On Thu, 2 Jan 2025 10:06:08 -0600, AMuzi <[email protected]> wrote:
I take from that, you think the actual impact/height
change/velocity change etc from various irregular surfaces
can be quantified for any given random gravel (or road)
experience and used to compare efficiency for other iterations.
This is close, but not quite what you're asking.
"Energy Harvesting from Bicycle Vibrations by Means of Tuned
Piezoelectric Generators"
<https://www.mdpi.com/2079-9292/9/9/1377> <https://mdpi-res.com/d_attachment/electronics/electronics-09-01377/article_deploy/electronics-09-01377-v2.pdf?version=1598515211>
On PDF page 14, it proclaims:
"8. Prediction of Generated Power
The electrical power harvested by a piezo-harvester is very low (in
the order of a few mW), so highly-efficient power management units
(PMU) have to be used for energy conversion. The output voltage of the piezo-harvester is a random signal with a main harmonic component at
the resonance vibration frequency of the cantilever. On the other
hand, electronic loads (such as a battery for energy storage and/or a portable device which can be mounted on a bicycle) are typically fed
by DC voltage; therefore, interface electronic circuits between the piezo-harvester and the load are made up by a rectifier (for AC to DC
voltage conversion), an electrolytic capacitor for voltage leveling
and energy storage, and DC-DC converter for impedance matching with
the electronic load resistance."
Page 17 has a table of generated power at various speeds.
Of course it's possible to optimize the bicycle design, material
(tire) selection, road surface profile, etc to produce the most power
output. Presumably, the generated electric power will be used to
power an electric and mechanical doping system. The problem is that
when you're starting with milliwatts, it's a long way to go before
sufficient power can be harvested to make a difference in a race or on
a ride.
On Fri Jan 3 20:27:04 2025 Jeff Liebermann wrote:
On Thu, 2 Jan 2025 10:06:08 -0600, AMuzi <[email protected]> wrote:
I take from that, you think the actual impact/height
change/velocity change etc from various irregular surfaces
can be quantified for any given random gravel (or road)
experience and used to compare efficiency for other iterations.
This is close, but not quite what you're asking.
"Energy Harvesting from Bicycle Vibrations by Means of Tuned
Piezoelectric Generators"
<https://www.mdpi.com/2079-9292/9/9/1377>
<https://mdpi-res.com/d_attachment/electronics/electronics-09-01377/article_deploy/electronics-09-01377-v2.pdf?version98515211>
On PDF page 14, it proclaims:
"8. Prediction of Generated Power
The electrical power harvested by a piezo-harvester is very low (in
the order of a few mW), so highly-efficient power management units
(PMU) have to be used for energy conversion. The output voltage of the
piezo-harvester is a random signal with a main harmonic component at
the resonance vibration frequency of the cantilever. On the other
hand, electronic loads (such as a battery for energy storage and/or a
portable device which can be mounted on a bicycle) are typically fed
by DC voltage; therefore, interface electronic circuits between the
piezo-harvester and the load are made up by a rectifier (for AC to DC
voltage conversion), an electrolytic capacitor for voltage leveling
and energy storage, and DC-DC converter for impedance matching with
the electronic load resistance."
Page 17 has a table of generated power at various speeds.
Of course it's possible to optimize the bicycle design, material
(tire) selection, road surface profile, etc to produce the most power
output. Presumably, the generated electric power will be used to
power an electric and mechanical doping system. The problem is that
when you're starting with milliwatts, it's a long way to go before
sufficient power can be harvested to make a difference in a race or on
a ride.
What do you think you're saying? There is essentually no pezo power from
a bike with 32 mm tires at the correct pressure. Bike riders are being
told that they should ride 40 mm tires. You don't ride bicycles so you
have no first hand knowledge of anything so stop acting as if you do.
On Fri Jan 3 20:27:04 2025 Jeff Liebermann wrote:
On Thu, 2 Jan 2025 10:06:08 -0600, AMuzi <[email protected]> wrote:
I take from that, you think the actual impact/height
change/velocity change etc from various irregular surfaces
can be quantified for any given random gravel (or road)
experience and used to compare efficiency for other iterations.
This is close, but not quite what you're asking.
