THA Posted February 6, 2016 Share Posted February 6, 2016 @Cloud I think You'll faceplant on downhill too on the theoretical top speed since it depends on voltage. Of course voltage depends on load (current) too and current determinesthe torque so this test doesn't match any real life situation on flat. Except that Lhotz tilt back 30kph and my ineptitude (I don'tknow if this in any correct word,had to take google translate to help) determines my real life top speed Link to comment Share on other sites More sharing options...
Cloud Posted February 6, 2016 Share Posted February 6, 2016 1 minute ago, THA said: @Cloud I think You'll faceplant on downhill too on the theoretical top speed since it depends on voltage. Of course voltage depends on load (current) too and current determinesthe torque so this test doesn't match any real life situation on flat. Except that Lhotz tilt back 30kph and my ineptitude (I don'tknow if this in any correct word,had to take google translate to help) determines my real life top speed Yes, unless a wheel also cuts out because of the high soeed alone, the load should have a big effect. i am just know sure what the test shows, except how the wheel behaves at top speed in terms of stability, high speed beeps, etc abd what the max attainable top speed is due to tiltback. i would think that to test the real life max speed, there should be a different device that doesnt do the work for you. More like the one they use to get car inspection - car wheel rotates 2 more wheel cylinders set in the floor. Maybe one could make it adjustable to set a desired load on the cylinders to imitate the real life load. This way, one wouldnt need to even ride the wheel. The load could be set accordingly. Alternatively ( or in combination) a weight could be applied / placed on the wheel to imitate the load from the increased friction from the riders weight. Link to comment Share on other sites More sharing options...
THA Posted February 6, 2016 Share Posted February 6, 2016 12 minutes ago, Cloud said: Yes, unless a wheel also cuts out because of the high soeed alone... i would think that to test the real life max speed, there should be a different device that doesnt do the work for you. Because I (and probably many others) am able to cruise w/ tilt back downhill easier, I would like to know downhill safety limits of my wheel. When speed exceeds wheels theoretical tops speed, control electronics can't keep it balanced anymore because there is no more voltage margine left to increase wheels speed, it's physics. I hope my wheel tips my heels to ground long before I reach that max speed... I wouldn't like to faceplant to asphalt, on a hot summer day, returning from beach, wearing a swimming suit and towel only... Link to comment Share on other sites More sharing options...
Pasi Posted February 6, 2016 Author Share Posted February 6, 2016 @Cloud , @THA my old school treadmill (no motor or electronic) is mechanical and the wheel must do all the work to get rubber carpet to roll over. I think it must do a lot of work. Link to comment Share on other sites More sharing options...
Pasi Posted February 7, 2016 Author Share Posted February 7, 2016 @Lizzard mine weight 13.00kg with trolley. This is my treadmill, I got nice video but I must ask tomorrow somebody how to load it. And video has been taken with same phone I have the Gotway App, so I could not show the speed. Next time I take tablet with App so the speed is there too. But on that video I can see/hear all beeps and how strongly it tiltback and finally device get off. And I did not hurt at all. Link to comment Share on other sites More sharing options...
Frankman Posted February 7, 2016 Share Posted February 7, 2016 @Pasi This is a great idea to test our EUC at maximum speed without a faceplant risk. Good job ! Link to comment Share on other sites More sharing options...
Nevin@Tec-toyz.com Posted February 8, 2016 Share Posted February 8, 2016 6 hours ago, Pasi said: @Lizzard mine weight 13.00kg with trolley. This is my treadmill, I got nice video but I must ask tomorrow somebody how to load it. And video has been taken with same phone I have the Gotway App, so I could not show the speed. Next time I take tablet with App so the speed is there too. But on that video I can see/hear all beeps and how strongly it tiltback and finally device get off. And I did not hurt at all. Post some videos please! I'm sure we would all love to see how this turned out. Link to comment Share on other sites More sharing options...
Pasi Posted February 8, 2016 Author Share Posted February 8, 2016 Hi, my first video shared for ever (if it works): https://onedrive.live.com/redir?resid=42072C17518EFF45!462&authkey=!ANAm-bxK9f3SE90&ithint=video%2cmp4 Link to comment Share on other sites More sharing options...
THA Posted February 8, 2016 Share Posted February 8, 2016 Ouh yeah, so safe compared to gym treadmill test! Quite a hard tilt back on MCM4 too, wouldn't expect accidental speeding Link to comment Share on other sites More sharing options...
Nevin@Tec-toyz.com Posted February 9, 2016 Share Posted February 9, 2016 On February 2, 2016 at 2:29 AM, Lizzard said: Could you please, weigh it? Mine MCM4 520Wh - 14.00 kg @Lizzard MCM4 340Wh weighs in at 12.45kg Link to comment Share on other sites More sharing options...
