Top speed of 84v Monster V2

[Slartibartfast]

Anyone know what speed the Gotway Monster V2 is meant to be able to achieve?

I've ridden at 50 km/h several times and all seemed perfectly in control but on a straight and relatively secluded path I decided to push it upto 55km/h, but overshot by a little and at 56km/h the wheel completely shutdown on me! Is that meant to happen?

I thought there was meant to be a tilt back at 80% of capacity or something but there was absolutely nothing. Just felt it switch off, then waited till impact. Is this normal?

[alcatraz]

Whatever speed it has in a pickup test, reduce that by around 20km/h and that's the top speed on a flat road without crazy head wind. If you're a heavy rider then reduce by more than 20.

If you usually accelerate quickly to your cruising speed then reduce by more than 20. Top speed is not something you push hard to achieve. 

If you ride on crappy roads reduce that max speed. One tiny speed bump and it could shut off by the sudden power draw.

The level of charge also plays a big role. Turn tiltback back on. Test it at a low speed to see that it works. Also check your alarm that it works.

Edited January 21, 2022 by alcatraz

[Chriull]

9 minutes ago, Slartibartfast said:

Anyone know what speed the Gotway Monster V2 is meant to be able to achieve?

The Monster (v1) had the third speed alarm (80% alarm ?) at 45-55km/h depending on battery voltage.

9 minutes ago, Slartibartfast said:

I've ridden at 50 km/h several times and all seemed perfectly in control but on a straight and relatively secluded path I decided to push it upto 55km/h, but overshot by a little and at 56km/h the wheel completely shutdown on me! Is that meant to happen?

Yes, depending on battery state and burden (incline, acceleration). Sounds like normal overlean.

9 minutes ago, Slartibartfast said:

I thought there was meant to be a tilt back at 80% of capacity or something but there was absolutely nothing. Just felt it switch off, then waited till impact. Is this normal?

There should be alarm beeps, but they are easily overheard. Tiltback seems to be disabled with most gw - you'd have to enable it again.

But tiltback is only for a fixed speed and not battery and burden dependend, so that's no real safety measure.

And some reported afair that gw tiltbacks can be very duscomforting - so one should try that before at lower speeds.

[Slartibartfast]

I certainly didn't mean to disable the tilt back but it seems I may have somehow inadvertently done so.

As it was the wheel was riding very nice and stable and I didn't feel at all close to the edge... till I went over it: 

 

Just did a free spin test and it reached 72 km/h. At the time of the crash the battery was at about 85%.

Edited January 23, 2022 by Slartibartfast

[Slartibartfast]

This is a speed/current plot of the accident:

[Chriull]

5 minutes ago, Slartibartfast said:

I certainly didn't mean to disable the tilt back but it seems I may have inadvertently done so some how.

Afair if it's set to zero it's disabled.

5 minutes ago, Slartibartfast said:

As it was the wheel was riding very nice and stable and I didn't feel at all close to the edge... till I went over it: 

That's the unfortionately absolutely unintuitive thing about overleans - the is no engine noise telling one the overburden or any other sign that one reaches the limit. It comes absolutely instant without warning.

There is just some chance, if one is alert to feel the pedals start to get a bit softer before overlean. This could maybe be explained by burden not beeing really constant. So if burden fluctuates in reality rapidly some, for example +/-5% around the average the peak percent could already be over the overlean limit while the other 9% are well within the wheels ability. As crossing this max torque limit does not mean motor shutdown but just that less than the needed torque can be delivered this should feel like pedals getting softer/weaker. Only once average burden crosses the limit without riders reaction one overleans...

Here was a report of one who stood an overlean because he did not lean forward to accelerate but only put pressure on the pedals with his forefoot. So he "stood stable" above the wheel and just needed to take away the "forefoot pressure" to stop the overlean.

Don't have any idea if this a one out of hundred chance to perform like this or a real thing one could learn?

What should help is crouching (and tight closing;)- minimizing air attack surface. If one tries finding max speed on a nicely paved road without inclines and accelerates very decently wind resistance is the main burden that limits max speed.

And of course try this with a full battery;

5 minutes ago, Slartibartfast said:

Just did a free spin test and it reached 72 km/h. At the time the battery was at about 85%.

72 km/h lift cut off speed at 85% mean ~72/85*100=84km/h at 100%! As the reported 100% are a wide range, this 84 km/h are only for the "lower 100%" limit. At the upper 100% limit it should be even a bit higher...

So, if you overleaned with ~85% at 56km/h you could have reached ~56/85*100=65 km/h! (A bit less in reality as air resistance grows not linear).

This number is very close to @alcatraz "20 km/h rule of thumb"!