"Energy Harvesting from Bicycle Vibrations by Means of Tuned
Piezoelectric Generators"
<https://www.mdpi.com/2079-9292/9/9/1377>
<https://mdpi-res.com/d_attachment/electronics/electronics-09-01377/article_deploy/electronics-09-01377-v2.pdf?version=1598515211>
On PDF page 14, it proclaims:
"8. Prediction of Generated Power
The electrical power harvested by a piezo-harvester is very low (in
the order of a few mW), so highly-efficient power management units
(PMU) have to be used for energy conversion. The output voltage of the
piezo-harvester is a random signal with a main harmonic component at
the resonance vibration frequency of the cantilever. On the other
hand, electronic loads (such as a battery for energy storage and/or a
portable device which can be mounted on a bicycle) are typically fed
by DC voltage; therefore, interface electronic circuits between the
piezo-harvester and the load are made up by a rectifier (for AC to DC
voltage conversion), an electrolytic capacitor for voltage leveling
and energy storage, and DC-DC converter for impedance matching with
the electronic load resistance."
Page 17 has a table of generated power at various speeds.
Of course it's possible to optimize the bicycle design, material
(tire) selection, road surface profile, etc to produce the most power
output. Presumably, the generated electric power will be used to
power an electric and mechanical doping system. The problem is that
when you're starting with milliwatts, it's a long way to go before
sufficient power can be harvested to make a difference in a race or on
a ride.
What do you think you're saying?
There is essentually no pezo power from a bike with 32 mm tires
at the correct pressure. Bike riders are being told that they
should ride 40 mm tires.
You don't ride bicycles so you have no first hand knowledge of
anything so stop acting as if you do.
On 6/20/2025 4:43 PM, Roger Merriman wrote:
Who is saying they should ride 40mm tyres?
I’ve seen some reviews of 40mm road tyres which broadly comes down to
comfortable but almost certainly slower than 28/32 though non racers may
well make that choice.
Not seen anyone claiming 40mm tyres should be ridden quite apart from
anything else relatively few road bikes will fit 40mm.
These days I think the main proponent of such wide tires is Jan Heine, publisher of Bicycle Quarterly. IIRC he rides something like 40mm very frequently even on smooth-ish pavement. But his articles seem to
describe his typical routes as having lots of gravel.
On 6/21/2025 3:59 AM, Roger Merriman wrote:
Frank Krygowski <[email protected]> wrote:
On 6/20/2025 4:43 PM, Roger Merriman wrote:Even with the caveat that he’s not really mainstream, he sells sub 40mm
Who is saying they should ride 40mm tyres?
I’ve seen some reviews of 40mm road tyres which broadly comes down to >>>> comfortable but almost certainly slower than 28/32 though non racers may >>>> well make that choice.
Not seen anyone claiming 40mm tyres should be ridden quite apart from
anything else relatively few road bikes will fit 40mm.
These days I think the main proponent of such wide tires is Jan Heine,
publisher of Bicycle Quarterly. IIRC he rides something like 40mm very
frequently even on smooth-ish pavement. But his articles seem to
describe his typical routes as having lots of gravel.
tyres 30mm/33 or so?
Don’t recall him being quite so literal, my way or nothing, all advice and >> indeed reviews seem to be it depends particularly at the 40mm end!
Right, he's not commanding we all ride 40mm tires. What salesman would
do that? But he spends a good amount of his text output praising ever
wider tires, even for normal pavement.
Looks like he sells one 28mm tire in 700c, and his road tires go up to
55mm.
<https://www.renehersecycles.com/product-category/components/tires/700c/>
Who is saying they should ride 40mm tyres?
I?ve seen some reviews of 40mm road tyres which broadly comes down to comfortable but almost certainly slower than 28/32 though non racers may
well make that choice.
Not seen anyone claiming 40mm tyres should be ridden quite apart from anything else relatively few road bikes will fit 40mm.
On Fri Jun 20 20:43:18 2025 Roger Merriman wrote:
Who is saying they should ride 40mm tyres?
I?ve seen some reviews of 40mm road tyres which broadly comes down to
comfortable but almost certainly slower than 28/32 though non racers may
well make that choice.
Not seen anyone claiming 40mm tyres should be ridden quite apart from
anything else relatively few road bikes will fit 40mm.
I most certainly have not tried this since none of my bikes would mount
tires that wide but CyclingNews does recommend it.
https://www.cyclingnews.com/features/lab-tested-40mm-road-tyres-are-faster-for-nearly-everyone-and-heres-why/
Now I surely was surprised at the increase in average speed using 32 mm
tires (using very slow Gatorskins Hardshells) and also a very noticeable increase in comfort and another advantage is that they roll right over pavement cracks of quite a large size. You don't have to swerve to try
and cross at a closer to right angle.
