Inmotion V5f cut out/ turned off mid ride, major fall

[Chad Slavin]

Riding my inmotion v5f to work today, it suddenly turned itself off and I ended up in a face slide, resulting in black eye, swollen and torn lips and nose, chin is getting stitches currently, arms are cut/road rashed, glasses destroyed( bent and scratched beyond repair), jacket got torn to shreds. Anuone else ever have this issue? I have been riding it for over 6 months no problems yet, this is its first malfunction.

Edited February 18, 2019 by Chad Slavin

[Girth Brooks]

Everyone who thinks full face helmets are too heavy, scare pedestrians, or any other lame excuse for not wearing one should read this post. Best of luck in your recovery, man! That looks and sounds terrifying!

[Smoother]

@Chad Slavin that's one hell of a way to introduce yourself to the forum.  That sounds nasty and painful, and expensive.  I feel for you.

When you get some time could you fill us in on the details, as you remember them?  Crash analysis is a big thing here, which hopefully helps others not repeat the process. I cut my chin, once and only once in a face plant, but it was barely a graze, nothing like that grand canyon you are sporting. Ouch! 

Edited February 18, 2019 by Smoother

[Chad Slavin]

Ya no problem. I was having a fairly normal day on it, rode it a few miles just before the accident, running errands around town. Dropped all groceries off and was headed into work next, still had 3 out of 5  battery bars left, so 60% or so. I was riding at about 12 or 13 miles an hour, a comfortable pace without the tilt back or warning lady yelling at me to slow down. Was about to start tilting back to slow down as I arrived at work, but it turned off and I felt it roll forward, I didn't have time to put my arms out, so they were by my waist, and the face and jacket hit the pavement really hard and slid for 15 or 20 ft I feel like. About 15 people ran out to the bike lane to help me collect my unicycle and my backpack, and clean up the blood, helped me inside my workplace to clean up a bit, and took me to the medical clinic to get looked at and stitched up. Quite a day. Still love the electric unicycle, just dont know if anyone else ever had it randomly turn off on them while riding.

[Smoother]

Wow! that's frightening.  So no bumps, or dips or any other disturbance that could have produced a fatal voltage sag?  Because that is what it most sounds like.

Here's why. 

The max speed for your wheel as stated below is 15.5mph You say you were doing 12 or 13 mph so pretty much at the point where the motor torque is falling off fast.

Your battery is 320Wh (i.e small) and you were down to 60%, so even less to play with

We still don't know your weight.

Inmotion V5F

Model	V5F
Max Speed (km/h)	25
Motor	550W
Battery	320Wh
Weight	11.9kg

6 more rows

Inmotion V5F – The Wheelies

 

https://thewheelies.sg/products/inmotion-v5f

Pure speculation but I believe you were right on the edge of no available power reserve when a small power demand occurred (bump, dip, twig, rock, slight incline, you name it)  the board asked for more amps that the batteries could give, and hey presto you're sliding down the road using your chin as a brake.

 

This "theory" of mine hasn't come out of the dark.  I have long and frequently warned riders of small battery wheels to be extremely cautious when down below 60%.  Why? because as the current owner of a 340WH wheel I have experienced first hand, or should I say first face, the "joys" of pushing a small battery beyond its limits.

So, there is a sort of good news in this, assuming my theory is correct.  Your accident is 100% avoidable in the future.  All the best in your recuperation. Keep us informed of your progress.

Edited February 18, 2019 by Smoother

[pico]

Sincerely sorry to hear that. I have a V5F and this has never happened to me except when voluntarily fooling around on a very steep slope.

I would like to know the ambient temperature and your weight, please.

 

[RockyTop]

Sorry for your misfortune. I hope you heal quickly. 

I myself could not ride a wheel with less than a 1200 watt motor. They are too easy for me to over power. As @Smoother said at near top speed it does not take much to cause a shut off. 

[Chad Slavin]

It was 25°f outside, sunny, no moisture, flat level road without road blemishes. My weight is 168lbs, with my backpack make that 175 possibly

[pico]

25F is -4 deg C . At this temperature the internal resistance of the battery is way higher than say at the optimum 25 deg C.

You were riding at 60% with the equivalent of a sub 150 Wh battery. 

This is the major culprit IMHO.

Get well soon.

[s.m.]

I think low temperatures can affect this behaviour, too. 

A few days ago I started with a full battery and fresh air in the tire and wanted to take a bump very hard for testing the behaviour with more air pressure (around 3.5 bar) than my regular 2.9 bar. 

