Oversped my ACM (but I'm okay)

[noisycarlos]

Today I was riding on a small mountain road and my ACM almost gave out. Well, technically it gave out, but just for a second, and after some serious wobbling back and forth, I was able to stay on it and keep going for a couple hundred feet, until it was safe to pull over.

Immediately looking at the WheelLog curves I found the culprit... me, for the most part.

The buzzer in my wheel is going bad (sounds like it got some water), sometimes the beeps are really weak and I don't hear them. So I didn't realize I was going 27.2mph... slightly uphill... on my 820wh ACM...  at 55% battery... I know.

Luckily nothing happened, I kept riding for 8 more miles until I made it home just fine. I did turn on the speed notification so my Pebble vibrates, in case I don't hear the speaker.

Just wanted to share what happened for reference. I have to say, even though the battery gave out, I'm impressed it didn't completely failed.

I took some screenshots of WheelLog. One is the summary at the end of my ride, and the curves are the 'incident' from when I started riding a block back to when I pulled over. There's also a closer look at the curves of just the incident. The big peak in the middle is when it gave out, you can see the speed and amps dropping (I wish you could see my face and wobbles too). 

@Marty Backe I guess I really need that 1600Wh now, or you know.. just slow down.

 

[Marty Backe]

1 hour ago, noisycarlos said:

Today I was riding on a small mountain road and my ACM almost gave out. Well, technically it gave out, but just for a second, and after some serious wobbling back and forth, I was able to stay on it and keep going for a couple hundred feet, until it was safe to pull over.

Immediately looking at the WheelLog curves I found the culprit... me, for the most part.

My speaker is going bad, sometimes the beeps are really weak and I don't hear them. So I didn't realize I was going 27.2mph... slightly uphill... on my 820wh ACM...  at 55% battery... I know.

Luckily nothing happened, I kept riding for 8 more miles until I made it home just fine. I did turn on the speed notification so my Pebble vibrates, in case I don't hear the speaker.

Just wanted to share what happened for reference. I have to say, even though the battery gave out, I'm impressed it didn't completely failed.

I took some screenshots of WheelLog. One is the summary at the end of my ride, and the curves are the 'incident' from when I started riding a block back to when I pulled over. There's also a closer look at the curves of just the incident. The big peak in the middle is when it gave out, you can see the speed and amps dropping (I wish you could see my face and wobbles too). 

@Marty Backe I guess I really need that 1600Wh now, or you know.. just slow down.

 

I haven't paid much attention to those plots before. The Y-axis is in km/h. You're pretty confident that you were going 27mph? That really does seem hard to believe with your version of the ACM.

You are so much into speed now I really think for your safety you should get the 84v version sooner rather then later 

Those buzzers (not actually speakers) are readily available and easily swapped. You should probably get one.

[zlymex]

- I've just confirmed the display bug(of Wheellog that it display km/h even set to MPH)

- Riding ACM at 27mph is very dangerous as the lift speed of ACM is merely 30mph or so. I saw a video a guy riding ACM on flat road and fell at 27mph(43kmh) http://v.youku.com/v_show/id_XMTYwMDgyNDc0NA==.html
There is another test with top speed fall at 44.9kph(27.9mph).

- I suggest to set speed warning(in Wheellog) of not over 25mph and set over current warning of 50A and enable the vibration.

[noisycarlos]

2 hours ago, Marty Backe said:

I haven't paid much attention to those plots before. The Y-axis is in km/h. You're pretty confident that you were going 27mph? That really does seem hard to believe with your version of the ACM.

You are so much into speed now I really think for your safety you should get the 84v version sooner rather then later 

Those buzzers (not actually speakers) are readily available and easily swapped. You should probably get one.

Thanks. Updated my post to 'buzzer' :-D Also looking to get replacements online. Just gotta open it to see the voltage it needs, I'm guessing 12v.

Yeah, the km/h is a bug, kph is the default and when you change it to mph it doesn't change it in the graph. Plus, on the summary it says 27.4 mph, and I didn't lift it.

It's funny, I was taking a leisure ride and I didn't think I was going fast. But I was sharing the road with cars and it was a very smooth road, so it felt I was going less than 20.

