Warning on Riding EUC in a Seated Position

[Roll_On]

When my KS-18S power cut out so sudden, and I was riding in a seated position, I just cash into the pavement so sudden like any other face plant except there is not enough body to distribute the impact force, and my left arm was badly injured.  I do not recommend ever riding seated for even normal speed.  Here is my story:

On a clear good weather day I was commuting home (3.5 miles one way) riding seated on KS-18S (only used 8 months never with an issue). My usual commuting speed is about 10 MPH or less.  About half mile to home, the KS-18S power cut out (with no prior warning of any electronic issue and battery at 90%), and I crashed into the pavement so fast I was immediately in massive pain.  My left arm just happen to be closer to the pavement, and took all the  damage. The ulna bone dislocated, and the radius bone fractured (such severe pain). Helmet protected my head and face, and no injury to the leg or the body.

The specialist doctor knew something about the EUC (kind of surprise), and he explained that there was no other part of the body to distribute the impact force, and that is why the left arm took all the impact force.  Since the arm bone is much smaller than the leg bone, fracture is the expected result.  If I was riding standing, and falling, the leg and the body with more body mass would absorb the impact much more.

For the past 8 months, I have only been riding in standing position so that auto driver could see me better with the flashing red light on the helmet.  It was only because I was so close to home that I decided to ride seated, and the power cutoff happen.  Before KS-18S I have rode the Inmotion V8 (no seat) for 2 years.

[.....]

Sorry to hear that and thanks for the share. Yeah, I wondered how much worse a seated accident would be. What speed were you traveling at cutout? Making me reevaluate if i should bother trying to learn seated riding  at all. How long did the doc give you for recovery? Again, my condolences as that totally sucks.

[Roll_On]

My usual commute speed is around 10 MPH due to traffic lights on the street.

The recovery is about 6 weeks to 8 weeks depending on your age and physical fitness.  I am physically fit but I am pass age 60.

Learning something new is always good.  I have always thought that a seat EUC could be a great utility vehicle should you hurt your leg such as ski accident.  So, a seated EUC can help you get around easily on slow speed just like a electric handicap chair.

[Kens]

Any other protective equipment beside your helmet? Also full face helmet?

[Chriull]

3 hours ago, Roll_On said:

and my left arm was badly injured

Sorry to hear - hope you recover fine!

3 hours ago, Roll_On said:

I have only been riding in standing position so that auto driver could see me better with the flashing red light on the helmet.

Like this

?

Sorry - i immediately got this picture in mind reading your line and could not resist sharing it! 

 

[Rehab1]

Best wishes on a speedy recovery @Roll_On! 

[WI_Hedgehog]

I am sorry to hear of your accident. Thank you for sharing, the flashing light is something I've been thinking about, and would not have thought to put it on the helmet.

i hope your recovery is quick and complete. 

Edited April 17, 2020 by WI_Hedgehog

[ABS Knut]

What do you think caused the cutout, just random or was it due to sitting? I know many people including myself who ride sitting at faster speeds.

[nickysneids]

4 hours ago, ABS Knut said:

What do you think caused the cutout, just random or was it due to sitting? I know many people including myself who ride sitting at faster speeds.

Yeah that's wild.. a cut out at 10mph? Something must be wrong with that wheel internally or there's no reason why a cut out should have occurred.

Feel better though! Wish you a speedy recovery.

[someguy152]

are you sure there were no battery problems. does the battery charge fully? i have an 18S as well and it is not charging fully, and this makes me more paranoid

[Chriull]

11 minutes ago, someguy152 said:

i have an 18S as well and it is not charging fully, and this makes me more paranoid

Paranoid is maybe overreacting, but beeing (very) worried would be ok!

Best to replace/repair charger/batteries!

[Roll_On]

Thanks for the get well message.  To answer a few of the questions asked:

Any other protective equipment beside your helmet?  After more than 2 years of commute riding experience, I stop wearing knee padding, and arm padding especially at low commute speed.  While riding in standing position, I have encountered a bad wide crack in the road, and was able to jump off without injury.  Now it makes senses that you cannot do evasive movement while seated on the EUC.