The temperature was around +5°C and I felt a "weakness" (a very soft overlean) when my wheel hit the ground and had to catch me up. Nothing bad happened but I got some unwanted adrenaline for free. 

During the summer I start requesting a power from 2 to 3kW just behind the door. During the cold I have to drive it warm, frist to avoid power related problems.

[Rehab1]

I’m sorry to hear this Chad! That is one nasty  gash! It’s wonderful that strangers came to your aid.

I use to own a V5F and absolutely trusted it. Please keep us updated. Be well!

3 hours ago, Girth Brooks said:

Everyone who thinks full face helmets are too heavy, scare pedestrians, or any other lame excuse for not wearing one should read this post. 

I fully agree! 

[Chad Slavin]

Got it stitched, jacket remnants too

Edited February 18, 2019 by Chad Slavin
More words

[IRK]

Wow. That’s awful. Get well soon. 

I wear my full face every time now just because of this kind of incident. Used to just wear a skateboard helmet but upgraded and seeing things like this makes me feel like I made the right decision 

 

My V8 has not done this. But I always feel like it is a when and not an if. At least it seems that way. 

[Chad Slavin]

I advise the full face helmet. Ill be getting one now too. Just the top of the head is not enough in this scenario...

[Planemo]

The jacket you were wearing was unfortunately worthless too. Probably worse than bare skin as the nylon can melt into a wound and be more difficult for medics to deal with than flushing out road gravel/dirt.

Get a decent motorcycle textile jacket, they are able to take huge abrasion levels and usually come fitted with armour to boot. Nowadays they can be bought to appear very casual, almost indistinguishable from a normal jacket.

And a full face lid of course!

[Planemo]

Something like this will be a good start

https://www.fc-moto.de/epages/fcm.sf/?ObjectPath=/Shops/10207048/Products/Held-Tropic-II-2016/SubProducts/Held-Tropic-II-2016-0018&Currency=GBP&Locale=en_GB&gclid=Cj0KCQiAzKnjBRDPARIsAKxfTRAv2g8kYJnS93qQKo4EqcYbFPIkJ8A0bPJfgLIjr-JAan8Gz8bZK1gaAoYVEALw_wcB

[Smoother]

6 hours ago, pico said:

25F is -4 deg C . At this temperature the internal resistance of the battery is way higher than say at the optimum 25 deg C.

You were riding at 60% with the equivalent of a sub 150 Wh battery. 

This is the major culprit IMHO.

Get well soon.

That's it exactly. I forgot to ask about the temperature. So that's also good news because now you know you wheel didn't spas out for no reason.  In addition to it being cold, and your battery low, you had also been running errands, which means the batteries had been out in the cold for a while.  If you had just left the house and rode off 40%  of that battery in say 30 minutes of straight riding, the battery probably wouldn't have got so cold; and it may never have happened. C’est la vie.

[Rama Douglas]

I too ride a V5F. Haven't had it cut off on me at speed, just a faceplant at same speed as you when I clipped a pedal on a wall beside me on a narrow sidewalk. I broke a rib on that fall. I hear a lot of riders stating that it's too small a wheel for heavier (around 180lbs+) riders. I can sympathize with that, however, I believe it's up to the rider to really feel what the motor is doing. That said, I believe it's still a good wheel for say up to 200 pound riders. I put over 1600 miles on mine and probably came close to overpowering it several times. Maybe my almost always soft, and bent knee stance kept it from doing so. I did get the full face helmet since that crash, but I've only been wearing it when I ride my XL.  Maybe I'll just switch to the full face when I ride the V5F also, to be safer...🤪

Also, what do you guys think about low speed crashes (under 15mph) vs higher speed crashes (say, over 18mph)? I'm my own experience, having had both, my slower speed crash was worse injury wise. My theory of why (among other factors, such as having a split second to prepare for the fall) is mainly about momentum. I feel like the physics behind a 12-13mph fall states that you'll just smack the ground harder than if you have momentum built up. My 22(ish) mph crash, I was able to mainly just slide on my pads, where my slower crash was just a hard smack to the pavement, with little sliding. Obviously, there are many factors, but curious to know of your thoughts... Certainly gearing up is a must, especially after bailing hard (once)...😜

And @Chad SlavinSlavin, I wish you a quick physical (and psychological) recovery...

