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The plot thickens in the electronic age...

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The plot thickens in the electronic age...

Old 01-16-14, 07:09 AM
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Campag4life
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The plot thickens in the electronic age...

https://velonews.competitor.com/2014/...smitter_313589

Gotta wonder where we are heading. Programmable shifting? Power taps interfacing with electronic shifting and automatic shifting based upon cadence and load by selecting a preferred algorithm?

Garmin talking to electronic shifting is clearly here or will be shortly.

Crazy how this is evolving.

My immediate reaction was that of opportunity for sabotage when jamming shifting of a competitor's race bike.

Comments?

Last edited by Campag4life; 01-16-14 at 07:14 AM.
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Old 01-16-14, 07:25 AM
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Reminds me of the intermediate stage between manual and automatic shifting of automobiles. If I remember correctly (I was like 3 or 4), there were some transmissions in the early '50s (Desoto) that had you had to shift by letting up on the gas as if you were between gears, but there was no clutch or stick. It was semi-automatic so to speak. I may have this a little screwed up, but I do remember something between manual and automatic. Maybe that is where we are now with the manually operated electronic shifting. Fully automatic is coming, we just didn't realize it. At least we will have 22 gears whereas the early automatic cars only had two.
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Old 01-16-14, 07:35 AM
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Originally Posted by rpenmanparker View Post
Reminds me of the intermediate stage between manual and automatic shifting of automobiles. If I remember correctly (I was like 3 or 4), there were some transmissions in the early '50s (Desoto) that had you had to shift by letting up on the gas as if you were between gears, but there was no clutch or stick. It was semi-automatic so to speak. I may have this a little screwed up, but I do remember something between manual and automatic. Maybe that is where we are now with the manually operated electronic shifting. Fully automatic is coming, we just didn't realize it. At least we will have 22 gears whereas the early automatic cars only had two.
To put a finer technical point on automatic shifting which exists on current motorcycles and automobiles, there is greater opportunity for electronic synergy between the engine and the trans than would be available on a pedal power road bike. The way it works with lets say for a current automobile is...when a shift is about to occur as engine RPM and road speed increase based upon load and engine vacuum, throttle position is electronically closed fractionally and ignition timing is re-tarded slightly to 'soften' the shift. This dramatically improves shift quality and gives it a more seamless quality. Automatic shifting on a bicycle will be more challenging because rider watt output can't be tweaked as readily as with an electronic motor or gasoline engine. Some accommodation could be made with a fluid coupler or torque converter to soften shifts made under rider load but of course this would reduce power efficiency of the rider to the road. If a rider doesn't know when a shift is coming, then a rider isn't going to reduce power to make the shift more seamless.
Will be quite interesting to see where this will lead.

PS: noted technology will likely also affect the wire harness on future electronic shifting groupsets. Wireless shifting is like part of this architecture and therefore amount of wire stringing won't be as invasive....not unlike wireless bike computers taking to sending units that are not connected with a harness.

Last edited by Campag4life; 01-16-14 at 07:48 AM.
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Old 01-16-14, 07:53 AM
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It may be an improvement for some. Although I can't imagine using automatic shifting myself. It's the same thing with cars. I don't like automatic transmission in them either
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Old 01-16-14, 07:59 AM
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IIRC, automatic shifting on bicycles was done decades ago and for an avid cyclist was a total waste. The link between power source, transmission and resulting speed with a human is too variable and being in the zone for a given situation is not achievable through electronics unless there is a bio-mechanical connection.
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Old 01-16-14, 08:06 AM
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I have been riding for 30 plus years, before index shifters, which I thought was heresy when they came out but eventually joined the club, then STI which was great; currently do not like the new electronic shifters, just an old man's opinion
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Old 01-16-14, 08:09 AM
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Originally Posted by Campag4life View Post
To put a finer technical point on automatic shifting which exists on current motorcycles and automobiles, there is greater opportunity for electronic synergy between the engine and the trans than would be available on a pedal power road bike. The way it works with lets say for a current automobile is...when a shift is about to occur as engine RPM and road speed increase based upon load and engine vacuum, throttle position is electronically closed fractionally and ignition timing is re-tarded slightly to 'soften' the shift. This dramatically improves shift quality and gives it a more seamless quality. Automatic shifting on a bicycle will be more challenging because rider watt output can't be tweaked as readily as with an electronic motor or gasoline engine. Some accommodation could be made with a fluid coupler or torque converter to soften shifts made under rider load but of course this would reduce power efficiency of the rider to the road. If a rider doesn't know when a shift is coming, then a rider isn't going to reduce power to make the shift more seamless.
Will be quite interesting to see where this will lead.
I personally don't think we'll see automatic shifting adopted for bicycles on a large scale, other than maybe some niche markets. Might be applicable for strictly commuting purposes, maybe tourism/joyriding rental, etc.

