Hills and temperature

[applecran]

I recently purchased a Segway Ninebot One S1 and have had it for about a week. I'm feeling pretty comfortable on it now and have started venturing outside of my neighborhood. Besides this thing having the most confusing marketing and name, and the fact that I need a cooler helmet, I think I'm hooked.

 

I live in a hilly part of town,  and live on a hill. I plan to ride to work which involves about 2.5 km downhill and then the same back up later. Did a test run today and I can easily get the unit up to to top speed even at the steepest part of the ride (about a 10% grade peak).

 

I was monitoring the temps and got the main board up to 62 degrees Celsius at the top of the hill. 

 

I'm wondering if anyone has any ideas as to what temp is to high? Also will the temperature have any effect on breaking ability going downhill?

 

Thanks!

[Hunka Hunka Burning Love]

My Ninebot One E+ gets up to about 53C maximum, but I don't climb a lot of long, steep hills.  Anything below 79C is probably okay I'm guessing.  Difficult to say what the upper limit on an S1 is as it is not mentioned too often on the forums.

Ninebot firmware is pretty smart though (at least the ones that don't blow up the main board ) so hopefully it will start to give warnings if things get too toasty.

[WARPed1701D]

Side note: If your ride starts with a long downhill do not start with a completely full battery or the energy from regenerative braking will have nowhere to go and you may risk a cut out. Ride 5% or so out of the battery first.

[LanghamP]

Won't going veeery slowly down a hill make the engine use up more energy than what can be recovered by regenerative braking?

[US69]

19 minutes ago, LanghamP said:

Won't going veeery slowly down a hill make the engine use up more energy than what can be recovered by regenerative braking?

From my experience: Nope!

Even going very slow recovers enough energy to Charge the Batterie...and when you have reached the Peak of 67,2 Volts(or short before) the wheel will Alarm you and tiltback.

I had that on a KS16 two or three times.

[applecran]

4 hours ago, WARPed1701D said:

Side note: If your ride starts with a long downhill do not start with a completely full battery or the energy from regenerative braking will have nowhere to go and you may risk a cut out. Ride 5% or so out of the battery first.

Hmm, good to know,. I had wondered about this. I wish there was a way to only charge to 95%.

I guess these wheels don't have ability to dissipate that much energy as heat.

Having said that, my first line Hill ride yesterday started at fill battery with 100% charge and i didn't have any cut off.

 

 

[Keith]

12 minutes ago, applecran said:

Hmm, good to know,. I had wondered about this. I wish there was a way to only charge to 95%.

I guess these wheels don't have ability to dissipate that much energy as heat.

Of course there is you just use a charge doctor. These are designed so that they can be set to switch off charging when the current drops to a preset figure.

these wheel do not have any ability to dissipate energy deliberately as heat (I.e. Other than normal thermal losses) the amount of heat braking down hill would generate would be way too high to usefully get rid of. I think at least one person has been working on trying to vector braking energy into car headlight bulbs or similar but, bottom line, unless the battery is completely full putting the energy into back into the battery does make the best sense. 

[LanghamP]

43 minutes ago, applecran said:

Hmm, good to know,. I had wondered about this. I wish there was a way to only charge to 95%.

I use an outlet timer and guess one minute of charging to one minute of riding.

Century smart digital countdown timer with repeat function https://www.amazon.com/dp/B01D3QEK4E/ref=cm_sw_r_cp_apa_eGIDzbCXRARAA

 

[steve454]

6 hours ago, applecran said:

I wish there was a way to only charge to 95%.

On ninebot, I think in one of Speedyfeets videos he turned on the wheel while charging and said as the charge goes up, so do the leds in the light ring.  I know KS has the light ring, you might try leaving it on while charging and see if the leds go up while charging, checking the wheel every so often, and unplugging at the next to the highest leds.  That should be around 90%  However, it might not be possible to charge while the wheel is on, just putting a suggestion out there to try.

[applecran]

6 hours ago, Keith said:

Of course there is you just use a charge doctor. These are designed so that they can be set to switch off charging when the current drops to a preset figure.

these wheel do not have any ability to dissipate energy deliberately as heat (I.e. Other than normal thermal losses) the amount of heat braking down hill would generate would be way too high to usefully get rid of. I think at least one person has been working on trying to vector braking energy into car headlight bulbs or similar but, bottom line, unless the battery is completely full putting the energy into back into the battery does make the best sense. 

 

6 hours ago, LanghamP said:

I use an outlet timer and guess one minute of charging to one minute of riding.