Edited February 19, 2019 by Rama Douglas

[Girth Brooks]

@Rama Douglas I really think there's an illusion to many EUC riders that they are fine without gear at low speeds and the only ones who risk getting hurt ride fast and loose like Tishawne does in his videos. Hitting the pavement sucks at 12 or 22 miles per hour from my experience in 36 years of falling off various wheeled vehicles.

Edited February 19, 2019 by Girth Brooks

[Rama Douglas]

2 minutes ago, Girth Brooks said:

@Rama Douglas I really think there's an illusion to many EUC riders that they are fine without gear at low speeds and the only ones who risk getting hurt ride fast and loose like Tishawne does in his videos. Hitting the pavement sucks at 12 or 22 miles per hour from my experience in 36 years of falling of various wheeled vehicles.

As far as physical, my slow speed was worse, psychologically, my faster wreck was way worse. That death wobble stays with you ... 😬

[Girth Brooks]

@Rama Douglas I hit a speed bump I didn't see in my first higher speed crash. That one scared me good for sure. I remain focused on my path now. I would've been hurt good without my gear on that day. I fully realized then that the protection I ordered with my wheel was money well spent.

[pico]

27 minutes ago, Rama Douglas said:

I believe it's up to the rider to really feel what the motor is doing. That said, I believe it's still a good wheel for say up to 200 pound riders.

100% in agreement. These things talk to us, its up to us to listen.

Also got smacked really hard at 0 mph  Remember my video "The harder they fall"... Vertical head velocity can be pretty nasty...No time to fall pretty judo style....

Above 25kmh with no helmet? Not for me...

On the other hand I can hardly see myself doing tricks with full face helmet and too much padding. Want to stay as light and agile as possible.

Edited February 19, 2019 by pico
corr

[Freewheeler]

Thank you for sharing your story.

It was a stark lesson to me that the learning curve doesn't end. Once I became comfortable on my rides I had focused solely on threat assessment and practicing tighter and slower maneuvers. Now, after reading this post, I'll be placing greater importance on aspects I never really considered; learning the limits of the technology and to develop a relationship with my wheel. Oh, and I'll be getting safety gear, too!. 

I wish you a speedy and full recovery. 

 

[US69]

On 2/18/2019 at 5:00 PM, Chad Slavin said:

Ya no problem. I was having a fairly normal day on it, rode it a few miles just before the accident, running errands around town. Dropped all groceries off and was headed into work next, still had 3 out of 5  battery bars left, so 60% or so. I was riding at about 12 or 13 miles an hour, a comfortable pace without the tilt back or warning lady yelling at me to slow down. Was about to start tilting back to slow down as I arrived at work, but it turned off and I felt it roll forward, I didn't have time to put my arms out, so they were by my waist, and the face and jacket hit the pavement really hard and slid for 15 or 20 ft I feel like. About 15 people ran out to the bike lane to help me collect my unicycle and my backpack, and clean up the blood, helped me inside my workplace to clean up a bit, and took me to the medical clinic to get looked at and stitched up. Quite a day. Still love the electric unicycle, just dont know if anyone else ever had it randomly turn off on them while riding.

You where asking if that has happen to others...

so the answer is, yes , definitly. 

and the behaviour of your wheel points, for me, to a bad cell, at least one if not more!

The Im wheels have the behaviour that even if one cell drops below the minimum cell voltage, that the bms shuts down the wheel.

i have heard/seen a few of similiar reports to yours about v5/v8. As those wheels only have 2 parallel cell packs, the cells are a bit more stressed ....and so something like this can happen. i highly advise checking the battery by a pro before riding again.

yes, the low temp might have been a cause of the Situation, also,.but as you said that was just totally out of the blue, it sounds like a cell failure to me.

[Marty Backe]

On 2/17/2019 at 5:29 PM, Chad Slavin said:

Riding my inmotion v5f to work today, it suddenly turned itself off and I ended up in a face slide, resulting in black eye, swollen and torn lips and nose, chin is getting stitches currently, arms are cut/road rashed, glasses destroyed( bent and scratched beyond repair), jacket got torn to shreds. Anuone else ever have this issue? I have been riding it for over 6 months no problems yet, this is its first malfunction.

I had to remove your picture from my quoted response to you - too disturbing 

Best wishes for a fast recovery. And thanks for posting - it helps us all to keep on our toes and never forget that potential bad falls are always possible (and out-of-the-blue).

I concur with what everyone has been saying. Bad injuries can come from slow and fast riding, and I've had them both.

I do think that you better your chances against mechanical/electrical faults (what happened to you) by riding high performance wheels, even if only used at low-performance speeds.