 

[Chriull]

15 minutes ago, Slartibartfast said:

This is a speed/current plot of the accident:
 

If you have the data logged as csv you very likely can see nicely the overlean if you plot (phase/motor) current vs speed like in this post the second graph:

One sees nicely the max torque (current) over speed limit on the right side that cannot be crossed...

In the first post of this topic is an overlean with much more lines/limits/etc shown...

[Nick McCutcheon]

This sounds more like a cutout than an overlean. I had a similar experience on my Sherman, I flew too close to the sun at 50% battery and the wheel decided to disengage the motor at 47mph. I am certain it wasn't an overlean, as the ground was totally flat and I had felt the pedals were still stable/didn't dip when doing little micro-accelerations. After the cutout it was pretty damaged but I was able to ride back home.

I can't believe this is still an issue on modern wheels, it's so easy to solve in software. If not a lot of current being drawn but at top speed, shut motor off since it's a lift test. If a lot of current being drawn but near top speed, do not shut motor off as someone is riding. Seems like a very simple solution, if I knew more about STM I would mod the Sherman firmware to fix this..

[supercurio]

Kind of a stupid question @Slartibartfast, but does you wheel beeper work?
Your story sounds like (no pun intended) the beeper is not operational, or you were not able to hear it (which is very frequent)

Any over-lean and (abnormal) cut-out will likely feel the same, aside from the auditory alert.

[supercurio]

58 minutes ago, Nick McCutcheon said:

This sounds more like a cutout than an overlean. I had a similar experience on my Sherman, I flew too close to the sun at 50% battery and the wheel decided to disengage the motor at 47mph. I am certain it wasn't an overlean, as the ground was totally flat and I had felt the pedals were still stable/didn't dip when doing little micro-accelerations. After the cutout it was pretty damaged but I was able to ride back home.

Glad you were able to make it back home.

47 mph at 50%, the Sherman must have been beeping persistently.
I'm almost surprised you could reach that speed at this battery level - I wouldn't dare.

BTW I hope we can convince Leaperkim to add beeper status over Bluetooth data like Begode does since MSP times, which allows to have an app relay the wheel alarms over a Bluetooth speaker. On the Sherman with a seat installed and some wind or ambient noise, you can absolutely miss it.

[Freestyler]

While we are at it, please convince begode to add tiltback at the 80% speed.

The mechanisms are there already. 

80% voltage dependant speed alarm and tiltback exist. They just need to apply it dynamically at the same speed as the 80% alarm.

It does not handle all the situations of course (like the 80% can't), but it will save a lot of people...

It can of course be disabled like people disable the 1st & 2nd fixed speed alarms, but it will ship enabled by default.

Edited January 21, 2022 by Freestyler

[supercurio]

13 minutes ago, Freestyler said:

While we are at it, please convince begode to add tiltback at the 80% speed.

The mechanisms are there already. 

80% voltage dependant speed alarm and tiltback exist. They just need to apply it dynamically at the same speed as the 80% alarm.

It does not handle all the situations of course (like the 80% can't), but it will save a lot of people...

It can of course be disabled like people disable the 1st & 2nd fixed speed alarms, but it will ship enabled by default.

Unfortunately I'm not aware of any way to convince Begode of anything, especially after hearing stories from very influential, high market share distributors which couldn't get anything through despite reasonable requests.

I agree that it would be a sensitive request however, and could possibly have avoided @Slartibartfast's high speed crash. Although it appears notoriously hard to implement a fool proof and reliable tiltback mechanism which works well even during strong accelerations.

The Leaperkim target seems more achievable as they have a presence on social media who seem to provide support and send replacement parts directly to influencers or customers who experienced issues (so that could be a way to reach out)

If anybody has a way to reach out to Begode tho, please speak up! This type of crash shouldn't happen anymore.

Edited January 21, 2022 by supercurio

[LanghamP]

These top speed threads are akin to asking how many punches can you take from a professional heavyweight boxer.

Here, just get on your EUC, and keep leaning forward to see what happens.

 

[Freestyler]

I also agree that having a tiltback that also accounts for available torque is more difficult, but the good thing with most of the new begode wheels (4 parallel packs and up) is that they are strong enough to rarely get overtorqued, unless the rider is doing extreme leans and / or overweight.

The usual cutoff reason is overspeed, by ignoring / not hearing the beeps.

So just starting by applying the tiltback (that already exists as a functionality in the wheel) in the established 80% speed alarm, is a very good starting point with minimal changes required. (Heck, we could even simulate it by dynamically set the tiltback through apps, but unfortunately we can't change settings while riding)

It might not save someone doing donkey leans, but it will definitely save unsuspected riders who slowly creep up to speeds trying to find the limits.