But if you look at the rolling resistance site:
Most of the lowest rolling resistance tests are on 25 mm tires.
The rolling resistance tests need to be greatly changed since it does not have "bumps" of the same size as those on open roads.
I had a gravel bike with 38 mm tires and I road with the group on a 37
mile ride with 3700 feet of climbing. Now these were gravel tires which
were semi-knobbies. But I had no trouble keeping up with the fast group. (well except for a couple of 17 year old twins.)
The new bikes such as the Time Sylon has room to fit really fat tires.
On Fri, 20 Jun 2025 20:23:19 GMT, cyclintom <[email protected]>
wrote:
On Fri Jan 3 20:27:04 2025 Jeff Liebermann wrote:
On Thu, 2 Jan 2025 10:06:08 -0600, AMuzi <[email protected]> wrote:
I take from that, you think the actual impact/height
change/velocity change etc from various irregular surfaces
can be quantified for any given random gravel (or road)
experience and used to compare efficiency for other iterations.
This is close, but not quite what you're asking.
"Energy Harvesting from Bicycle Vibrations by Means of Tuned
Piezoelectric Generators"
<https://www.mdpi.com/2079-9292/9/9/1377>
<https://mdpi-res.com/d_attachment/electronics/electronics-09-01377/article_deploy/electronics-09-01377-v2.pdf?version=1598515211>
On PDF page 14, it proclaims:
"8. Prediction of Generated Power
The electrical power harvested by a piezo-harvester is very low (in
the order of a few mW), so highly-efficient power management units
(PMU) have to be used for energy conversion. The output voltage of the
piezo-harvester is a random signal with a main harmonic component at
the resonance vibration frequency of the cantilever. On the other
hand, electronic loads (such as a battery for energy storage and/or a
portable device which can be mounted on a bicycle) are typically fed
by DC voltage; therefore, interface electronic circuits between the
piezo-harvester and the load are made up by a rectifier (for AC to DC
voltage conversion), an electrolytic capacitor for voltage leveling
and energy storage, and DC-DC converter for impedance matching with
the electronic load resistance."
Page 17 has a table of generated power at various speeds.
Of course it's possible to optimize the bicycle design, material
(tire) selection, road surface profile, etc to produce the most power
output. Presumably, the generated electric power will be used to
power an electric and mechanical doping system. The problem is that
when you're starting with milliwatts, it's a long way to go before
sufficient power can be harvested to make a difference in a race or on
a ride.
What do you think you're saying?
I was responding to Andrews comments on using energy harvesting
technology to generate electrical power. You were responding to my
comments from 6 months ago. Are you lacking in suitable topics to demonstrate your ineptitude, are you just resurrecting old discussions because you can't seem to find suitable replies to current topics, or
are you having difficulties operating your NewsHosting.com news
reader?
There is essentually no pezo power from a bike with 32 mm tires
at the correct pressure. Bike riders are being told that they
should ride 40 mm tires.
What is the "pezo" power? Do you mean power generated by piezo
electric methods? Who is telling riders to ride 40 mm tires? It's
certainly not me? So why are you complaining about something I
obviously didn't say?
You don't ride bicycles so you have no first hand knowledge of
anything so stop acting as if you do.
I see. Not riding a bicycle somehow makes me ignorant on how energy harvesting functions on a bicycle (or any vehicle). <https://en.wikipedia.org/wiki/Energy_harvesting> <https://en.wikipedia.org/wiki/Energy_harvesting#Energy_from_smart_roads_and_piezoelectricity>
Did you have classes in college on engineering mechanics, statics,
dynamics, materials, motors, generators, thermodynamics, fluidics,
physics and such? Oh, I forgot that you are self taught and know all
those topics because you "read out" all their books on "non-fiction"
topics from 3 public and 1 military libraries in an amazingly short
period of time.
06/07/2022 <https://groups.google.com/g/rec.bicycles.tech/c/QNPNSofg064/m/Xaamy15iBQAJ> "I would warrant that I've read more than 20 times more books than you
have. I read out three public libraries, the military library and all
of the books I used to gain the knowledge to become an engineer."
That sounds very much like you are in favor of "book learning" since
you obviously would not have been able to obtain "hands on" experience
with real products on the technologies I mentioned. Are you perhaps
claiming that your can "book learn" complex engineering topics, while everyone has to learn from "hands on" experience? That doesn't quite
work.
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