What speed is safe to ride?

[Jon Stern]

13 hours ago, Rehab1 said:

Recent video posted on a NB forum. It depicts some idea of what excessive speed can cause. I pray he is ok.

I'm trying to work out what caused the accident. He loses it just as he reaches the painted arrow. I'm wondering if he was trying to dodge around it (in some countries road making are painted in very thick paint, creating a slight bump in the road). I don't see any potholes, or signs of a speed wobble.

Anyone got any ideas?

[Mono]

On 11/17/2018 at 2:18 AM, Jon Stern said:

I'm trying to work out what caused the accident. He loses it just as he reaches the painted arrow. I'm wondering if he was trying to dodge around it (in some countries road making are painted in very thick paint, creating a slight bump in the road). I don't see any potholes, or signs of a speed wobble.

Anyone got any ideas?

Running out of torque due to overspeed. Are you aware that the torque of the motor decreases with increasing speed whereas the necessary torque to keep the speed up increases? That means that the "access torque" available for self-balancing (EDIT: in particular for any acceleration, not for deceleration) decreases quite rapidly with increasing speed.

[Chriull]

2 hours ago, Mono said:

That means that the "access torque" available for self-balancing decreases quite rapidly with increasing speed.

Just as "clarification" - this sentence  implies a sudden stop of support by the  wheel. Once one hits the torque over speed limit the difference of needed torque and max available for this speed sends one down to earth. Hitting this limit fast enough (some pothole, thick painting, incline or just accelerating) can easily make this feel like a cut off.

[Electroman]

12 hours ago, Mmhmmm said:

When most experienced people see someone doing something dangerous without proper safety gear and precautions, don' t they think to themselves, "bad idea!"? Why people think it is cooler to not wear gear is hard to understand. Professionals and experts in any field learn the best methods and then become very proficient in their application. Having the very best safety gear for any situation is a mark of intelligence. In actual use, it takes less time to put on and take off gear as you get better at using it. Any injury will take up more time and money than what is spent on gear. My motto is All The Gear, All The Time; ATGATT. It should be a personal badge of honor to not take short-cuts with safety and also to ride carefully, attentively, and without being incorrectly over-confident. Each of us has the opportunity to be a good example to others and to promote a positive opinion of our sport for the general public.

Yup, some words of wisdom.

Agree with all of it ,well to be honest I am most certainly not always riding carefully quite the opposite, I might even be pushing the luck at times but try to stay within my skill set. The important part the way I see it is at least I am respectful to others in traffic which is more than I can say for some others I have seen, I see small children I almost crawl to a halt and make sure the parent(s) can be aware of me as well as react with the children before overtaking, yes it take s a lot of time every now and then with lots of people outside but I will never run down a child if I can prevent it, nor any other human being or even animal.

This to me is the very first priority and also try not create havoc in traffic and to create situations after I have passed, if I ride like a lunatic after that it is in my best interest not to take the pain of a crash, self preservation. But this is also a great hobby and I openly admit I am a speed demon, I enjoy it where as others enjoy a slow cruse in nature, some of which I sometimes see in videos overtake people, cars etc in a way I would never do myself and absolutely not call a safe, respectful overtaking. Even more comical if called out on going fast myself where I endanger nobody else but myself, if I crash going like that I had it coming but innocent fellow humans around me certainly did not ask for it so that's my take on it at least. Obviously if I had kids at home to feed I would likely also take even fewer risks due to the responsibility, anyways this is my personal take on it and get a lot of positive smiles when out respecting others in traffic like that, but they do not see me later pushing it, thankfully.

Perhaps it is possible many do not wear for ex a helmet out of pure convenience rather than trying to look cool though, although likely all kind of reasons exist including to look cool, not mess up the hair or other silly explanation to not wear one? I am however speculating so..? I started out not wearing a helmet learning, once I had it I got one, not wrist protection however, learned the hard way and yes, I hope others can learn from that too.

[Mono]

1 hour ago, Chriull said:

Just as "clarification" - this sentence  implies a sudden stop of support by the  wheel. Once one hits the torque over speed limit the difference of needed torque and max available for this speed sends one down to earth. Hitting this limit fast enough (some pothole, thick painting, incline or just accelerating) can easily make this feel like a cut off.

Right, referring to the self-balancing as I did is somewhat misleading. What happens is that the pedals cannot anymore resist the down pressure (the same pressure they could resist with a little lower speed just before). The pedals will just give in and the wheel will nose dip. This lack of torque is only for forward torque, not for braking. Also for this reason, exceeding the limit torque is potentially savable, while the motor going into idle (zero torque in any direction for the rest of the ride) or shutting off is not savable from any practical perspective.

