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#11
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Tomorrow's Bicycle Drive?
On Monday, June 3, 2019 at 12:07:53 AM UTC+1, AMuzi wrote:
On 6/2/2019 5:47 PM, John B. Slocomb wrote: On Sun, 2 Jun 2019 05:36:35 -0700 (PDT), Sir Ridesalot But HOW DO YOU SHIFT? Is it a lever, a grip shifter? What? The first reference I gave said that the "drive shaft" contained a remote receiver device which allowed shifting without wires or cable. No reference seems to have been given regarding the actual shift button, lever, whatever. Don't know but any of a dozen setups would work fine for that. Those of a certain age are thinking something like an electric solenoid overdrive switch: https://www.hemmings.com/blog/articl...ive-solenoids/ Charles Atlas strikes again. In our brave new world a wireless control stepper motor in side the chainstay with a handlebar up-down switch probably. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 The electronic switching is the least contentious part of this concept. Shimano has had a fully automatic switching system on sale since 1996, working on 3-speed and 8-speed Nexus hub gearboxes, and for all I know on their Alfine 11-speed as well. It has been supplied to European OEMs for umpteen years, and in the States at least to Trek for a bike they may have called Lime. The managing director of an upmarket Gazelle subsidiary, Kogo-Miyata, forecast that it was the wave of the future and in a few years all bikes would shift their gears electronically and automatically. Gazelle's own bike with the electronic automatic Nexus box was called the Saphir. The public didn't care; they didn't find shifting hub gearboxes a bother. You can see the system on my (European, designed by their Benelux operation) Trek in the photo-essay at http://coolmainpress.com/BICYCLINGsmover.html which shows how small the mechanical part of the change mechanism can be -- its a grey box on the rear hub. This particular electronic control system is cabled but there is no problem making it radio-controlled, or controlled by your phone via Bluetooth or Wi-Fi. And here is a two-part photo-report of a journey on that bike showing the control centre http://coolmainpress.com/BICYCLEKilmacsimon1.html http://coolmainpress.com/BICYCLEKilmacsimon2.html No batteries required: the front dynohub powered everything; what Shimano describes as a "battery" in the spec is a capacitor to power the system from the get-go when the bike has been standing. So much for the electronics. That Shimano made it work on the logical rotary motion of a hub gearbox change doesn't mean that it would work equally well on that monstrosity we're being shown, where there are four functions all in different directions to be achieved. First, the thing must somehow be clutched to disengage the gear on the shaft from the "cluster". Second and third, the motor must move the shaft backwards and forwards. Fourth, the clutch, however accomplished, must be thrown the other way. That doesn't sound like a small, tidy, stepper motor, singular, to me. I reckon that's two stepper motors, and not tiny ones either. Compare moving a metal shaft to handle 200W+ backwards and forwards to rotating a short, much thinner shaft that has an automatic clutch on it, as in a hub gearbox: we're clearly talking about two different levels of force. I conclude that those people have a concept and maybe some answers. But if they have all the answers, why not show us a working model? All of this is aside from the problem that a straight chainline to a quality hub gearbox inside a chain cover or a clean, well-adjusted derailleur setup is already so efficient that any marginal efficiency improvement they can claim will be imperceptible if actually delivered -- which I don't see either. Two sets of gears turning at right angles are never, ever likely to be as efficient as proven existing systems. This is an answer to a question that no one asked. I looked into those original Danish shaft drive bikes from Biomega a few years ago and forecast they would be off the market as soon as the fashion victims discovered they were nothing but trouble. Last year or the year before I tried to find one secondhand -- surely if they worked, there should be one for sale somewhere in Europe; none were. Andre Jute Let someone else take one for the team and spend his money on this bright idea |
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#12
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Tomorrow's Bicycle Drive?
On Sunday, June 2, 2019 at 4:42:04 AM UTC-7, Sir Ridesalot wrote:
On Sunday, June 2, 2019 at 5:49:03 AM UTC-4, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. -- Cheers, John B. Seems to be a concept bicycle not an actual bicycle. I'd like to see how the bicyclist initiates a shift. I'd also like to see it in actual use. I wonder what the cost will be? Cheers The problem is that it requires a specially constructed frame. |
#13
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Tomorrow's Bicycle Drive?
On Sunday, June 2, 2019 at 5:36:38 AM UTC-7, Sir Ridesalot wrote:
On Sunday, June 2, 2019 at 8:18:56 AM UTC-4, John B. Slocomb wrote: On Sun, 2 Jun 2019 04:42:01 -0700 (PDT), Sir Ridesalot wrote: On Sunday, June 2, 2019 at 5:49:03 AM UTC-4, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. -- Cheers, John B. Seems to be a concept bicycle not an actual bicycle. I'd like to see how the bicyclist initiates a shift. I'd also like to see it in actual use. I wonder what the cost will be? Cheers In the latter part of the narration he explains the shift. It is a bit complex as it apparently uses different "Paths" on the "cassette" depending on the speed of rotation. see https://www.youtube.com/watch?v=UFAQ6CzNm7s for a repeat of the above reference or google on "CeramicSpeed Driven chainless drivetrain" for about 11,000 hits. Apparently they have built at least one complete bike as one of the sites has a picture of someone riding one https://hiconsumption.com/2018/07/ce...ss-drivetrain/ In reading the fantastic claims for reduced friction one should remember that a chain drive may well have as high as 98% efficiency. https://www.cyclingpowerlab.com/Driv...fficiency.aspx So essentially the Ceramic system may provide 1% greater efficiency than a well functioning conventional system. -- Cheers, John B. But HOW DO YOU SHIFT? Is it a lever, a grip shifter? What? Cheers The mechanism is an electronic solenoid inside of the drive shaft. It would be simple and reliable. I like the idea but I don't think that we'll ever see them. |
#14
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Tomorrow's Bicycle Drive?