Nevin@Tec-toyz.com Posted February 12, 2016 Share Posted February 12, 2016 I see a couple issues. This needs to be done on a flat surface treadmill. Second, It should be a gradual acceleration, seems like your acceleration is a bit fast. maybe dues to treadmill speed you have it set to. I think a free spinning treadmill would probably work better like the treadmills they use to walk dogs. Maybe a tethering system to keep the wheel from becoming a flying object. lol, watching too many failed treadmill videos.... Link to comment Share on other sites More sharing options...
alexbot Posted February 28, 2016 Share Posted February 28, 2016 Any updates from mcm4 hs riders? Any faceplants or things I should look out for? Mine should be here soon. Link to comment Share on other sites More sharing options...
Pasi Posted March 4, 2016 Author Share Posted March 4, 2016 Here it is not good time to ride. Streets are covered with gravel against of slippery. We call it killer-gravel because it kills all the tires of bicycles. After few weeks they should take/clean it away. And it gets stuck badly between tyre and the shell. Link to comment Share on other sites More sharing options...
WakefulTraveller Posted April 2, 2016 Share Posted April 2, 2016 Would it be possible to grind / sand away more clearance for the tire? Would the difference between the 340 WH battery and the 520 WH battery on the HS model be worth the extra $130 if cost is a big concern? (35-38KM life)) 340WH, using 2900ma Panasonic PF 10A/P 32P (52-55KM life) 520WH, using 2200ma SONY 10A/P 64p Link to comment Share on other sites More sharing options...
Tomek Posted April 2, 2016 Share Posted April 2, 2016 31 minutes ago, WakefulTraveller said: Would it be possible to grind / sand away more clearance for the tire? not really, unless you want to ruin the smoked-transparent-plastic led-light cover. the main-shell plastic underneath it is already thinned down, so by removing it you'd only save 1mm. also, the clearance is quite small along the whole perimeter of the tire, not just on the edges (although there it's the smallest) 31 minutes ago, WakefulTraveller said: Would the difference between the 340 WH battery and the 520 WH battery on the HS model be worth the extra $130 if cost is a big concern? (35-38KM life)) 340WH, using 2900ma Panasonic PF 10A/P 32P (52-55KM life) 520WH, using 2200ma SONY 10A/P 64p I'd go for the 520Wh option, not for the capacity, but because it gives you double the max amperage = double effective peak power of the motor That said, it adds ~2kg to the weight of the wheel (that's why I ended up choosing to make my own batteries with high current drain cells) Link to comment Share on other sites More sharing options...
WakefulTraveller Posted April 3, 2016 Share Posted April 3, 2016 4 hours ago, Tomek said: I'd go for the 520Wh option, not for the capacity, but because it gives you double the max amperage = double effective peak power of the motor That said, it adds ~2kg to the weight of the wheel (that's why I ended up choosing to make my own batteries with high current drain cells) I did not realize that the 520WH battery would weigh that much more. What would the difference be in real life performance (besides longer peek performance)? Will the motor actually take advantage of extra amperage when the battery level is greater than say 50%? Will it be safer? I'm hoping that you can answer these perhaps hard to answer questions, or at least excuse my ignorance and dumb it down for me. I know next to nothing about electricity and batteries. Link to comment Share on other sites More sharing options...
Tomek Posted April 3, 2016 Share Posted April 3, 2016 6 hours ago, WakefulTraveller said: I did not realize that the 520WH battery would weigh that much more. perhaps a bit less, but 32 cells on their own weigh 1.5kg 6 hours ago, WakefulTraveller said: What would the difference be in real life performance (besides longer peek performance)? Will the motor actually take advantage of extra amperage when the battery level is greater than say 50%? Will it be safer? hard to be exact, i haven't seen any proper comparisons of different MCM4 battery models, @Jason McNeil had some insights regarding KS14c with different batteries, but not a solid test if I recall. to give you some insights though: how LiIon battery cells (and most other) work is they slowly drop their voltage when discharged. you shouldn't charge them above 4.2v and discharge under 2.7v because the cell will get damaged (and possibly catch fire). BMS board takes care that it doesn't happen. the state of battery charge % is typically measured by measuring the battery voltage. now, what does all this mean for eucs? first of all an almost empty battery delivers 35% less power to the motor than a full one because it has lower voltage. second of all, when a lot of current is drawn, the voltage of the battery additionally drops and the battery can overheat. (high-discharge cells have much less of this problem, but for those there seem to be supply chain problems in china and they're not standard in eucs.) the MCM4 has a motor rated for 800W, but it can easily have peak power drain that is much more than that (1500W or even above 2500W as some state). a fullycharged double pack (2*10A) can give you a max of 1340W, while two double packs 2700W. the almost empty double pack will only give you 860W, while two of them will give you 1720W. if the motor draws more than the battery allows, the voltage drops even further, the battery heats up, and you get even less juice out of it. so, with two double packs you take full advantage of the 800W motor, in the case of one double pack, not really. what does it mean in practice? if you just have one double pack it'll be easier to overlean, less dynamic acceleration, poor performance on a partially drained battery, and quicker practical battery drain than would seem from just comparing the Wh. Saying all this, it's of course partially speculative, I don't know how big the differences are in reality. hope someone with first hand experience with comparing both options can chime in. Link to comment Share on other sites More sharing options...