[Electroman]

14 hours ago, Mono said:

Right, referring to the self-balancing as I did is somewhat misleading. What happens is that the pedals cannot anymore resist the down pressure (the same pressure they could resist with a little lower speed just before). The pedals will just give in and the wheel will nose dip. This lack of torque is only for forward torque, not for braking. Also for this reason, exceeding the limit torque is potentially savable, while the motor going into idle (zero torque in any direction for the rest of the ride) or shutting off is not savable from any practical perspective.

Very fitting, my golly I think that is exactly what happen to me some 10-15h ago?

Had a bit extra weight on me in the backpack, lower temperature that I am use to ride the MSX in etc cause while accelerating to 58.2km/h according to the app I had the 80% warning and immediately a dip forward of the peddles of about 1/3", 1 cm or whatever just approximately?

I ride very aggressively a lot of the time but perhaps even more so today and used to head that warning, I reacted very fast and let go of forward pressure, even slight deceleration to get outside warning range but I am thinking now it might just have saved me from something nasty?

 

[Chriull]

4 hours ago, Electroman said:

Very fitting, my golly I think that is exactly what happen to me some 10-15h ago?

Had a bit extra weight on me in the backpack, lower temperature that I am use to ride the MSX in etc cause while accelerating to 58.2km/h according to the app I had the 80% warning and immediately a dip forward of the peddles of about 1/3", 1 cm or whatever just approximately?

I ride very aggressively a lot of the time but perhaps even more so today and used to head that warning, I reacted very fast and let go of forward pressure, even slight deceleration to get outside warning range but I am thinking now it might just have saved me from something nasty?

 

Seems so. I "simplified" the one graph i made with the wheellog data of an overlean of an KS 16 C: (from https://forum.electricunicycle.org/topic/7855-anatomy-of-an-overlean/?tab=comments#comment-107721

 

It shows the motor current (== torque) over speed (green line with arrows showing the "time flow") and the max torque over speed limit (blue lines for different battery voltages). With lower temperatures these lines will get "lower" (shift left and down ?as the internal resistance of the battery pack increases?), so one reaches the limit earlier.

If there is no reaction from the rider once one reaches the limit, one sees here nicely how the torque (current) goes down along the limit line - and the "missing torque" sending the driver flying...

If one, like you described, immedeately reacts and breaks/let go the forward pressure once one reaches the limit just "nothing" happens - one stays well inside the limit. One just had the sensation of the pedal dipping and maybe got some adrenaline rush

[Mono]

54 minutes ago, Chriull said:

If one, like you described, immedeately reacts and breaks/let go the forward pressure once one reaches the limit just "nothing" happens - one stays well inside the limit. One just had the sensation of the pedal dipping and maybe got some adrenaline rush

And getting back to the original question: when this happens it is safe to say that the speed was way beyond safe speed.

5 hours ago, Electroman said:

while accelerating to 58.2km/h according to the app I had the 80% warning and immediately a dip forward of the peddles of about 1/3", 1 cm or whatever just approximately?

It could also be that the controller software is reacting by going into super soft mode when you pass above, say, 90% load. In any case, this is a situation you really want to avoid unless you enjoy the idea to spend a month or two in a hospital bed.

[Electroman]

2 hours ago, Chriull said:

Seems so. I "simplified" the one graph i made with the wheellog data of an overlean of an KS 16 C: (from https://forum.electricunicycle.org/topic/7855-anatomy-of-an-overlean/?tab=comments#comment-107721

 

It shows the motor current (== torque) over speed (green line with arrows showing the "time flow") and the max torque over speed limit (blue lines for different battery voltages). With lower temperatures these lines will get "lower" (shift left and down ?as the internal resistance of the battery pack increases?), so one reaches the limit earlier.

If there is no reaction from the rider once one reaches the limit, one sees here nicely how the torque (current) goes down along the limit line - and the "missing torque" sending the driver flying...

If one, like you described, immedeately reacts and breaks/let go the forward pressure once one reaches the limit just "nothing" happens - one stays well inside the limit. One just had the sensation of the pedal dipping and maybe got some adrenaline rush

Thanks a lot Chriull, appreciate the information and indeed it seams to match up very well with your description, even down to the feeling of the peddle when giving in a bit. Not like total free fall 1cm or so, ohh no there was some electromagnetic resistance there alright just nowhere close to enough to keep the full peddle up right to calibrated level.