On Sunday, June 2, 2019 at 9:40:05 AM UTC-7, AMuzi wrote:
On 6/2/2019 11:18 AM, Frank Krygowski wrote: On 6/2/2019 5:48 AM, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. I estimate that a New! Innovative! Revolutionary! Better! bicycle transmission has been invented every two years or so. I would expect a hypoid gear set in an oil bath to be relatively efficient compared to a chain. Any ME comments on an open crown & pinion set? -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 The problems with all of these "concept" drives is that they place an offset force pushing the gears apart verses that chain drive where all of the off-setting forces are in a more or less straight line with the frame. |
#15
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Tomorrow's Bicycle Drive?
On Wed, 5 Jun 2019 15:39:28 -0700 (PDT), Tom Kunich
wrote: On Sunday, June 2, 2019 at 9:40:05 AM UTC-7, AMuzi wrote: On 6/2/2019 11:18 AM, Frank Krygowski wrote: On 6/2/2019 5:48 AM, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. I estimate that a New! Innovative! Revolutionary! Better! bicycle transmission has been invented every two years or so. I would expect a hypoid gear set in an oil bath to be relatively efficient compared to a chain. Any ME comments on an open crown & pinion set? -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 The problems with all of these "concept" drives is that they place an offset force pushing the gears apart verses that chain drive where all of the off-setting forces are in a more or less straight line with the frame. Sort of like a BMW motorcycle that has used a similar shaft drive for the past 90 years? -- cheers, John B. |
#16
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Tomorrow's Bicycle Drive?
On 6/5/2019 6:36 PM, John B. wrote:
On Wed, 5 Jun 2019 15:39:28 -0700 (PDT), Tom Kunich wrote: On Sunday, June 2, 2019 at 9:40:05 AM UTC-7, AMuzi wrote: On 6/2/2019 11:18 AM, Frank Krygowski wrote: On 6/2/2019 5:48 AM, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. I estimate that a New! Innovative! Revolutionary! Better! bicycle transmission has been invented every two years or so. I would expect a hypoid gear set in an oil bath to be relatively efficient compared to a chain. Any ME comments on an open crown & pinion set? The problems with all of these "concept" drives is that they place an offset force pushing the gears apart verses that chain drive where all of the off-setting forces are in a more or less straight line with the frame. Sort of like a BMW motorcycle that has used a similar shaft drive for the past 90 years? BMW shaft drive? Maybe copied the 1901 FN: https://cdn.motor1.com/images/mgl/XR...haft-drive.jpg Seriously, motorcycles with shaft drive have enclosed precision bevel gears unlike the open crown and pinion shown. Well made and durable shaft drives were relatively popular around 1900. I've ridden one, the 1910 Columbia, a truly pleasant ride (although fixed gear unlike the concept bike). -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
#17
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Tomorrow's Bicycle Drive?
On Sun, 02 Jun 2019 16:48:57 +0700, John B. Slocomb wrote:
See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. Just a rehash of old ideas. The same reasons for the failure of shaft drives will see it fail again. Of couses, as ther is electronics involved, that will introduce another pile of reasons for it to fail. |
#18
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Tomorrow's Bicycle Drive?
On Sunday, June 2, 2019 at 5:49:03 AM UTC-4, John B. Slocomb wrote:
See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. -- Cheers, John B. I can just imaging what road grit when it rains will do to those exposed bearings and interface. Can we say RAPID wear? Cheers |
#19
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Tomorrow's Bicycle Drive?
On Thursday, June 6, 2019 at 9:11:17 AM UTC-7, Sir Ridesalot wrote:
On Sunday, June 2, 2019 at 5:49:03 AM UTC-4, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. -- Cheers, John B. I can just imaging what road grit when it rains will do to those exposed bearings and interface. Can we say RAPID wear? Cheers What exposed bearings? They are sealed ceramic bearings. But again, the frame must be custom built for it. So there's no way it would ever make it on the market. |
#20
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Tomorrow's Bicycle Drive?
On Thu, 6 Jun 2019 14:01:28 -0000 (UTC), news18
wrote: On Sun, 02 Jun 2019 16:48:57 +0700, John B. Slocomb wrote: See https://www.youtube.com/watch?v=-9gQ1KRhesM In the narration he mentions that a 24 speed gear set, or even more, would be perfectly feasible. No wires, no cables, either. Just a rehash of old ideas. The same reasons for the failure of shaft drives will see it fail again. Of couses, as ther is electronics involved, that will introduce another pile of reasons for it to fail. Why did shaft drives fail? Complexities? And so we have hydraulic brake systems as opposed to simply mechanical brakes, electronic shifters as opposed to simple mechanical systems, and so on. -- cheers, John B. |
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