Doing a dumb experiment...
#76
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Nobody ever heard of a dollar bill or a sticker patch? They work. Used one this weekend (sticker patch).
I accept fully that this is borne out of too much time on one's hands, so cannot really give it any crap.
I just say, you should do some kind of bogus test like a roll down a hill to see if the rollout of the inverted tire was better or worse...............like GCN does science.
Also, perhaps, do a test where you fill the tube with helium.
I accept fully that this is borne out of too much time on one's hands, so cannot really give it any crap.
I just say, you should do some kind of bogus test like a roll down a hill to see if the rollout of the inverted tire was better or worse...............like GCN does science.
Also, perhaps, do a test where you fill the tube with helium.
To me an "experiment" needs to test some hypothesis. Since then OP has clarified that he meant "experiment" in the sense of trying something for no particular reason. Hence my inference (I thought it a generous one) was dismissed by OP.
#77
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IIRC, there was someone on YouTube who tried helium in their BMX tires. Didn't really do much.
Here's one video. Although there are others on YouTube. See, I'm not the only one willing to do dumb experiments.
https://youtu.be/vJNg4njdyLo
Here's one video. Although there are others on YouTube. See, I'm not the only one willing to do dumb experiments.
https://youtu.be/vJNg4njdyLo
#78
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On the other hand, you could save some 15 g of rotational mass!
(I recently did a little calculation on this just out of interest; don't remember the exact figures, but it was something like that. For mountain bike tires it would be even more, over 20g!)
#80
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Found this video where someone decided to try different methods to "drift" their bike. One of the methods they tried (starts at 4:07 in the video) is turning the tire inside out. Looks like the tire stayed on the rim at 50 PSI, but the rough surface combined with the rough riding (skidding the tire across the pavement) caused the nylon cords to give way, causing the tube to bulge out and burst.
So, there's the answer. I don't need to do the experiment as someone else beat me to it.
So, there's the answer. I don't need to do the experiment as someone else beat me to it.
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Found this video where someone decided to try different methods to "drift" their bike. One of the methods they tried (starts at 4:07 in the video) is turning the tire inside out. Looks like the tire stayed on the rim at 50 PSI, but the rough surface combined with the rough riding (skidding the tire across the pavement) caused the nylon cords to give way, causing the tube to bulge out and burst.
https://youtu.be/tgrLCIuHhLw?t=247
So, there's the answer. I don't need to do the experiment as someone else beat me to it.
https://youtu.be/tgrLCIuHhLw?t=247
So, there's the answer. I don't need to do the experiment as someone else beat me to it.
#82
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Most anticlimactic experiment thread since https://www.bikeforums.net/general-c...s-70t-pic.html
#83
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Darwin rushed to publish his Origin of the Species because he heard that a competitor was about to publish similar findings.
Liebnitz' invention of calculus was overshadowed by Newton's invention of calculus because Newton happened to be the head of the Royal Society.
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#84
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A regular tube can't hold the pressure to offset your weight, unless you go with a truck tube (large size).
On the other hand, I've found the thornproof tubes to be odd beasts.
A few years ago I had a blowout (blown off bead) with my 16x3 trailer tires.
I was stuck with whatever I could scrounge at Walmart. I was able to get the tire to hold by using a 16x(1.75?) thornproof tube blown up to about 30 PSI, and holding about 3" of blown bead in place.
Now, trying to hold say a 26" thornproof tube on a 26" rim could be problematic.
One option might be to downsize one size, so try a 24" thornproof tube on a 26" rim, or similar. But, there still would be a risk of rolling the tube.
You could also try gluing the tube onto a sewup/tubular rim. If you haven't used those, they have a concave surface where the tire is glued to. One still as to deal with stretch. I'd probably again try an undersized tube such as 26" or 650B on 700c.
#85
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https://youtu.be/5Zde8AWWKeI
Wonder how the developers of that tire would've been received on the BikeForums...
Wonder how the developers of that tire would've been received on the BikeForums...
https://www.bikeforums.net/general-c...zip-tires.html
https://www.bikeforums.net/winter-cy...ter-tires.html
They appeared to be an interesting solution, but not fitting my riding. However, I could imagine them for occasional winter use.
If you like the think out of the box tire stuff... Have you seen the Gaadi Rubena?
#86
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Most anticlimactic experiment thread since https://www.bikeforums.net/general-c...s-70t-pic.html
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The thread was locked, and the OP has vanished.
I've been riding a 70T off and on for a couple of years. One of my favorite hill climbing and trailer towing sprockets.
I'm a bit low on the miles this year. But, over 600 miles on that bike this year, I think.
Not a single speed though.
