Go Back  Bike Forums > Bike Forums > General Cycling Discussion
Reload this Page >

What Work Is Being Done For Serious Non Pneumatic Tires?

Notices
General Cycling Discussion Have a cycling related question or comment that doesn't fit in one of the other specialty forums? Drop on in and post in here! When possible, please select the forum above that most fits your post!

What Work Is Being Done For Serious Non Pneumatic Tires?

Old 10-21-19, 08:54 AM
  #51  
livedarklions
Tragically Ignorant
 
livedarklions's Avatar
 
Join Date: Jun 2018
Location: New England
Posts: 15,613

Bikes: Serotta Atlanta; 1994 Specialized Allez Pro; Giant OCR A1; SOMA Double Cross Disc; 2022 Allez Elite mit der SRAM

Mentioned: 62 Post(s)
Tagged: 0 Thread(s)
Quoted: 8186 Post(s)
Liked 9,094 Times in 5,053 Posts
Originally Posted by woodcraft
This would be in the running for the least aero wheel ever.
Or least appetizing pizza.
livedarklions is offline  
Old 11-10-19, 11:27 PM
  #52  
MikeyMK
Cycleway town
 
MikeyMK's Avatar
 
Join Date: Jul 2014
Location: Milton Keynes, England
Posts: 1,402

Bikes: 2.6kw GT LTS e-tandem, 250w Voodoo, 250w solar recumbent trike, 3-speed shopper, Merlin ol/skl mtb, 80cc Ellswick

Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 569 Post(s)
Liked 169 Times in 117 Posts
Originally Posted by MikeyMK
I intend to find out.
​​​​​​
Well, I've now fitted these. With a pair of new tyres, identical to the old ones. Sizing as follows:

Rim - 559 x 50
Tyre - 559 x 60
Tube - 26 x 1.9-2.1
Armour - 559 x 50-63

First thing you notice here is that my sizing doesn't make me a great example. Yes, I'm running 50mm wide rims, and that means Tannus' claims of run-flat ability can be laughed at for starters, especially given the paper-thin, relatively small but baggy 2.35in Schwalbe Fat Frank tyres. These are already excellent for pinch flats though, staying inflated even when the rim itself is broken by a kerb! So Tannus' claims of pinch-flat protection will hopefully mean it helps protect the rim itself from damage. This is very much still valid for me, despite 60mm tyres, because the bike weighs some 45kgs and near ten of them are in the back wheel...

Anyway, despite the wheel with, the armour did tuck nicely into the rim (various sizes are available, and if you're in-between sizes you cut the Armour's skirt shorter). In fact, at low pressure, it was possible to fit it just like a tyre, without the tyre..
Fitting was easy, I put the armour and tube in the tyre first, and offered the lot onto the rim. The first side went on as normal, the second side was just a case of tucking the armour into the rim first, then the tyre's bead as normal after.

So what do they ride like? Well I was expecting worse, but the actual rolling ride quality is slightly improved. It feels a touch more refined. At float level.
There is a downside, though. But it's difficult to pinpoint. Firstly, I've fitted new tyres, so it might just be the extra tread, but I can feel the tread itself a bit more. More the point though, the drivetrain feels a little more.. apparent. I can really feel the chains (I have two on this child-back tandem). This too might not be the armour, but having swapped the wheel out and subsequently had the derailleur re-aligned. Still, having just lubricated it all, I've never experienced this before.

A bike always feels slightly different when It's put back together. Fact is it runs fine, rides fine, handles as well as it ever has and I've no complaints - hopefully it will be a long time before my next update!
MikeyMK is offline  
Old 11-11-19, 05:59 AM
  #53  
dedhed
SE Wis
 
dedhed's Avatar
 
Join Date: Apr 2005
Location: Milwaukee, WI
Posts: 10,516

Bikes: '68 Raleigh Sprite, '02 Raleigh C500, '84 Raleigh Gran Prix, '91 Trek 400, 2013 Novara Randonee, 1990 Trek 970

Mentioned: 40 Post(s)
Tagged: 0 Thread(s)
Quoted: 2731 Post(s)
Liked 3,361 Times in 2,034 Posts
Originally Posted by 86az135i
IMO creating a non-pneumatic tire for cars is about the stupidest idea. Flats are very rare. And performance will only decrease and cost will increase with a solid wheel or tire.
It's not about flats on motor vehicles. It's about saving both sprung & unsprung weight.
dedhed is offline  
Old 11-13-19, 08:27 AM
  #54  
86az135i
Banned.
 