What do you think caused the cutout, just random or was it due to sitting?  Sitting is not the issue.  I am 170 lb.  I have open the KS-18S to change flat tire after learning to ride sitting down for.  I did not notice any structure issue with the plastic.  The weather is not hot in the S.F. Bay Area, and I have not notice any heat build up.  After the power cutout, the KS-18S could not be switched on.  BTW, I have yet to ship the KS-18S back to Jason of eWheel due to lack of a good left arm.  KS-18S is heavy and bulky once packed, and two hand is needed to bring the large package to FedEx for shipment.  Soon I will ship it back to eWheel, and I will report the problem diagnose by eWheel.

Are you sure there were no battery problems. does the battery charge fully?  KS-18S was 8 month old, and never any battery issue. At the start of commuting home, the battery was at 90% of full charge.  I suspect it was a chip on the circuit board.  We will see what the diagnose by eWhee.

[Darrell Wesh]

On 4/17/2020 at 8:03 PM, Roll_On said:

Thanks for the get well message.  To answer a few of the questions asked:

Any other protective equipment beside your helmet?  After more than 2 years of commute riding experience, I stop wearing knee padding, and arm padding especially at low commute speed.  While riding in standing position, I have encountered a bad wide crack in the road, and was able to jump off without injury.  Now it makes senses that you cannot do evasive movement while seated on the EUC.

What do you think caused the cutout, just random or was it due to sitting?  Sitting is not the issue.  I am 170 lb.  I have open the KS-18S to change flat tire after learning to ride sitting down for.  I did not notice any structure issue with the plastic.  The weather is not hot in the S.F. Bay Area, and I have not notice any heat build up.  After the power cutout, the KS-18S could not be switched on.  BTW, I have yet to ship the KS-18S back to Jason of eWheel due to lack of a good left arm.  KS-18S is heavy and bulky once packed, and two hand is needed to bring the large package to FedEx for shipment.  Soon I will ship it back to eWheel, and I will report the problem diagnose by eWheel.

Are you sure there were no battery problems. does the battery charge fully?  KS-18S was 8 month old, and never any battery issue. At the start of commuting home, the battery was at 90% of full charge.  I suspect it was a chip on the circuit board.  We will see what the diagnose by eWhee.

You need to open the wheel up and check the motor wire. For some reason my 18s motor wire became disconnected while my friend was riding it at low speed and it cut out on him. He was completely fine at that slow speed but it did not turn on after it cut out. 
when we opened it up the motor wire had just disconnected and we had to buy a new connector and solder it back together.

That is most likely what happened to you. And thankfully an easy fix. After you solder it back you should have no paranoia about riding seated again. The 18s is a relatively trouble free wheel with hardly any controller issues. 

Edited April 19, 2020 by Darrell Wesh

[Roll_On]

Thanks Darrell for mentioning that your KS-18s motor cutout was due to wire disconnection.  I will have my final left arm surgery to remove the pins on Mon 4/20. Soon after that I will open it up and check on the wire, and report back.

Side topic, Darrell was your friend riding KS-18S standing or seated when the cutoff happen?

Once my left arm / wrist has regain all the motion, I do plan to ride the KS-18S for commute, and in standing position for continue safety, (a) Car drive can see me better, (b) Able to see a bit further out for road condition, and (c) Evasive jumping off the wheel when needed.

[Darrell Wesh]

1 hour ago, Roll_On said:

Thanks Darrell for mentioning that your KS-18s motor cutout was due to wire disconnection.  I will have my final left arm surgery to remove the pins on Mon 4/20. Soon after that I will open it up and check on the wire, and report back.

Side topic, Darrell was your friend riding KS-18S standing or seated when the cutoff happen?

Once my left arm / wrist has regain all the motion, I do plan to ride the KS-18S for commute, and in standing position for continue safety, (a) Car drive can see me better, (b) Able to see a bit further out for road condition, and (c) Evasive jumping off the wheel when needed.

Standing. Weird that you sustained those injuries though most people say your knees take all the impact in a seated cutout and you have less of a distance to fall so the fall is less severe.

[FreeRide]

58 minutes ago, Darrell Wesh said:

.... most people say your knees take all the impact in a seated cutout ....

I've not seen many actual reports, I think it is more correct to say people were speculating about the most likely injuries if crashing in the seated position.  Not to mention each accident can be quite different, root cause and many other factors can make a big difference. 

