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Racing innovation?
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#2
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Racing innovation?
"DirtRoadie" wrote in message ... http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. |
#3
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Racing innovation?
In article ,
wrote: "DirtRoadie" wrote in message ... http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. One of the fundamental aspects of conspiracy theories is that the believed validity is directly proportional to the effort that goes into creating the story. Sasquatch, JFK, alien abduction, the Tea Party, etc. are all good examples. |
#4
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Racing innovation?
On May 30, 1:47*pm, wrote:
"DirtRoadie" wrote in message ...http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR |
#5
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Racing innovation?
On 31 May, 07:03, DirtRoadie wrote:
On May 30, 1:47*pm, wrote: "DirtRoadie" wrote in message ....http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything.. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if *a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR If you look at the first clip his speed increases from four secound between posts to three seconds, now look carefully at his front wheel. It is swaying from side to side due to high pedalling effort despite steering input to keep the bike straight. There is no stroll in the park here. Motors have advanced somewhat in the last twenty years and compact arrangments are possible. I dont know if these same compact motors have the efficiency required to utilise small battery packs that would fit around the frame. It seems highly unlikely that sufficient strength of the drive to the axle (within a normal size bottom bracket) be obtained for usable levels of assisted torque. I am open to be proved wrong on both these items. |
#6
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Racing innovation?
thirty-six wrote:
On 31 May, 07:03, DirtRoadie wrote: On May 30, 1:47 pm, wrote: "DirtRoadie" wrote in message ...http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR If you look at the first clip his speed increases from four secound between posts to three seconds, now look carefully at his front wheel. It is swaying from side to side due to high pedalling effort despite steering input to keep the bike straight. There is no stroll in the park here. Motors have advanced somewhat in the last twenty years and compact arrangments are possible. I dont know if these same compact motors have the efficiency required to utilise small battery packs that would fit around the frame. It seems highly unlikely that sufficient strength of the drive to the axle (within a normal size bottom bracket) be obtained for usable levels of assisted torque. I am open to be proved wrong on both these items. If he's in the running at all, 100 extra watts for 15 minutes will make plenty of difference, is not technically difficult to accomplish, and is not overly burdensome to carry the entire race distance. Lithium polymer cells sustaining 4C discharge rate and hobby model airplane or car motors are cheap and ubiquitous. 12V 2400 mAh packs are small and light. You can do it for $200 at hobby shop rates, for less than 1 lb total mass. I'm not saying he did so; just pointing out the feasibility. |
#7
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Racing innovation?
On May 31, 1:59*pm, "MikeWhy" wrote:
thirty-six wrote: On 31 May, 07:03, DirtRoadie wrote: On May 30, 1:47 pm, wrote: "DirtRoadie" wrote in message ....http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR If you look at the first clip his speed increases from four secound between posts to three seconds, now look carefully at his front wheel. *It is swaying from side to side due to high pedalling effort despite steering input to keep the bike straight. *There is no stroll in the park here. Motors have advanced somewhat in the last twenty years and compact arrangments are possible. *I dont know if these same compact motors have the efficiency required to utilise small battery packs that would fit around the frame. *It seems highly unlikely that sufficient strength of the drive to the axle (within a normal size bottom bracket) be obtained for usable levels of assisted torque. *I am open to be proved wrong on both these items. If he's in the running at all, 100 extra watts for 15 minutes will make plenty of difference, is not technically difficult to accomplish, and is not overly burdensome to carry the entire race distance. Lithium polymer cells sustaining 4C discharge rate and hobby model airplane or car motors are cheap and ubiquitous. 12V 2400 mAh packs are small and light. You can do it for $200 at hobby shop rates, for less than 1 lb total mass. I'm not saying he did so; just pointing out the feasibility. http://www.gruberassist.com/ "At an optimal pedal frequency of approx. 60 pedal revolutions per minute, the bicycle drive provides the rear wheel with up to 100 watts." I agree that it sure seems as if those little gears would have to handle a lot of torque - the same kind of forces on the BB spindle as those generated by a rider putting out 100 watts @ 60 rpm. But wait, there's mo http://www.youtube.com/watch?v=wGYqKBUEelw http://www.youtube.com/watch?v=jmPUze3WBTw http://www.youtube.com/watch?v=nWtnfgDbBd4& DR |
#8
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Racing innovation?
On 31 May, 20:59, "MikeWhy" wrote:
thirty-six wrote: On 31 May, 07:03, DirtRoadie wrote: On May 30, 1:47 pm, wrote: "DirtRoadie" wrote in message ....http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR If you look at the first clip his speed increases from four secound between posts to three seconds, now look carefully at his front wheel. *It is swaying from side to side due to high pedalling effort despite steering input to keep the bike straight. *There is no stroll in the park here. Motors have advanced somewhat in the last twenty years and compact arrangments are possible. *I dont know if these same compact motors have the efficiency required to utilise small battery packs that would fit around the frame. *It seems highly unlikely that sufficient strength of the drive to the axle (within a normal size bottom bracket) be obtained for usable levels of assisted torque. *I am open to be proved wrong on both these items. If he's in the running at all, 100 extra watts for 15 minutes will make plenty of difference, is not technically difficult to accomplish, and is not overly burdensome to carry the entire race distance. Lithium polymer cells sustaining 4C discharge rate What is this 4C? and hobby model airplane or car motors are cheap and ubiquitous. For 20W perhaps, not 100W surely? What is their efficiency at high loadings, and the overall eficiency? 12V 2400 mAh packs are small and light. And can safely and reliably source 8-12A for 5 to 15minutes? You can do it for $200 at hobby shop rates, for less than 1 lb total mass. I'm not saying he did so; just pointing out the feasibility. |
#9
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Racing innovation?
