That Guy Posted February 4, 2022 Share Posted February 4, 2022 8 hours ago, UniVehje said: KS had similar issue with early 16X units as well. Should be just a software issue as it was fixed quickly back then. Are high speed oscillations and high speed wobbles the same thing? If so, I don't understand how the motor controller can contribute them, because I thought they depend on how high the centre of gravity is and how many parts are moving (so that they could induce vibration that can resonate with the rest of the construction)? 2 Quote Link to comment Share on other sites More sharing options...
Popular Post 5Cauac Posted February 5, 2022 Popular Post Share Posted February 5, 2022 41 minutes ago, That Guy said: Are high speed oscillations and high speed wobbles the same thing? I believe the oscillations in question is a front to back vibration not a side to side (wobble). Sorta like the feeling of the magnets skipping is my guess as I've never experienced said oscillations. 5 1 1 Quote Link to comment Share on other sites More sharing options...
rolis Posted February 5, 2022 Share Posted February 5, 2022 8 hours ago, 5Cauac said: I believe the oscillations in question is a front to back vibration not a side to side (wobble). Sorta like the feeling of the magnets skipping is my guess as I've never experienced said oscillations. Kuji has experienced oscillations with the 16x as you can see here: but this was be fixed with a firmware update. I expect the s20 to be the same 2 Quote Link to comment Share on other sites More sharing options...
UniVehje Posted February 5, 2022 Share Posted February 5, 2022 11 hours ago, That Guy said: Are high speed oscillations and high speed wobbles the same thing? If so, I don't understand how the motor controller can contribute them, because I thought they depend on how high the centre of gravity is and how many parts are moving (so that they could induce vibration that can resonate with the rest of the construction)? These oscillations are different, as mentioned in the posts above. Wobbles are almost always user error although quite often people blame wheels for them. The fact is, experienced people don't get them and reviewers are usually new to the wheels they test. Only in very rare cases wobbles can be caused by the wheel. E.g. tire can be seated improperly. 2 1 Quote Link to comment Share on other sites More sharing options...
Mike Sacristan Posted February 5, 2022 Share Posted February 5, 2022 I tried the early 16x pre 1.05 FW and it has front back oscillation at over 40kmh. Very exciting stuff. It is a very quick back and forth movement... perhaps 2mm back and forth and increases the faster you go. 1 2 Quote Link to comment Share on other sites More sharing options...
The Brahan Seer Posted February 5, 2022 Share Posted February 5, 2022 There might be a natural or resonance frequency thats causing the vibrations. This can occur when it hits the frequency the material/design start to vibrate in sympathy with itself. Usual symptom of this would be fine at low speed, hits x speed and starts to vibrate and then fine over this speed again. Quote Link to comment Share on other sites More sharing options...
Beachboy Posted February 6, 2022 Share Posted February 6, 2022 19 hours ago, rolis said: Kuji has experienced oscillations with the 16x as you can see here: but this was be fixed with a firmware update. I expect the s20 to be the same Speaking of kuji, I’m sure he received his S20 already but no vids came out..where is this guy.. Quote Link to comment Share on other sites More sharing options...
That Guy Posted February 6, 2022 Share Posted February 6, 2022 Kuji has been quiet lately, not just about S20. Also, I think Kuji is an urban rider rather than off-roader. Not sure S20 would be his cup of tea. (It's just my stereotype forming based on all these jumping videos of S20 and zero urban high speed riding.) 1 Quote Link to comment Share on other sites More sharing options...
Mango Posted February 6, 2022 Author Share Posted February 6, 2022 I read somewhere either here or elsewhere that Kuji cut out on the S20. It’s rehashed old news but bringing it up again if anyone here hasn’t known about it. He had previously said he was going to do a V11 vs S18 comparison video but that one never came out… likely he may have experienced cutouts on one or both units. Quote Link to comment Share on other sites More sharing options...
Popular Post fbhb Posted February 6, 2022 Popular Post Share Posted February 6, 2022 3 hours ago, Mango said: I read somewhere either here or elsewhere that Kuji cut out on the S20. I thought the story about Kuji cutting out was in reference to the Commander and definitely Not the S20 IIRC? 5 Quote Link to comment Share on other sites More sharing options...
Mango Posted February 6, 2022 Author Share Posted February 6, 2022 (edited) No, he cut out on both machines. (Commander and S20) Edited February 6, 2022 by Mango Quote Link to comment Share on other sites More sharing options...