Century smart digital countdown timer with repeat function https://www.amazon.com/dp/B01D3QEK4E/ref=cm_sw_r_cp_apa_eGIDzbCXRARAA

 

 

45 minutes ago, steve454 said:

On ninebot, I think in one of Speedyfeets videos he turned on the wheel while charging and said as the charge goes up, so do the leds in the light ring.  I know KS has the light ring, you might try leaving it on while charging and see if the leds go up while charging, checking the wheel every so often, and unplugging at the next to the highest leds.  That should be around 90%  However, it might not be possible to charge while the wheel is on, just putting a suggestion out there to try.

Thanks Folks, super helpful.  I'll order up a charge Dr, seems like a nice hands off approach.

 

 

[zlymex]

I've measured in several instances that if an uphill consume 3Wh(on a roughly 10% slope), then an 1Wh will be recovered(charged to the battery) if down the same hill.

Therefore, if an overcharge is experienced on a downhill trip, you can just go back(uphill) for some distance, then you are able to ride down for approximate three times the distance(twice the distance from the retracing point). Repeat this procedure will allow any long distance downhill be conquered, provided the wheel is not overheated.

[applecran]

10 hours ago, zlymex said:

I've measured in several instances that if an uphill consume 3Wh(on a roughly 10% slope), then an 1Wh will be recovered(charged to the battery) if down the same hill.

Therefore, if an overcharge is experienced on a downhill trip, you can just go back(uphill) for some distance, then you are able to ride down for approximate three times the distance(twice the distance from the retracing point). Repeat this procedure will allow any long distance downhill be conquered, provided the wheel is not overheated.

Thanks!

[applecran]

On 7/24/2017 at 4:49 AM, WARPed1701D said:

Side note: If your ride starts with a long downhill do not start with a completely full battery or the energy from regenerative braking will have nowhere to go and you may risk a cut out. Ride 5% or so out of the battery first.

Hmm, good to know,. I had wondered about this. I wish there was a way to only charge to 95%.

I guess these wheels don't have ability to dissipate that much energy as heat.

Having said that, my first line Hill ride yesterday started at fill battery with 100% charge and i didn't have any cut off.

 

 

[applecran]

So today was my first commute to work. Morning was decent, I learned that my brain is not ready for balancing in the morning, took a while to get into it while I drained off some battery power before heading down the hill.

Went for lunch on the wheel which was a nice change of pace.

I may have found the temp limit on the main board on the way home. First 3km home is all flat, slow bike trails avoiding bumps in the surface from tree roots, dogs and people. Then we get to the hill.

 

Start heading up the hill, it's in two stages, go up about 450 meters, take a left on a flat surface for about 150 meters , then the last 300 meters. Near the top of the second section the ninebot started beeping . I got off, checked the temp and it was 66.7 Celsius on the main board. Turned it off, Waited a couple of minutes and turned it back on, 64celsius and no beeping. I went on my way and made it home without problems.

When I got home I noticed the car at the top in one spot was warm, assuming that is where the battery is. I also smelly a faint smell of hot electronics from the wheel. 

Good news is it seems it won't charge until the unit cools sufficiently.

Now I'm wondering if I just need a bigger wheel. I'm 210lbs so nearing the limit of the wheel.

There is another route I can take that is longer but half the grade. It's also not as quiet or as nice a ride.

Would a higher powered wheel do better here or would I have similar problems?

 

[WARPed1701D]

You are on the heavier end of the acceptable weight range for the One S1 and it is not a wheel with a particularly strong motor.  I would say you are probably pushing it to its limits, especially with the prolonged hill climb.

In hindsight a higher power wheel would probably have been a more appropriate choice.

[applecran]

4 hours ago, WARPed1701D said:

You are on the heavier end of the acceptable weight range for the One S1 and it is not a wheel with a particularly strong motor.  I would say you are probably pushing it to its limits, especially with the prolonged hill climb.

In hindsight a higher power wheel would probably have been a more appropriate choice.

Yeah hindsight... this was an impulse buy on Amazon Prime day!  

 

I think what you re saying (besides the obvious that I could loose a few  ) is that a more powerful wheel won't have the same problems as this one. That makes sense to me I just wanted to be sure after watching @Marty Backe fall off his Gotway going up a hill. Maybe that one was steeper?  I want to make sure what I'm trying to do - commute from my house on a hill to work and back - is possible on ANY wheel before I go invest in a new wheel.

I'm hooked on this form of transport, it's fun, and for a fat slightly overweight beer lover, it's actually a bit of exercise, I'm hoping that I can find a way to make this work!

 

[Marty Backe]

43 minutes ago, applecran said:

Yeah hindsight... this was an impulse buy on Amazon Prime day!  