[Darrell Wesh]

3 hours ago, FreeRide said:

I've not seen many actual reports, I think it is more correct to say people were speculating about the most likely injuries if crashing in the seated position.  Not to mention each accident can be quite different, root cause and many other factors can make a big difference. 

Well I know two people who have cutout while seated and told me knees took everything and it was no big deal with knee pads on 

[MetricUSA]

Wow, sorry to hear that, but seated or standing got to be extra careful with an unicycle... Wonder why it cut out??? I have not experienced that except that I keep a strap on an accidentally pulled on it...like a kill switch...

Funny you would show that, Chriull... because I now use arm blinkers so people from my side will see me now!!! 

https://www.instructables.com/id/How-To-Make-a-Bike-Blinkers-Into-an-ArmBody-Blinke/

[nickysneids]

16 minutes ago, MetricUSA said:

Wow, sorry to hear that, but seated or standing got to be extra careful with an unicycle... Wonder why it cut out??? I have not experienced that except that I keep a strap on an accidentally pulled on it...like a kill switch...

Funny you would show that, Chriull... because I now use arm blinkers so people from my side will see me now!!! 

https://www.instructables.com/id/How-To-Make-a-Bike-Blinkers-Into-an-ArmBody-Blinke/

What kind of strap on do you prefer?

[MetricUSA]

My airwheel Q3, first euc, and in profile pic, came with one...see it??? I LIGHTLY hold on to it...

Edited April 21, 2020 by MetricUSA

[nickysneids]

Just now, MetricUSA said:

My airwheel Q3, first euc, and in profile pic, came with one...see it???

Ah yeah haha I was just playin around, a "strap on" could also be consider a sex toy.

[MetricUSA]

OH then you have to ask my girlfriend....

[Sugarat]

I do wish the manufacturers would put some investment into making the wheels more reliable.  For example, if battery voltage drops, some big capacitors somewhere could take the load for a few seconds and sound an alarm..   There must be a way they can protect against cut outs, even if it means a small amount of extra cost, it would be worth it. I for one would buy a wheel with extra safety features!!

[Roll_On]

Hi Everyone:  My left arm was much better, and today Sat 5/02/2020 I open up the KS-18S to see if there was a simple reason for the power cutout.  The fuse was blow quite badly.  One of the fuse leg was blow totally away, probable due to a big electrical spike. The fuse receptacle of one leg was damaged as well.  The fuse still remain with one leg in the fuse socket.  See photo.  I manage to adjust the receptacle to allow insertion of a replacement fuse.  I added a tiny solder dip to insure a firm hold of the fuse.  I send photo to eWheel.  Hope there is an explanation why the huge electrical spike.  Now, the KS-18S is back to normal, and I am riding in the neighborhood in standing position.  I should be commuting to work shortly.  I learn my lesson, and I will NOT be riding seated with speed greater than 5 MPH.

https://drive.google.com/file/d/1UfjroalAnCCWyFYi5QSglIJkQk1hzjNw/view?usp=sharing

 

The unpredictability of fuse blown leading to power cutout is quite scary.

Reply to Darrell Wesh's comment:  "most people say your knees take all the impact in a seated cutout and you have less of a distance to fall so the fall is less severe."   When the auto balance is gone due to power cut out, your body falls forward so fast with so much force, the head/helmet would hit the pavement if not for the hand that was bought to the front of the head. 

The EUC seat is 28" from the ground.  My body seated measure 36" from the seat to the top of head/helmet.  Once the EUC loose its balance, and starts to fall forward, the bulk of my weight 170 lb. times the speed about 10 MPH is thrown forward onto the ground.  There is lot of impact force which explain why my left arm bone fractured and dislocated.  My knee only have a small scratch without knee pad.  If I was standing, and falling, the body, the stronger leg bone will help to absorb a lot more impact force.

 

Edited May 3, 2020 by Roll_On
Add photo link to google drive

[WI_Hedgehog]

Sad to hear of your crash. 

It sounds like a bad connection that resulted in heating and an ongoing electrical arc over time, eventually resulting in burning up the connector and circuit failure.

I've seen great riders run away from a crash, but all were standing. You shed insight on the risks of sitting.