Dr Bob Posted April 3, 2016 Share Posted April 3, 2016 On 2/12/2016 at 6:36 AM, NevNutz said: I see a couple issues. This needs to be done on a flat surface treadmill. Second, It should be a gradual acceleration, seems like your acceleration is a bit fast. maybe dues to treadmill speed you have it set to. I think a free spinning treadmill would probably work better like the treadmills they use to walk dogs. Maybe a tethering system to keep the wheel from becoming a flying object. lol, watching too many failed treadmill videos.... Today my friend who tested my batteries and myself made a euc dyno from bicycle stationary trainer. they lock on the back wheel of bike and ride on the spot type. You can adjust load and it has tacho, odometer and speedometer on it. We changed the static magnetic resistance to electric, my friend not me and we made 2 brackets that swivel and attach to the footboards, brackets have speed turnbuckles to hold wheel in place firmly, also we added 4 roller blade wheels, 2 to support wheel with main roller and 1 on each side to keep it running straight, a must to get genuine figures from my many years dyno tuning motorcycles. So euc is held firmly by trainer, but you can tilt euc forward and backwards. This is much cheaper that treadmill as well as much safer as wheel can go no where. I will post some pic's of it over the next week and details on how to make the same. Cost for me to make was $45aus all up and about 50 minutes of my time. My friend who is RC expert is finding software so we can obtain data about hp, watts etc like a normal dyno, this I will also post with pic's and how to make when it is sorted. Link to comment Share on other sites More sharing options...
Jason McNeil Posted April 3, 2016 Share Posted April 3, 2016 5 hours ago, Tomek said: @Jason McNeil had some insights regarding KS14c with different batteries, but not a solid test if I recall. to give you some insights though: Yep, basically the standard 680Wh types that are used in KS (MG1) & GW (Panos PF) are pretty suboptimal by today's standards. The higher internal resistance causes the voltage to fall away under medium-high sustained loads. A secondary factor is that the IR seems to be correlated to the charging rates; because Wheels dump the excess energy back into the battery under braking, or descent situations, over time this is probably the single greatest contributing factor to premature battery pack death. Link to comment Share on other sites More sharing options...
WakefulTraveller Posted April 3, 2016 Share Posted April 3, 2016 16 minutes ago, Jason McNeil said: Yep, basically the standard 680Wh types that are used in KS (MG1) & GW (Panos PF) are pretty suboptimal by today's standards. The higher internal resistance causes the voltage to fall away under medium-high sustained loads. A secondary factor is that the IR seems to be correlated to the charging rates; because Wheels dump the excess energy back into the battery under braking, or descent situations, over time this is probably the single greatest contributing factor to premature battery pack death. So would the 2200 ma (mAH?) Sony battery be better than the 2900ma Panasonic battery because of the faster charge times when it comes to lower mAh batteries? Would this mean a longer expected life span of the Sony battery pack? I have trouble seeing it as worth it to get a custom battery pack for the MCM4. I imagine that with everything considered it would be notably more expensive and troublesome. Link to comment Share on other sites More sharing options...
Jason McNeil Posted April 3, 2016 Share Posted April 3, 2016 12 minutes ago, WakefulTraveller said: would the 2200 ma (mAH?) Sony battery be better than the 2900ma Panasonic battery because of the faster charge times when it comes to lower mAh batteries It's not the charge time in min/hrs that matter but the current (Amps) that's important. Beside our resident wizard @esaj, I'm not certain anyone has had success in building their own battery pack. It's quite an undertaking, probably better off sourcing from a distributor or manufacturer. Link to comment Share on other sites More sharing options...
US69 Posted April 3, 2016 Share Posted April 3, 2016 To both questions a big NO! :-) i have learned for me: it is cheaper to get a new Batterie pack After buying...then to buy a bigger batterie pack direct with The EU... but: this May be because i have a Real good Batterie/EUC distributor here in Germany.... Link to comment Share on other sites More sharing options...
WakefulTraveller Posted April 3, 2016 Share Posted April 3, 2016 So would it be a good idea to buy the version with either the 260WH or 340WH 32 cell battery pack on one side and then find someone that can put together another battery pack for the other side? Will two different battery packs side by side be compatible with each other? Link to comment Share on other sites More sharing options...
SlowMo Posted April 3, 2016 Share Posted April 3, 2016 5 minutes ago, WakefulTraveller said: So would it be a good idea to buy the version with either the 260WH or 340WH 32 cell battery pack on one side and then find someone that can put together another battery pack for the other side? Will two different battery packs side by side be compatible with each other? Why not buy the 680wh unit thereby avoiding any headache. Link to comment Share on other sites More sharing options...
WakefulTraveller Posted April 3, 2016 Share Posted April 3, 2016 7 minutes ago, SlowMo said: Why not buy the 680wh unit thereby avoiding any headache. I'm thinking that the 680wh is overkill, when the 520wh will be just as good (aside from the range) and plus it will take less time to charge. The reason that I'm considering a custom battery pack is save on cost, possibly to buy the battery pack at a later date, and to have more optimal batteries (rapid discharge / recharge?). Link to comment Share on other sites More sharing options...
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