 

I think what you re saying (besides the obvious that I could loose a few  ) is that a more powerful wheel won't have the same problems as this one. That makes sense to me I just wanted to be sure after watching @Marty Backe fall off his Gotway going up a hill. Maybe that one was steeper?  I want to make sure what I'm trying to do - commute from my house on a hill to work and back - is possible on ANY wheel before I go invest in a new wheel.

I'm hooked on this form of transport, it's fun, and for a fat slightly overweight beer lover, it's actually a bit of exercise, I'm hoping that I can find a way to make this work!

 

The hill where my ACM failed was extremely steep, and it was a trail - not easy to ride and therefore I was going slow. If you are going up a paved road I can't imagine you having problems. You'll be traveling faster which consumes less power. Use Google Earth to determine the slope of your commute route. I doubt that it's 25+ %, but who knows.

[applecran]

25 minutes ago, Marty Backe said:

The hill where my ACM failed was extremely steep, and it was a trail - not easy to ride and therefore I was going slow. If you are going up a paved road I can't imagine you having problems. You'll be traveling faster which consumes less power. Use Google Earth to determine the slope of your commute route. I doubt that it's 25+ %, but who knows.

thanks that was helpful!  Looks like my two possible paths both range in slope, the route I'm using ranges from about 8 degrees to 25 degrees in slope, the other from about 3 degrees to 25 degrees in slope.  So either way, I'm definitely pushing the ninebot to the extreme... sigh.  I guess I may need to drive down the hill for now while I investigate another wheel.

 

Thanks Marty.

[WARPed1701D]

4 hours ago, applecran said:

Yeah hindsight... this was an impulse buy on Amazon Prime day!  

 

I think what you re saying (besides the obvious that I could loose a few  ) is that a more powerful wheel won't have the same problems as this one. That makes sense to me I just wanted to be sure after watching @Marty Backe fall off his Gotway going up a hill. Maybe that one was steeper?  I want to make sure what I'm trying to do - commute from my house on a hill to work and back - is possible on ANY wheel before I go invest in a new wheel.

I'm hooked on this form of transport, it's fun, and for a fat slightly overweight beer lover, it's actually a bit of exercise, I'm hoping that I can find a way to make this work!

 

The amazon flash deal was an awesome one. $480 delivered! It is what prompted my first post on the forum and I almost pulled the trigger. I only didn't because of the Amazon review by The Mad Professor suggested other wheels which brought me here where I got the advice to skip it. That said, I still wish I had brought it just to have had a quality wheel to learn on before my V8 arrived.

If you got it for the $480 deal then you can likely eBay it for very little loss. That was my plan. Just don't burn it out before then by climbing a 25% grade on it! I think the S1 is rated to 20%.

[meepmeepmayer]

5 hours ago, applecran said:

Yeah hindsight... this was an impulse buy on Amazon Prime day! 

A lot of people make the "mistake" of starting with a Ninebot. But it isn't really a mistake. The Ninebot is a quality wheel for what it can do (slow riding) and with a good price. Would you have impulse bought a 1000$ wheel? Probably not. The Ninebots are a great gateway drug, once you've ridden one, the urge to get a better wheel will just get stronger, you'll see

For you, I recommend a 16S or a >1000Wh 18S, ACM, or msuper V3.

[WARPed1701D]

This page https://www.ewheels.com/electric-unicycle-ultimate_ewheel_comparison_ips_airwheel_ninebot_king_song_gotway/ (the graphic in particular) gives a good overview of different wheel specs and includes rated hill gradients. As already mentioned by @meepmeepmayer the KS 16S is really the starting point for your peak gradient but you are talking big money compared to what you paid for the S1 during the Amazon deal. It is a shame the V8 is no longer easily available as a slightly cheaper option for you. It wouldn't have been the best option for your situation but certainly better than the S1 and likely able to handle your weight and the peak gradient OK for a short period.

[meepmeepmayer]

@applecran A little explanation about wheels and inclines:

