgraded battery pack, it would be interesting if you could do a post-mortem battery capacity test with something like the VC2 charger or Charge Doctor, to see what the state of the battery are in. 

[Planetpapi]

Sorry about your fall. Hope you recover soon. Like others said there could be multiple reasons for a wheel fail (It's an irony that riders find this forum AFTER the accident). Please consider giving more information as accurately as possible so members can assist you. For what ever reason it appears Ninebots have more face plants than other brands. Were you wearing ANY safety gear at the time of fall?