The intentions of automatic shifting in a car/truck/motorcycle vs. a bicycle would be completely different. In a car you are doing something that has to be done: shifting up through gears (incrementally adjusting torque and power applied to the road) to reach a certain speed, whether that's 25 through residential areas or 75 on the freeway. I can't think of any serious road cyclist riding for fitness, racing, etc who would want something like that. Everyone's cadences are different, power output fades as rides go on; there are too many variables to list. Can you imagine trying to do a power-based interval workout and be locked into a shifting curve?

I could definitely see an electronic IVT of some sort coming along before automatic shifting. Using a button (touchpad???) on a brake lever to infinitely adjust a NuVinci hub or something similar without cables, etc? I could get used to that.
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Old 01-16-14, 08:11 AM
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Originally Posted by OldTryGuy View Post
IIRC, automatic shifting on bicycles was done decades ago and for an avid cyclist was a total waste. The link between power source, transmission and resulting speed with a human is too variable and being in the zone for a given situation is not achievable through electronics unless there is a bio-mechanical connection.
https://www.disraeligears.co.uk/Site/...erailleur.html
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Old 01-16-14, 08:19 AM
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It's very interesting consider automatic shifting on bikes where the shifts are based on a complex algorithm that inputs route data (like total distance, road grade), historic rider performance parameters (like target heart rate, power threshold, recovery time, etc.), climate conditions (rain, wind speed, temp, which could be locally sensed or pulled in from web), and that might integrate a plan display that would alert ahead of shifts so that the rider could be prepared to go harder or pull back...

Wow, pretty cool idea. Especially if it has a maual override option!
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Old 01-16-14, 08:40 AM
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Originally Posted by kv501 View Post
I personally don't think we'll see automatic shifting adopted for bicycles on a large scale, other than maybe some niche markets. Might be applicable for strictly commuting purposes, maybe tourism/joyriding rental, etc.

The intentions of automatic shifting in a car/truck/motorcycle vs. a bicycle would be completely different. In a car you are doing something that has to be done: shifting up through gears (incrementally adjusting torque and power applied to the road) to reach a certain speed, whether that's 25 through residential areas or 75 on the freeway. I can't think of any serious road cyclist riding for fitness, racing, etc who would want something like that. Everyone's cadences are different, power output fades as rides go on; there are too many variables to list. Can you imagine trying to do a power-based interval workout and be locked into a shifting curve?

I could definitely see an electronic IVT of some sort coming along before automatic shifting. Using a button (touchpad???) on a brake lever to infinitely adjust a NuVinci hub or something similar without cables, etc? I could get used to that.
I think a CVT hub with computer interface maybe the future but it maybe 20 years out. This would solve the finite gap issue of chain jumping from one cog to another and would allow for constant pedal force. Then having programmability which accounts for rider wattage, cadence etc to fine tune this interface would be appealing.
Honestly this stuff is coming. In fact bike tech meet electronics is taking on a new form with supplemental motor power or E bikes. Specialized Turbo for example matches rider power with motor power. 200W from rider = 200 motor power match for 400 watts total. All programmable. No reason IVT couldn't be incorporated. Super conductor motor magnets and a revolution in battery storage will take the whole thing to a completely different level.