[noisycarlos]

35 minutes ago, zlymex said:

- I've just confirmed the display bug(of Wheellog that it display km/h even set to MPH)

- Riding ACM at 27mph is very dangerous as the lift speed of ACM is merely 30mph or so. I saw a video a guy riding ACM on flat road and fell at 27mph(43kmh) http://v.youku.com/v_show/id_XMTYwMDgyNDc0NA==.html
There is another test with top speed fall at 44.9kph(27.9mph).

- I suggest to set speed warning(in Wheellog) of not over 25mph and set over current warning of 50A and enable the vibration.

Thanks.
I set the new alarms at 18mph (with 60% battery or less), 22mph and 24mph. I completely didn't realize I was going 27mph, so I wanna make sure I'm within safety limits.

I couldn't play the video, but I did a lift test on my wheel... 32.6mph. I wonder what it is on an MSuper.

[zlymex]

10 minutes ago, noisycarlos said:

I couldn't play the video, but I did a lift test on my wheel... 32.6mph. I wonder what it is on an MSuper.

I tested the lift speed of my MSuper V3 to be 33.3mph(full battery). However, the 84V version*V3s+( is much higher at 42.6mph.

Here is the screen shot of the video just before the fall.

[Chriull]

3 hours ago, noisycarlos said:

Today I was riding on a small mountain road and my ACM almost gave out. Well, technically it gave out, but just for a second, and after some serious wobbling back and forth, I was able to stay on it and keep going for a couple hundred feet, until it was safe to pull over.

Grats! Great you "survived" this without even a scratch!

3 hours ago, noisycarlos said:

Immediately looking at the WheelLog curves I found the culprit... me, for the most part.

The buzzer in my wheel is going bad (sounds like it got some water), sometimes the beeps are really weak and I don't hear them. So I didn't realize I was going 27.2mph... slightly uphill... on my 820wh ACM...  at 55% battery... I know.

Luckily nothing happened, I kept riding for 8 more miles until I made it home just fine. I did turn on the speed notification so my Pebble vibrates, in case I don't hear the speaker.

Just wanted to share what happened for reference. I have to say, even though the battery gave out, I'm impressed it didn't completely failed.

Most likely it was not your battery giving out - you just reached the limit of your wheels possibilitys, also the graph seems a bit strange, or better said - i don't really understand the lines by now...

3 hours ago, noisycarlos said:

I took some screenshots of WheelLog. One is the summary at the end of my ride, and the curves are the 'incident' from when I started riding a block back to when I pulled over.

Impressive acceleration at the beginning  - from 0 to 20 mph within less than a second!

3 hours ago, noisycarlos said:

There's also a closer look at the curves of just the incident. The big peak in the middle is when it gave out, you can see the speed and amps dropping (I wish you could see my face and wobbles too). 

What's strange at this curves (at least for me) is, that at the time of the speed peak the current is just steadily rising, and at the current peak you where already breaking!

The curves seem almost like a bit time shifted... ;(

It just could be, that the ACM does not report negative (regenerative) currents to wheellog and that at the speed peak also the current peak was reached (current-speed limit of wheel reached), you braked quite immedeately and the "real" diagramm should show a negative current spike for regenerative braking...

3 hours ago, noisycarlos said:

@Marty Backe I guess I really need that 1600Wh now, or you know.. just slow down.

 ... but there will still be a limit - just a bit higher ...

 

[meepmeepmayer]

Very nice summary with pictures and everything. Glad you managed to catch the overlean. And you always seem to be padded up well

27 mph on a 67V ACM? Uphills?  No wonder this happened.

May I ask the approximate incline %, and what's your weight?

Also I think you just need a Monster. Fast, stable, quite good on hills too, seems like the right wheel for you. No point in getting a 84V ACM if you like these kinds of speeds, at 50 km/h (31 mph) ACMs have some emergency accelerating behavior/tiltback (not sure what it's like while on the wheel) that I'm pretty sure you do NOT want to encounter while riding.

[Rehab1]

5 hours ago, Marty Backe said:

My speaker is going bad, sometimes the beeps are really weak and I don't hear them. So I didn't realize I was going 27.2mph... slightly uphill... on my 820wh ACM...  at 55% battery... I know.