So stupid of me not to log in Wheellog, but I know how it felt so to speak and through the years I have to learn to think and even analyze real fast staying calm enough even under pretty chaotic situations. Might be smart to be more technical about it understand exactly what is going on cause the brain is like it it is and crave speed, but as soon as accepting there is no more to be delivered after a certain point and that point is not fixed, well maybe it will help to try to still stay within that line just with a bit more buffer zone?

I really cannot wait til the day someone solve this inherent "technical limitation" of our wheels, I absolutely do not like the limiting factor of the other brands and call it safety (and it is I suppose) I still do not like it and likely never will in that form. It is safer, probably, is it better, perhaps it may well be a lot of things but to me it is limiting and to me this is a fast action sport, a stress reliever and resetting me after a hard days work, re energizing my own batteries.

Yes a bit of adrenaline rush will come knock, even when being in many similar situations it's just the human condition hehe

1 hour ago, Mono said:

And getting back to the original question: when this happens it is safe to say that the speed was way beyond safe speed.

It could also be that the controller software is reacting by going into super soft mode when you pass above, say, 90% load. In any case, this is a situation you really want to avoid unless you enjoy the idea to spend a month or two in a hospital bed.

I know it's dumb to go so close to the limit, perhaps pushing it further than I even planned to on a conscious/unconscious level, who knows but let's not get all Freud here cause conscious mental activity is rarely true to real events as recorded by history itself anyway, as we all know I am sure, even at an age where so many believe their own indoctrination and simplify everything in a good vs bad camps. Psychology always been a interesting field to me and especially mirroring, reflections of how we see ourselves, how others see... etc..

But old Sigmund may be correct cause in my Childhood, teens and early adult years even I did had my bikes and my team on the competition days, heck had trails outside home and bikes everywhere 3 guys riding who lived there, the clubs local dirt track was just kms away really + my friends personal track a further 10km as well or so and more or less unlimited access to satisfy the needs for violent adrenaline dumps. May be a relic from those days, my behavior or I simple was always that person and never went away, I do have tendencies to ride/drive hard at times no matter what vehicle I end up/on/inside and always bring out a smile and stress reliving to take it to it's maximum capacity, just part of life or insane, well others can be the judge but I am not totally stupid I do understand there is risks involved here and have no desire to get hurt whatsoever. God knows I crashed a few let's just say, sometime you hammer a tree at barely 15mk/h and must fight to catch your breath back after hitting the chest plates, other times you just roll the throttle a tad too much in the air after going fork first down and somehow you just magically walk away after touch down anyways?

Yes there is a chance I could not walk away immediately, or even die let's get aggressive with the potentials, scenarios?  But I really enjoy it, outside this I do more or less nothing but work and a few hours of sleep and been like that for a while now, this is the escape and living in apartment now, no bikes, not even a car apart from at work, for work. The EUC is fantastic cause it can be dragged up the stairs, taken on the train, on the bus and even locked into one of my lockers at work in the morning + it's very fun. Going fast on them is so different from bikes and a lot less pressure points for manipulations + these days I am old, fat and slow so reaching like a 15 year old Red Bull pro skater is out of the question hahaha,  but just as fun in it's own way, point is I need it. Risks sure, accepting them, yes and no.

I accept risks, we all do if we ride. Question is how close to the limit am I prepared to go, I cannot wait til safety get better in these wheels, able to take them as close to full capacity as can get without power suffering, difficult equation due to the nature of the technology I get that, alternative right now it the take up the limit so that it's possible to ride 60km/h and still have reserves, only then I get close to those reserves so damned if you do, damn.. catch 22 in a way.  The main limiting feature of the MSX that I see is by far the power, the wheels feels amazingly calm and behaved even at 50-60km/h so right up to top speed let's say, there will be a point, a cross over where you feel a better construction is needed, perhaps even go full suspension instead and maybe it can help with power cut hitting a small hole already at full or near full capacity?

But yeah getting too much sidetracked here, yes I should back off just a tad more and have more margins on my side that's a good idea, but I am also very sick, the 80% warning and truly respecting it have served me very well so far but a those speeds and wearing full equipment incl the TSG Carbon on my head and visor down it is hard to hear it at times I admit, so look a lot at the WheelLog app to and right now searching for the best solution to truly force the warnings through somehow? Looking at HUD solutions, smart watches and amplifying the audio warning into my helmet, we will see but the way I look at now the highest danger atm is missing a warning, maybe one that came earlier than expected cause while riding like I do I have the greatest respect for that due to Gotway inherent design.

Not sure what I do to make text come out like a book, perhaps I have difficulties wrapping something up up, or short precise explanations?

Maybe I just don't have any friend not sure?