Popular Post Rolzi Posted February 6, 2022 Popular Post Share Posted February 6, 2022 5 Quote Link to comment Share on other sites More sharing options...
Paradox Posted February 6, 2022 Share Posted February 6, 2022 17 minutes ago, Rolzi said: Why do you think it's beeping? Quote Link to comment Share on other sites More sharing options...
Popular Post Tawpie Posted February 6, 2022 Popular Post Share Posted February 6, 2022 (edited) 30 minutes ago, Paradox said: Why do you think it's beeping? I think they have the safeties turned off (it went to 81 kph, which I don't think will be allowed in consumer units). Maybe it's a warning about that. The best news is that they can replicate the oscillation on the tilt rack—and that means they will be able to fix it! Edited February 6, 2022 by Tawpie 6 Quote Link to comment Share on other sites More sharing options...
Rollin-on-1 Posted February 6, 2022 Share Posted February 6, 2022 3 hours ago, Tawpie said: I think they have the safeties turned off (it went to 81 kph, which I don't think will be allowed in consumer units). Maybe it's a warning about that. The best news is that they can replicate the oscillation on the tilt rack—and that means they will be able to fix it! The EUCO demo spun 101 kph when it was fully charged. 1 Quote Link to comment Share on other sites More sharing options...
Jon Stern Posted February 6, 2022 Share Posted February 6, 2022 7 minutes ago, Rollin-on-1 said: The EUCO demo spun 101 kph when it was fully charged. Not the same test. That was without the weight of a 70lb wheel. 1 Quote Link to comment Share on other sites More sharing options...
supercurio Posted February 6, 2022 Share Posted February 6, 2022 6 hours ago, Tawpie said: I think they have the safeties turned off (it went to 81 kph, which I don't think will be allowed in consumer units). Maybe it's a warning about that. The best news is that they can replicate the oscillation on the tilt rack—and that means they will be able to fix it! Spot on! Glad they have the rig to run this kind of test, and oh wow this needs a lot or tuning. 3 Quote Link to comment Share on other sites More sharing options...
Rolzi Posted February 7, 2022 Share Posted February 7, 2022 24 minutes ago, supercurio said: Spot on! Glad they have the rig to run this kind of test, and oh wow this needs a lot or tuning. I want to make sure you all are seeing what iam seeing. The tester is the one repeatedly pushing the wheel forward while trying to induce the oscillations on this video. You can go frame by frame and you see his forearm move first when hes pushing the wheel. I think if it was the wheel that is jolting the dynamics of the movements would be different. I don´t see any of the kind of oscillation that we see in the previous speed test videos. 3 Quote Link to comment Share on other sites More sharing options...
Tawpie Posted February 7, 2022 Share Posted February 7, 2022 (edited) It's difficult to know for me because I don't know how the tilt rack works, and I haven't felt the oscillations... but my guess is that the tester has to push the wheel forward and keep pushing to keep it going. It looks to me like his arm is jerking as the wheel suddenly changes something (power almost certainly), and the jerk doesn't look all that different from the rider's sudden knee bends. Maybe 'oscillations' isn't the best description of what the rider experienced? The movements weren't exactly smooth, 'jerky' was the impression I got. It could be describing "oscillating between expected power and not-expected power" since it jerked, then seemed to recover, then jerked again and repeated. It might feel like pedal-dip, recover, pedal-dip, recover and not quite as jerky as it looks (knees are smoothing things out). Either way, what's seen in both videos needs attention... it ain't quite all the way right just yet. Edited February 7, 2022 by Tawpie 2 Quote Link to comment Share on other sites More sharing options...
mrelwood Posted February 7, 2022 Share Posted February 7, 2022 7 hours ago, Jon Stern said: Not the same test. That was without the weight of a 70lb wheel. The weight of the wheel isn’t slowing down the speed in a test like that. After all the weight is stationary. It only creates a little friction at the tire, but unless the rig has a planned resistance or weight to it’s rollers, the wheel will definitely be able to get pretty close to it’s lift speed. For example a 104km/h free spinning Sherman can be ridden up to 85km/h, where the air drag and the power requirements of an accelerating adult both create a huge power demand. Without a top speed tilt-back the S20 should get to comparable riding speeds. Maybe the operator tries to keep the speed at around the planned maximum of 70km/h. 1 Quote Link to comment Share on other sites More sharing options...