Edited January 22, 2022 by Freestyler

[supercurio]

20 minutes ago, Freestyler said:

I also agree that having a tiltback that also accounts for available torque is more difficult, but the good thing with most of the new begode wheels (4 parallel packs and up) is that they are strong enough to rarely get overtorqued, unless the rider is doing extreme leans and / or overweight.

The usual cutoff reason is overspeed, by ignoring / not hearing the beeps.

So just starting by applying the tiltback (that already exists as a funtionality in the wheel) in the established 80% speed alarm, is very good starting point with minimal changes required. (Heck we could even simulate it by dynamically set the tiltback through apps, but unfortunately we can't change settings while riding)

It might not save someone doing donkey leans, but it will definitely save riders who slowly creep up to speeds trying to find the limits.

Yes agree: tiltback getting close to max speed before running out of torque is feasible and can be excellently done.

Despite shortcomings on safety and alarms, on the Kingsong 16X the max speed tiltback specifically is spot at 50 kph / 31 mph.

You can't miss it, it's not scary, doesn't tilt too much too quickly, it disables itself instantly based on rider input which makes it very interactive. So there's no doubt it can be done.

How has been the Gotway tiltback in your experience, and how does hard/medium/soft affect it?

Edited January 22, 2022 by supercurio

[Tawpie]

A Gotway that actually tilts back? Perish the thought. Blasphemy. Heresy. Get thee behind me.

[Nick McCutcheon]

2 hours ago, supercurio said:

Glad you were able to make it back home.

47 mph at 50%, the Sherman must have been beeping persistently.
I'm almost surprised you could reach that speed at this battery level - I wouldn't dare.

BTW I hope we can convince Leaperkim to add beeper status over Bluetooth data like Begode does since MSP times, which allows to have an app relay the wheel alarms over a Bluetooth speaker. On the Sherman with a seat installed and some wind or ambient noise, you can absolutely miss it.

I actually added a killswitch for the beeper 😅 It starts beeping at 41-42mph at 100% while my safe top speed from 100% down to 50% is usually 48mph down to 46mph, so it beeps constantly when you're using the Sherman at the high speeds it was made for. The reason I cut out is because I upped my "speed limit" at 50% to 47mph rather than my usual 46 that day in EUC world, and I was actually probably closer to 40% thinking back. I have it set up to alarm at 48mph at 100%-50%, 46mph at 50%-25%, and 44mph at 25%-0% and have never cut out with these settings. I thought I could push it a bit farther but I thought wrong! Haha. 

I wish they had decided to go for a higher safety margin than 70% as opposed to GW's 80% for the beeper so it would actually be a useful indicator, though I understand why they did it. 

If a measurably faster wheel comes out, I'm getting it. I decided against the marginally faster Monster Pro as it's really not usable for going in and out of shops which I do often with the Sherman. Fingers crossed for the V13 or whenever GW decides to put their new 116v boards (yes I know it would be closer to 117.6v in practice with Li ion cells) to good use with a C30 motor! 

The only reason I haven't purchased a super high end escooter like the Bronco or even just a regular motorcycle is because the portability to performance ratio of EUCs is unmatched with no registration needed and cops are more likely to know what a scooter is and crack down on the super fast ones. Most places won't care if I bring what looks like a suitcase with a big wheel inside, but I'm sure they would have some qualms with a big honking scooter that weighs a lot more than even the heaviest EUC.

Edited January 22, 2022 by Nick McCutcheon
More context

[Freestyler]

25 minutes ago, supercurio said:

How has been the Gotway tiltback in your experience, and how does hard/medium/soft affect it?

The most experience I had was with the v11. The tiltback was reliable, but never startling. Here is is a clip of me riding constantly on a mild tiltback.  (it increases more with speed, but at 55 there is no much room to push)

 

On the monster sport, well... I wasn't fortunate enough to experience it. 😅

 

And now on my mcm5v2, I rarely push more than 30km/h because of the small tire and the wheel beeps at 47km/h at full charge and 36km/h at 10% battery, so lots of buffer there.

I plan to test it more, but from some initial tests, I got the impression that it it ramps up slowly and it is easy to overshoot the speed. The 70% (instead of 80%) beep on the Sherman should give it more margin.

I will also buy a RS HT soon, so I'll test it there as well 😛

Edited January 22, 2022 by Freestyler

[Slartibartfast]

2 hours ago, supercurio said:

Kind of a stupid question @Slartibartfast, but does you wheel beeper work?
Your story sounds like (no pun intended) the beeper is not operational, or you were not able to hear it (which is very frequent)

Any over-lean and (abnormal) cut-out will likely feel the same, aside from the auditory alert.

Not a stupid question at all. As it is my alarms don't actually work. I had an unfortunate incident where this wheel powered on while in shipping and ended up cracking it's shell, so when I replaced the shell I upgraded to a Monster V3 shell (carbon fiber with the battery level indicator).