• These "rated for x%" numbers might as well be made up and mean nothing.
• What matters is the weight (EUC+rider). Lifting this weight is the decisive power requirement compared to flat terrain. Double that weight, you get half the incline percentage for the same power requirement. For example, assuming a 60 kg rider and a 80 kg rider plus a 15kg wheel, 20% incline for the 60kg rider is "the same" as 15% incline for the 80 kg rider [ (15+60)/(15+80)*20% = 15,8% ]. That's where numbers like "25% incline" come from, 50 kg light Chinese test riders.
• Super short inclines, even steep ones, are totally fine as long as your wheel can do them at all without breaking (like blowing a mosfet) or giving up. 25%, 45%, if it works it works.
• Long inclines are the tricky ones. They will (depending highly on your weight) require high currents. While the batteries (at least big ones) can provide this, the motor cables of basically all wheels aren't rated for these currents and are too thin (because they must fit through the thin axles). From Gotway wheels (ACM specifically, but msuper V3 has the exact same motor), we know that we can more or less reliably melt the cable isolation from the high temperatures (due to these currrents) which will short and destroy the board + motor and crash you. On extreme hills, mind you, but it's reproducible.
  See for example here: It's very hard to give numbers, but for me (80kg) on anything >10% incline I make regular breaks every few minutes (this is a very conservative experience value). I fried my ACM by going for >5 minutes (closer to 10) on a much steeper hill (not sure exactly what %). So a few minutes should be ok, but that is with my weight. You are 95kg so what is 10% for me is 9% for you, and 15% for me is 13% for you, etc.
  About other manufacturers, nobody really tested their wheels on long steep inclines (which create these currents), especially the new ones that are close in power to the Gotways (1200W 16S, 1500W 18S Kingsongs vs 1500W Gotways), but in theory they should have the same problem. Some might for some reason warn you (the Gotway Monster overheated on the same hill the ACM died, and was fine), some might work better for hills (Kingsongs, probably), but we simply have no real experience values because the only way to test what is too much for any wheel is to break it
  I don't want to scare you away. But long (more than just a few hundred meters), steep (>10%, or maybe >15%) inclines are really the high-demand situation that show us the limits of current wheels (no redundancy, so if some part breaks you crash; no guaranteed warnings for any kind of situation before something happens).
  This is all very conservative. In the end, the only way to test if a wheel can do something is to try it. Lots of people have used wheels for extensive mountain rides, but that just means they have their experience values what works. You need to build and have your own.
  I just want to mention, there is no wheel yet that would allow you to do a no-second-thoughts mountain ride on arbitrary inclines (such a wheel would either warn you of too high demand, or simply stop going, but NOT possibly blow a fuse or break or stop working in another way, guaranteed). That's my perspective, I got my EUC specifically with the idea of doing mountains. You need to be a little careful with those.
  The ride you mentioned, and if a Ninebot can do it, pretty sure you will NOT have these problems with a better wheel (the demands aren't high or long enough for that). So don't be scared away - just be aware Get a better wheel if you like, and enjoy! and wear protection

[WARPed1701D]

What an awesome post @meepmeepmayer.

For reference, reading the Inmotion manual for my V8 they do actually provide some test metadata pertaining to how they derived their range/hill angle/speed figures. Specifically to this discussion they used a 70kg person for the max hill angle spec. This is, to some degree, irrelevant as Inmotion is now basically a dead company in the US (you are in the US right?) but I imagine other manufacturers probably use a similar test scenario and so at 210lb you should lower the figures that you will see compared to what they quote. Of course as @meepmeepmayer mentions, they don't say how long you can maintain this level of climb angle for before something pops. We are their crash test dummies. Dummies being the most appropriate word there.

On 7/22/2017 at 1:10 PM, WARPed1701D said:

Digging up an old thread but there was some discussion above about how attainable the manufacturers specified range really was and I have read people saying in other threads that wheel ranges/speeds etc must be measured using trained baby monkeys going downhill in a stiff breeze. 

Well I finally read the manual today, especially the specifications.

Inmotion lists the range as 45-50km, max speed as 30kph and climb angle as 25 degrees. These were tested in the following conditions:
Terrain: Level road (except climb angle)
Rider Weight: 70kg
Ambient temperature: 25C

I'm lighter than the rider weight. I live in a near flat area and environmental temps are consistently between 25C and 35C so it will interesting to see if I get close to their their specs.

 

[meepmeepmayer]

@WARPed1701D Thanks!

Didn't know Inmotion had such a good manual. Sometimes we're lucky to get a non-Chinese text that could technically be called a manual with our wheels, so this is a surprise.

12 minutes ago, WARPed1701D said:

We are their crash test dummies. Dummies being the most appropriate work there.

 True.

To relativize the possible alarm here, from experience wheels are really safe and it takes a lot to crash or break one. Except for extreme hills (as defined by "Whoops that was too much, ouch my hands/knees, now I have to carry the thing down") or hardware failures (or people disabling alarms and going too fast), nothing ever happens and people ride wheels and enjoy.

[steve454]

21 hours ago, applecran said:

Good news is it seems it won't charge until the unit cools sufficiently.

I did not know that, but that is good news.  You should always let batteries cool down to room temperature before recharging.  They need to stabilize before going back up in charge, or it stresses the batteries too much.  This makes me think the Ninebot has some pretty good design for safety and longevity.  Good also that you turned it off for a time to let it cool down.