thirty-six wrote:
On 31 May, 20:59, "MikeWhy" wrote: thirty-six wrote: On 31 May, 07:03, DirtRoadie wrote: On May 30, 1:47 pm, wrote: "DirtRoadie" wrote in message ...http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR If you look at the first clip his speed increases from four secound between posts to three seconds, now look carefully at his front wheel. It is swaying from side to side due to high pedalling effort despite steering input to keep the bike straight. There is no stroll in the park here. Motors have advanced somewhat in the last twenty years and compact arrangments are possible. I dont know if these same compact motors have the efficiency required to utilise small battery packs that would fit around the frame. It seems highly unlikely that sufficient strength of the drive to the axle (within a normal size bottom bracket) be obtained for usable levels of assisted torque. I am open to be proved wrong on both these items. If he's in the running at all, 100 extra watts for 15 minutes will make plenty of difference, is not technically difficult to accomplish, and is not overly burdensome to carry the entire race distance. Lithium polymer cells sustaining 4C discharge rate What is this 4C? and hobby model airplane or car motors are cheap and ubiquitous. For 20W perhaps, not 100W surely? What is their efficiency at high loadings, and the overall eficiency? 12V 2400 mAh packs are small and light. And can safely and reliably source 8-12A for 5 to 15minutes? 1C is the amp hr rating; 4C is 4 times the amp hr rating. Discharge and charge rates are specified by the cell manufacturer this way. 4C discharge rate on 2400 mAh cells is 9.6 A. Brushless motors can have efficiency above 90%. It can be possible to design a motor and winding for best efficiency at the the target power draw and rpm, say 9 A at 90 rpm. 80% eta and higher is probable. 100 W and higher is no problem at all. I used to rewind CDROM drive motors for 150 W, to power foam airplanes. The torque requirement at 90 rpm will be quite a bit different. There's a bit of room in the BB for a large bevel gear and some reduction. Fewer windings with larger gauge wire should do it. A metal frame is a reasonably good heatsink, for both the motor and batteries. It's feasible to squeeze 100W for 15 minutes from a lightweight and small enough package. |
#10
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Racing innovation?
On May 31, 2:48*pm, "MikeWhy" wrote:
thirty-six wrote: On 31 May, 20:59, "MikeWhy" wrote: thirty-six wrote: On 31 May, 07:03, DirtRoadie wrote: On May 30, 1:47 pm, wrote: "DirtRoadie" wrote in message ...http://www.youtube.com/watch?v=8Nd13ARuvVE What a movie, can't think how cancellara could have cheated and gotten away with it. It's an interesting conspiracy, but too late to prove anything. Wow a lot of work on creating the video and it's all just a conspiracy. Especially suggesting that a simple gear shift (watch the cadence) is a "suspicious movement" of his hand. Then again, Cancellara did make it look as if he had a motor. The device seems interesting, but it certainly does not seem as if a bottom bracket drive could be very effective in light of the gear reduction that would seemingly be needed for a small electric motor assembly (i.e. fits in down tube) to be matched to pedaling cadence. DR If you look at the first clip his speed increases from four secound between posts to three seconds, now look carefully at his front wheel. It is swaying from side to side due to high pedalling effort despite steering input to keep the bike straight. There is no stroll in the park here. Motors have advanced somewhat in the last twenty years and compact arrangments are possible. I dont know if these same compact motors have the efficiency required to utilise small battery packs that would fit around the frame. It seems highly unlikely that sufficient strength of the drive to the axle (within a normal size bottom bracket) be obtained for usable levels of assisted torque. I am open to be proved wrong on both these items. If he's in the running at all, 100 extra watts for 15 minutes will make plenty of difference, is not technically difficult to accomplish, and is not overly burdensome to carry the entire race distance. Lithium polymer cells sustaining 4C discharge rate What is this 4C? and hobby model airplane or car motors are cheap and ubiquitous. For 20W perhaps, not 100W surely? *What is their efficiency at high loadings, and the overall eficiency? 12V 2400 mAh packs are small and light. And can safely and reliably source 8-12A for 5 to 15minutes? 1C is the amp hr rating; 4C is 4 times the amp hr rating. Discharge and charge rates are specified by the cell manufacturer this way. 4C discharge rate on 2400 mAh cells is 9.6 A. Brushless motors can have efficiency above 90%. It can be possible to design a motor and winding for best efficiency at the the target power draw and rpm, say 9 A at 90 rpm. 80% eta and higher is probable. 100 W and higher is no problem at all. I used to rewind CDROM drive motors for 150 W, to power foam airplanes. The torque requirement at 90 rpm will be quite a bit different. There's a bit of room in the BB for a large bevel gear and some reduction. Fewer windings with larger gauge wire should do it. A metal frame is a reasonably good heatsink, for both the motor and batteries. It's feasible to squeeze 100W for 15 minutes from a lightweight and small enough package.- Hide quoted text - - Show quoted text - If the motor is not on, does it drag? -- Jay Beattie. |
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