Although the "upgrade kit" was meant to be a simple plugin unfortunately the V2 board doesn't actually support the battery output so this never worked. Also as part of the upgrade I could never get the piezoelectric buzzer (or whatever it is) working. The Bluetooth speakers work fine and I hear the power up melody and voice perfectly however the warning beeps don't seem to work, not sure if it's related. In any event though it seems unlikely one would be able to hear such beeps at 50 km/h regardless.

As it was I somehow had the "Too fast" warning set to just 25 km/h in EUC World and this did come through nice and clear in my Bluetooth earbuds. Once I realised it was set to 25 I set it to 55 km/h and was trying to trigger it when the wheel cutout.

As I say I wasn't actually trying to push the limits of the wheel at the time. Although I didn't really think about it I just kind of thought the Monster was capable of much higher speeds than this. As I say I've tipped up to 50 km/h several times and was just going a little higher. Had I known I was approaching the limits I would have been much more cautious.

[Slartibartfast]

46 minutes ago, supercurio said:

How has been the Gotway tiltback in your experience, and how does hard/medium/soft affect it?

I have tiltback set to something like 40 km/h on my 84V MSX and it works well. You can scarcely feel it at it's activation speed but becomes more and more noticeable as you increase. I've intentionally pressed through the tilt back in my MSX up to 51 km/h on one occasion and it behaves as expected. It's actually a really good feature, I just had no idea I was so close to the limit with these speeds. I don't think having the mode set to "hard", "medium" or "soft" makes any difference.

Edited January 22, 2022 by Slartibartfast

[Slartibartfast]

Curiously, after looking at the CVS data it appears that after the wheel cutout I just picked it up and rode it home. As in it didn't shut down or anything.

The plot clearly shows the wheel hitting 56.19 km/h, plummeting to zero, then being ridden home a few minutes later without being reset in between. Not shore if that means anything but it seems I didn't even turn it off after the crash: 🤷‍♂️

[Slartibartfast]

Hmm, looking more at the data I see there is a mysterious column called "safety_margin". While at rest this value is 100 and as speed increases this value drops, until at 56.19 km/h this value drops all the way to 2! Looks like someone knew I was pushing the limits even though I didn't.

[mrelwood]

Your unfortunate experience is yet another example why a dynamic top speed tilt-back should absolutely be a feature on GW/BG/Veteran wheels as well. An uninformed overspeed crash like that simply can’t happen on KS and Inmotion wheels.

 The tilt-back on the 84V MSX at least was very gentle and smooth, and if anything it was maybe too gentle. It never felt like a tilt-back, but more like an increasing headwind, where you would need to push much more to go faster. I would never push through a that kind of feeling at 50km/h, so it worked very well for me.

 What GW/BG/Veteran needs to add is:

- Tilt-back value selectable at least up to the 80% beep speed.

- Tilt-back value selectable by smaller increments than the current 3km/h (~2mph).

- Tilt-back speed adjusting dynamically with decreasing battery level, as well as the power usage level.

 Personally I also think that this final top speed tilt-back should not be user-removable. It’s easy for the onboard computer to calculate the remaining buffer, but it’s impossible for the rider to do the same, hence the responsibility to do so should never be on the rider.

 Unfortunately the manufacturer doesn’t seem to care at all about incidents like this, no matter how badly the rider was hurt. *shrugs*

[Chriull]

6 hours ago, Slartibartfast said:

As it is my alarms don't actually work. I had an unfortunate incident where this wheel powered on while in shipping and ended up cracking it's shell, so when I replaced the shell I upgraded to a Monster V3 shell (carbon fiber with the battery level indicator).

You could try @supercurio's euc alarm App 

5 hours ago, Slartibartfast said:

Hmm, looking more at the data I see there is a mysterious column called "safety_margin". While at rest this value is 100 and as speed increases this value drops, until at 56.19 km/h this value drops all the way to 2! Looks like someone knew I was pushing the limits even though I didn't.

Safety Margin originally came from KS wheels reporting the pwm duty cycle which is effectifely how much of the available possibe power/torque of the wheel is used in 0-100%. Safety margin is 100% - pwm duty cycle.

Inmotion now reports this value too since some time.

For GW/Begode this are just estimations. I have now idea how good this estimates are till now. But your reported values would indicate clearly an overlean.

Still the way to know it for sure is to make a motor/phase current vs speed diagram.

[Slartibartfast]

54 minutes ago, Chriull said:

Still the way to know it for sure is to make a motor/phase current vs speed diagram.

I'm not exactly sure what you mean by a "motor/phase current vs speed" diagram, but does this plot help:


I also tried rendering the data as an X-Y Scatter Plot but that doesn't seem to show anything intelligible.