Chriull Posted February 7, 2022 Share Posted February 7, 2022 14 hours ago, Tawpie said: I think they have the safeties turned off (it went to 81 kph, which I don't think will be allowed in consumer units). Maybe it's a warning about that. On the test rig the wheel can accelerate above tiltback speed without need to turn safeties off. It should just "auto accelerate" till lift cut off speed is reachec as the pedal cannot tilt back - so the operator seemed to brake again above ?70 km/h? Irl riding faster as tiltback sperd is possible if one can (acrobatically) balance on the tilted pedals... 14 hours ago, Tawpie said: The best news is that they can replicate the oscillation on the tilt rack—and that means they will be able to fix it! 7 hours ago, Rolzi said: The tester is the one repeatedly pushing the wheel forward while trying to induce the oscillations on this video. You can go frame by frame and you see his forearm move first when hes pushing the wheel. I think if it was the wheel that is jolting the dynamics of the movements would be different. I don´t see any of the kind of oscillation that we see in the previous speed test videos. Oscillations are likely different on the test rig compared to real life, as the rider trying to keep standing on the wheel could "get in resonance with the wheel". But such oscillations are very likely overshoots of the control algorithm normally triggered by such pushing (load/burden changes). They should see from logging the wheel data/test rig data each not so nice behaviour of the algorithm without the euc oscilating wildly on the rig. 3 Quote Link to comment Share on other sites More sharing options...
supercurio Posted February 7, 2022 Share Posted February 7, 2022 18 hours ago, Mango said: No, he cut out on both machines. (Commander and S20) Could you link or mention the source please? 🙏 2 Quote Link to comment Share on other sites More sharing options...
Rolzi Posted February 7, 2022 Share Posted February 7, 2022 (edited) 10 hours ago, Tawpie said: It's difficult to know for me because I don't know how the tilt rack works, and I haven't felt the oscillations... but my guess is that the tester has to push the wheel forward and keep pushing to keep it going. It looks to me like his arm is jerking as the wheel suddenly changes something (power almost certainly), and the jerk doesn't look all that different from the rider's sudden knee bends. Maybe 'oscillations' isn't the best description of what the rider experienced? The movements weren't exactly smooth, 'jerky' was the impression I got. It could be describing "oscillating between expected power and not-expected power" since it jerked, then seemed to recover, then jerked again and repeated. It might feel like pedal-dip, recover, pedal-dip, recover and not quite as jerky as it looks (knees are smoothing things out). Either way, what's seen in both videos needs attention... it ain't quite all the way right just yet. Here I disagree completely. Best example i can find is at 35 second mark where you can clearly see the sleeve of his shirt move before the force is translated from his arm to the wheel. It matters little since it seems the problems is being taken care of anyway. (I don´t see any problem with the wheel in this video). Edit: Other things that come to mind: Why would the wheel make the sound of speeding up in this video when its "jolting". Wouldn´t the force actually translate backwards if it was the wheel that was suddenly accelerating? Edited February 7, 2022 by Rolzi 1 Quote Link to comment Share on other sites More sharing options...
Rollin-on-1 Posted February 7, 2022 Share Posted February 7, 2022 15 minutes ago, Rolzi said: Here I disagree completely. Best example i can find is at 35 second mark where you can clearly see the sleeve of his shirt move before the force is translated from his arm to the wheel. It matters little since it seems the problems is being taken care of anyway. (I don´t see any problem with the wheel in this video). Do we know the date this video was recorded? According to EUCO, they have not discussed the oscillations with KS yet. What I saw indicated rhey would be contacting them today. (source: comment in an IG post iirc). Quote Link to comment Share on other sites More sharing options...
Rollin-on-1 Posted February 7, 2022 Share Posted February 7, 2022 7 hours ago, mrelwood said: The weight of the wheel isn’t slowing down the speed in a test like that. After all the weight is stationary. It only creates a little friction at the tire, but unless the rig has a planned resistance or weight to it’s rollers, the wheel will definitely be able to get pretty close to it’s lift speed. For example a 104km/h free spinning Sherman can be ridden up to 85km/h, where the air drag and the power requirements of an accelerating adult both create a huge power demand. Without a top speed tilt-back the S20 should get to comparable riding speeds. Maybe the operator tries to keep the speed at around the planned maximum of 70km/h. This is the point I was trying to make earlier. It may be possible that they have a friction brake of some sort that increases to resistance as the wheel increases speed to simulate the various loads that limit top speed during riding conditions. The fact that it doesn't cutoff could then be an indicator that an 80 kph may be a realistic safe speed for the wheel. We really don't have enough info at this point to make any real assumptions. Hopefully we will get that info soon. 1 Quote Link to comment Share on other sites More sharing options...
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