I could barely hear the constant beeps going off on my ACM 1600 while riding around on the proving track on Friday. It was purely related to speed. 

 

6 hours ago, noisycarlos said:

 I did turn on the speed notification so my Pebble vibrates, in case I don't hear the speaker.

The pebble is definitely my next purchase! I need a vibratory feedback instead of the low decibel beeper!

[noisycarlos]

1 hour ago, meepmeepmayer said:

Very nice summary with pictures and everything. Glad you managed to catch the overlean. And you always seem to be padded up well

27 mph on a 67V ACM? Uphills?  No wonder this happened.

May I ask the approximate incline %, and what's your weight?

Also I think you just need a Monster. Fast, stable, quite good on hills too, seems like the right wheel for you. No point in getting a 84V ACM if you like these kinds of speeds, at 50 km/h (31 mph) ACMs have some emergency accelerating behavior/tiltback (not sure what it's like while on the wheel) that I'm pretty sure you do NOT want to encounter while riding.

Yup, I pad up. Other than a few extra pounds, I like my current body configuration :-)

The hill wasn't very steep, maybe 5-10%, but this happened on my way back so the battery was down to 55%ish, my weight it's 190lbs (86kg). 

ACMs have tilt back, but it can be turned off (mine is turned off), I think the monster and msuper are the same.

I use my wheel every day and bring it to the coffee shop, grocery shopping, etc. So the monster might be too much, but I would consider an Msuper. 

I must note,I wasn't trying to go that fast, I just didn't realize because the cars were going faster, the road was super smooth and the aforementioned unheard buzzer.

[Marty Backe]

3 hours ago, Rehab1 said:

I could barely hear the constant beeps going off on my ACM 1600 while riding around on the proving track on Friday. It was purely related to speed. 

 

The pebble is definitely my next purchase! I need a vibratory feedback instead of the low decibel beeper!

The Pebble watch is my favorite piece of riding tech. The ability to configure it to buzz based on speed is very nice. As you've noted you can't always hear the buzzer but you always feel the buzz on your wrist.

[Marty Backe]

2 hours ago, noisycarlos said:

Yup, I pad up. Other than a few extra pounds, I like my current body configuration :-)

The hill wasn't very steep, maybe 5-10%, but this happened on my way back so the battery was down to 55%ish, my weight it's 190lbs (86kg). 

ACMs have tilt back, but it can be turned off (mine is turned off), I think the monster and msuper are the same.

I use my wheel every day and bring it to the coffee shop, grocery shopping, etc. So the monster might be too much, but I would consider an Msuper. 

I must note,I wasn't trying to go that fast, I just didn't realize because the cars were going faster, the road was super smooth and the aforementioned unheard buzzer.

I don't think there's much difference between the MSuper & ACM in terms of max speed. So if you prefer the smaller form factor the ACM will still satisfy your speed desires

[Pard]

 

You were very lucky.  Right on the edge of a face plant!

I found it very worthwhile to develop a sense of wind speed and wind noise correlated with speed.

I started off looking at my phone to gauge speed, but that is really dangerous and distracting.

Practice the art of knowing how fast you are going to within a few mph based on sensation alone.

 

IMHO

 

[Hunka Hunka Burning Love]

That's why I kind of like the tiltback feature.  It sort of introduces a deterent of trying to go faster than you should.  People have had problems of setting it too high so when it triggers that extra speed burst and current demand the BMS cuts out so you have to set it wisely with some room to spare.  I don't know if maybe the tiltback is too unsettling on the Gotways, but the Ninebot it's pretty well thought out and never made me feel like falling.  Could be the low speed difference maybe?

I guess think of it as a guardrail on the edge of a cliff versus a quiet beeper that warns you if you get too close to the fall off point.

[meepmeepmayer]

12 minutes ago, Hunka Hunka Burning Love said:

Could be the low speed difference maybe?

That must be it

I would never deactivate tiltback as well. It's there for a reason. Set it a bit higher than your safe (for the weight) max speed, and you will be warned of danger AND you have good motivation to not overspeed, in order to not hilt that dreaded (dangerous?) tiltback.