How CVT works:
https://www.youtube.com/watch?v=DldUaOWnKQM
PS: I envision a miniature CVT transmission between a single cog rear hub back wheel and small front single ring.
Computer programmable based upon rider preference and strength.

Last edited by Campag4life; 01-16-14 at 08:51 AM.
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Old 01-16-14, 08:49 AM
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Not sure about the automatic shifting desirability, but I can honestly say that I love the Di2 shifting on my new bike. I've been trying to keep my cadence in the 85 rmp range, and shifting is almost effortless, including the front chain rings. I shift much more now than on my old bike, and I have no desire to ever go back. Old dogs can learn new tricks...
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Old 01-16-14, 08:53 AM
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Originally Posted by Yankeetowner View Post
Not sure about the automatic shifting desirability, but I can honestly say that I love the Di2 shifting on my new bike. I've been trying to keep my cadence in the 85 rmp range, and shifting is almost effortless, including the front chain rings. I shift much more now than on my old bike, and I have no desire to ever go back. Old dogs can learn new tricks...
And Di2 today is an infant child that can evolve into something much better or part of a supplemental power source.
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Old 01-16-14, 08:59 AM
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My wife would love automatic shifting, but she can't chew gum and rub her stomach at the same time. Very much a person who cannot do two things at once when it comes to biking. I can't see how it would be all that beneficial to me though. I would rather have the ability to pick the cog on my own and not have some computer doing it.
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Old 01-16-14, 09:01 AM
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Originally Posted by Campag4life View Post
I think a CVT hub with computer interface maybe the future but it maybe 20 years out. This would solve the finite gap issue of chain jumping from one cog to another and would allow for constant pedal force. Then having programmability which accounts for rider wattage, cadence etc to fine tune this interface would be appealing.
Honestly this stuff is coming. In fact bike tech meet electronics is taking on a new form with supplemental motor power or E bikes. Specialized Turbo for example matches rider power with motor power. 200W from rider = 200 motor power match for 400 watts total. All programmable. No reason IVT couldn't be incorporated. Super conductor motor magnets and a revolution in battery storage will take the whole thing to a completely different level.

How CVT works:
https://www.youtube.com/watch?v=DldUaOWnKQM
PS: I envision a miniature CVT transmission between a single cog rear hub back wheel and small front single ring.
Computer programmable based upon rider preference and strength.
I agree but I don't think it's 20 years out. Tech advancements happen exponentially faster.

My thinking with the "touch pad" comment earlier was an IVT hub that could be adjusted by a touch-sensitive area on a brake lever. Think the "scroll wheel" on an Apple mouse. Want more resistance to match your power/cadence? "scroll" down on the lever. Less resistance, "scroll" up. Want to still have the option of preset gear-inches, make it programmable to have 11, 12, 13... predefined speeds that you can shift through like a cassette.

People might think it's a crazy idea, but 15 years ago no one would have realistically thought we'd have servo motors doing our shifting for us (me included). I was as skeptical as everyone else when it first came out, but after buying Ultegra Di2 I'll never go back to mechanical. Totally reliable, adjustment free, and fewer moving parts. All the things that people said wouldn't happen.
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Old 01-16-14, 09:03 AM
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Originally Posted by chaadster View Post
It's very interesting consider automatic shifting on bikes where the shifts are based on a complex algorithm that inputs route data (like total distance, road grade), historic rider performance parameters (like target heart rate, power threshold, recovery time, etc.), climate conditions (rain, wind speed, temp, which could be locally sensed or pulled in from web), and that might integrate a plan display that would alert ahead of shifts so that the rider could be prepared to go harder or pull back...