I've been riding a 70T off and on for a couple of years. One of my favorite hill climbing and trailer towing sprockets.
I'm a bit low on the miles this year. But, over 600 miles on that bike this year, I think.
Not a single speed though.
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#88
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The thread was locked, and the OP has vanished.
I've been riding a 70T off and on for a couple of years. One of my favorite hill climbing and trailer towing sprockets.
I'm a bit low on the miles this year. But, over 600 miles on that bike this year, I think.
Not a single speed though.
I've been riding a 70T off and on for a couple of years. One of my favorite hill climbing and trailer towing sprockets.
I'm a bit low on the miles this year. But, over 600 miles on that bike this year, I think.
Not a single speed though.
And at 50 mph on the flats, it only took you about 12 hours, right?
The absurd speed claims were what made that thread classic.
Love that rig, btw. Never seen anything quite like it.
#89
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The black suitcase trailer is the standard Pocket Rocket travel trailer. The Samsonite Clamshell has been discontinued, but there is a replacement model that works as good or better. With moderate disassembly the bike fits into the suitcase, and the trailer too.
The cat carrier is adapted from a now discontinued Bike Friday cargo trailer. The cat actually seems to be happier in the bike trailer than in the pickup, even if it is cold.
As far as the chainring, I was doing experiments earlier. The small wheels, of course, spin faster than big wheel bikes and require larger rings. But, this one is on the large size. I'll probably change to a 61T or so sometime, in part due to difficulty mounting the derailleur.
I have a lot of low-end power. I don't watch my cadence a lot, but think I could be happy with 30 to 50 RPM.
I suppose I'm a person that wishes to do the experiments myself. And, while I will turn a larger gear than some people, it has also become obvious that after a point that one may generate more power by downshifting rather than upshifting. I.E. Somewhere around force equal to 50% to 100% of one's weight, one maxes out on the ability to repeatedly push down/pull up, and must increase cadence to increase power, which is the general failure of people wishing to calculate an infinite speed increase based simply on gearing increases.
However, different body configurations could approach the problem differently.
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#90
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As far as the bicycle, it is a Pocket Rocket made by Bike Friday here in Eugene, Oregon. Other than the chainring, it is fairly stock from about 20 years ago. They still make the model, but with a few minor updates.
The black suitcase trailer is the standard Pocket Rocket travel trailer. The Samsonite Clamshell has been discontinued, but there is a replacement model that works as good or better. With moderate disassembly the bike fits into the suitcase, and the trailer too.
The cat carrier is adapted from a now discontinued Bike Friday cargo trailer. The cat actually seems to be happier in the bike trailer than in the pickup, even if it is cold.
As far as the chainring, I was doing experiments earlier. The small wheels, of course, spin faster than big wheel bikes and require larger rings. But, this one is on the large size. I'll probably change to a 61T or so sometime, in part due to difficulty mounting the derailleur.
I have a lot of low-end power. I don't watch my cadence a lot, but think I could be happy with 30 to 50 RPM.
I suppose I'm a person that wishes to do the experiments myself. And, while I will turn a larger gear than some people, it has also become obvious that after a point that one may generate more power by downshifting rather than upshifting. I.E. Somewhere around force equal to 50% to 100% of one's weight, one maxes out on the ability to repeatedly push down/pull up, and must increase cadence to increase power, which is the general failure of people wishing to calculate an infinite speed increase based simply on gearing increases.
However, different body configurations could approach the problem differently.
The black suitcase trailer is the standard Pocket Rocket travel trailer. The Samsonite Clamshell has been discontinued, but there is a replacement model that works as good or better. With moderate disassembly the bike fits into the suitcase, and the trailer too.
The cat carrier is adapted from a now discontinued Bike Friday cargo trailer. The cat actually seems to be happier in the bike trailer than in the pickup, even if it is cold.
As far as the chainring, I was doing experiments earlier. The small wheels, of course, spin faster than big wheel bikes and require larger rings. But, this one is on the large size. I'll probably change to a 61T or so sometime, in part due to difficulty mounting the derailleur.
I have a lot of low-end power. I don't watch my cadence a lot, but think I could be happy with 30 to 50 RPM.
I suppose I'm a person that wishes to do the experiments myself. And, while I will turn a larger gear than some people, it has also become obvious that after a point that one may generate more power by downshifting rather than upshifting. I.E. Somewhere around force equal to 50% to 100% of one's weight, one maxes out on the ability to repeatedly push down/pull up, and must increase cadence to increase power, which is the general failure of people wishing to calculate an infinite speed increase based simply on gearing increases.
However, different body configurations could approach the problem differently.