Wow, pretty cool idea. Especially if it has a maual override option!
I think manual override would get a lot of use. I really can't think of how an automatic shifting bike would be an advantage. Maybe for people who are easily confused about shifting, but not for "real" cyclists.
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Old 01-16-14, 09:08 AM
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I would never use an automatic shifting bike. It would have no idea how hard I want to go at any given time.
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Old 01-16-14, 09:24 AM
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Originally Posted by Campag4life View Post
To put a finer technical point on automatic shifting which exists on current motorcycles and automobiles, there is greater opportunity for electronic synergy between the engine and the trans than would be available on a pedal power road bike. The way it works with lets say for a current automobile is...when a shift is about to occur as engine RPM and road speed increase based upon load and engine vacuum, throttle position is electronically closed fractionally and ignition timing is re-tarded slightly to 'soften' the shift. This dramatically improves shift quality and gives it a more seamless quality. Automatic shifting on a bicycle will be more challenging because rider watt output can't be tweaked as readily as with an electronic motor or gasoline engine. Some accommodation could be made with a fluid coupler or torque converter to soften shifts made under rider load but of course this would reduce power efficiency of the rider to the road. If a rider doesn't know when a shift is coming, then a rider isn't going to reduce power to make the shift more seamless.
Will be quite interesting to see where this will lead.

PS: noted technology will likely also affect the wire harness on future electronic shifting groupsets. Wireless shifting is like part of this architecture and therefore amount of wire stringing won't be as invasive....not unlike wireless bike computers taking to sending units that are not connected with a harness.
Also, pedaling isn't nearly as uniform as controlling the throttle on a car. If you slack off for a second for any reason, grabbing a water bottle, dodging a pothole whatever, is the transmission going to downshift mindlessly? That could be very disconcerting and inconvenient.
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Old 01-16-14, 09:28 AM
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Here is an interesting thought, with no manual override, to sprint you would have to jump in the lower gear, and the shift to the higher gear would follow later while you were maybe already standing. That could be very interesting kind of along the lines of what C4L was sayng.
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Old 01-16-14, 09:41 AM
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Originally Posted by tsurr View Post
currently do not like the new electronic shifters, just a seasoned veteran's opinion
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Old 01-16-14, 10:33 AM
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Pretty soon, you won't even have to ride a bike. You'll be able to buy a device that lets you type in the average speed you want, and uploads it directly to strava, while you post on bike forums from Starbucks, wearing your kit.
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Old 01-16-14, 10:37 AM
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Originally Posted by Seattle Forrest View Post
Pretty soon, you won't even have to ride a bike. You'll be able to buy a device that lets you type in the average speed you want, and uploads it directly to strava, while you post on bike forums from Starbucks, wearing your kit.
And only 41 posters would buy it.
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Old 01-16-14, 10:37 AM
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If you have to charge the bicycle to ride it, I don't want it.
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Old 01-16-14, 10:40 AM
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Mechanical cables are still the most reliable and cost effective way to shift gears on a bike, and I don't see that changing any time soon.
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Old 01-16-14, 11:22 AM
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Originally Posted by Campag4life View Post
when a shift is about to occur as engine RPM and road speed increase based upon load and engine vacuum, throttle position is electronically closed fractionally and ignition timing is re-tarded slightly to 'soften' the shift. This dramatically improves shift quality and gives it a more seamless quality.
This is all done for shift feel, and the biggest reason to do it is due to the torque spike that would otherwise occur. The torque spike is due to the fact that during an up shift the transmission is effectively decelerating the engine from its speed in the lower gear to the equivalent engine speed in the higher gear. The engines rotational inertia has to go somewhere, so the basic objective is to reduce engine torque output by about the same amount as the deceleration of the engine will add.

Also, it's not like this is a necessity. Automatics have obviously been around for much longer than the ability to electronically reduce engine output. This is a nicety, not a necessity.

Originally Posted by Campag4life View Post
Automatic shifting on a bicycle will be more challenging because rider watt output can't be tweaked as readily as with an electronic motor or gasoline engine.
Given the rotating inertia's involved, I don't think it is an issue.
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Old 01-16-14, 11:33 AM
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Originally Posted by SirHustlerEsq View Post
If you have to charge the bicycle to ride it, I don't want it.

your in luck, only the battery has to be charged,
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