#91
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I suspect the converse is also true--that some people fall into the trap of believing that increasing cadence is the only way to increase speed, and are afraid/discouraged of trying higher gears. Lots of "you'll blow out your knees" stuff that doesn't appear to have any basis in fact going around. I encourage people to try a variety of gears and cadences because I think that people vary enormously in the optimum balance between leg strength vs. CV capacity.
I do have "bad knees", but don't attribute them to cycling. And, they seem to get better the more I ride.
Don't over-stress, but a moderate amount of stress for the body isn't bad.
#92
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Some people have posted that they have bad knees and now mash higher gears because they find that easier on their knees than spinning. I've never had serious knee problems and I'm in my late 50s. I've had people on BF tell me I'm going to develop knee problems because I love the high gears. Any decade now, I guess.
My main point is that people shouldn't be afraid to experiment and see what works best for them, and shouldn't avoid gears that they like because some coach told someone he knew a guy who used to ride in the high gears and now he has arthritis in his knees.
Bicycling is often recommended as rehab for bad knees, so I don't doubt yours feel better, not worse, with more riding.
Since the drama with the inverted tires seems to be over, maybe the thread morph should be to experiments we have tried.
#93
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I did watch the two videos posted above, somewhere.
I'm not sure the E-Bike shredding video is representative of what one's general experience would be, although it does bring up a point of using rubber compounds not designed for traction.
What would a thick smooth tire be like? Thick Slick?
I'm not sure the E-Bike shredding video is representative of what one's general experience would be, although it does bring up a point of using rubber compounds not designed for traction.
What would a thick smooth tire be like? Thick Slick?
#95
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Been done! Check out the video in post #80 and watch them shred a tire in 5 minutes!
We're talking about the well-endowed folding bike now.
We're talking about the well-endowed folding bike now.
#96
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The bead isn't gonna be any bigger with the tyre the wrong way around, so why anyone thinks it's more likely to pop off the rim is beyond me. Likewise with the rest of the structure, which is the shape of a horse shoe, and will still be the shape of a horse shoe when inverted.
Couple of exceptions spring to mind;
Any radial ply will be on the inside.
The inner layers will be tighter, so these will be susceptible to split stress on the outside - likewise the outer layers on the inside will be compressed and bunched, risking deformation and splitting from the afore-mentioned layers.
The heavy tread is likely to damage the tube - use a thin slick tyre for this.
The inner wall, now on the outside, has a layer so thin it's literally just painted on. Therefore it'll make no useful form with the road surface.
All in all you're looking at a tyre with no grip, reduced structural stability, Risk of total failure at the weave.. but I see no reason why the bead would leave the rim unless it was already well off-centre when the tube was inflated.
I also see no practical reason for doing it. Surely if a tyre is damaged that much on the outside, turning it around isn't going to improve anything...
Couple of exceptions spring to mind;
Any radial ply will be on the inside.
The inner layers will be tighter, so these will be susceptible to split stress on the outside - likewise the outer layers on the inside will be compressed and bunched, risking deformation and splitting from the afore-mentioned layers.
The heavy tread is likely to damage the tube - use a thin slick tyre for this.
The inner wall, now on the outside, has a layer so thin it's literally just painted on. Therefore it'll make no useful form with the road surface.
All in all you're looking at a tyre with no grip, reduced structural stability, Risk of total failure at the weave.. but I see no reason why the bead would leave the rim unless it was already well off-centre when the tube was inflated.
I also see no practical reason for doing it. Surely if a tyre is damaged that much on the outside, turning it around isn't going to improve anything...
#98
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I think the idea is that if there is some tension in the cords, it'll squish the rubber in an open crack back closed when the tire is inverted, especially if it has a thick tread.
So, in theory, you save a boot, and it keeps the tube from bulging out.
It may work for a short ride, but one risks further damage to the cords, and any remaining structure could fail catastrophically.
This might only work with certain between types of damage. If the hole is small, it is unnecessary, and if it is too big to conveniently boot, I doubt one would have much success with inverting.
So, in theory, you save a boot, and it keeps the tube from bulging out.
It may work for a short ride, but one risks further damage to the cords, and any remaining structure could fail catastrophically.
This might only work with certain between types of damage. If the hole is small, it is unnecessary, and if it is too big to conveniently boot, I doubt one would have much success with inverting.
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#99
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A thick tread on the outside keeps the cord layer off the road.
The bead isn't necessarily going to work as well inside-out.
Carry something that can be used as a boot.
Last edited by njkayaker; 11-12-19 at 10:41 AM.
#100
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Keep in mind that one of the favorite boots in the USA is American Dollar Bills.
Not a bad thing to carry a couple for emergencies.
Not a bad thing to carry a couple for emergencies.