Join Date: Dec 2018
Location: Mesa, AZ
Posts: 154

Bikes: 1996 Cannondale R900, 2016 Trek Boone, 2005 Giant Yukon

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 584 Post(s)
Liked 66 Times in 54 Posts
Originally Posted by dedhed
It's not about flats on motor vehicles. It's about saving both sprung & unsprung weight.
If it's about saving un-sprung weight then pneumatic is your best option. A compressible fluid such as air is a lot lighter then trying to get a non-compressible solid to flex and behave in a similar manner.
86az135i is offline  
Old 11-13-19, 10:43 AM
  #55  
dedhed
SE Wis
 
dedhed's Avatar
 
Join Date: Apr 2005
Location: Milwaukee, WI
Posts: 10,516

Bikes: '68 Raleigh Sprite, '02 Raleigh C500, '84 Raleigh Gran Prix, '91 Trek 400, 2013 Novara Randonee, 1990 Trek 970

Mentioned: 40 Post(s)
Tagged: 0 Thread(s)
Quoted: 2731 Post(s)
Liked 3,361 Times in 2,034 Posts
Originally Posted by 86az135i
If it's about saving un-sprung weight then pneumatic is your best option. A compressible fluid such as air is a lot lighter then trying to get a non-compressible solid to flex and behave in a similar manner.
"Because overall weight is reduced, fuel consumption is lower and handling has the potential to be improved as unsprung weight is removed from each corner."

https://www.wired.com/2013/09/hankook-i-flex/
dedhed is offline  
Old 11-13-19, 11:28 AM
  #56  
BlazingPedals
Senior Member
 
BlazingPedals's Avatar
 
Join Date: Dec 2004
Location: Middle of da Mitten
Posts: 12,474

Bikes: Trek 7500, RANS V-Rex, Optima Baron, Velokraft NoCom, M-5 Carbon Highracer, Catrike Speed

Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 1511 Post(s)
Liked 733 Times in 454 Posts
There are probably weight savings possible by making the wheel itself a wear item; but I still don't see a combined wheel/tire as a good idea.
BlazingPedals is offline  
Old 11-13-19, 11:54 AM
  #57  
ksryder
Senior Member
 
Join Date: May 2014
Posts: 2,549

Bikes: yes

Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 1281 Post(s)
Liked 643 Times in 329 Posts
Taking this thread seriously for a second, I remember these making the rounds at some trade shows a few years ago. Looks like the idea is still kicking but I have yet to see any in the real world.

https://bikerumor.com/2019/01/22/new...to-bikes-more/

And:

ksryder is offline  
Old 11-13-19, 09:46 PM
  #58  
MikeyMK
Cycleway town
 
MikeyMK's Avatar
 
Join Date: Jul 2014
Location: Milton Keynes, England
Posts: 1,402

Bikes: 2.6kw GT LTS e-tandem, 250w Voodoo, 250w solar recumbent trike, 3-speed shopper, Merlin ol/skl mtb, 80cc Ellswick

Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 569 Post(s)
Liked 169 Times in 117 Posts
When an impact strikes a pneumatic tyre, the energy is absorbed by the entire tyre; as the affected area deforms, the air pressure is raised throughout. The spring-rate is shared all the way around.

Every non-pneumatic tyre I've seen fails to utilise such a strength. The affected area alone has to dampen the impact.

I really can't see anything working like a pneumatic tyre until it's able to spread the energy like a pneumatic tyre.
MikeyMK is offline  
Old 11-14-19, 07:03 AM
  #59  
BlazingPedals
Senior Member
 
BlazingPedals's Avatar
 
Join Date: Dec 2004
Location: Middle of da Mitten
Posts: 12,474

Bikes: Trek 7500, RANS V-Rex, Optima Baron, Velokraft NoCom, M-5 Carbon Highracer, Catrike Speed

Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 1511 Post(s)
Liked 733 Times in 454 Posts
Originally Posted by MikeyMK
When an impact strikes a pneumatic tyre, the energy is absorbed by the entire tyre; as the affected area deforms, the air pressure is raised throughout. The spring-rate is shared all the way around.
Right. And as a result, air-free tires are much harder on rims. I remember a few reports of converts breaking their rims and then treating it as a coincidence. Nope, it was caused by the tire.
BlazingPedals is offline  
Old 11-14-19, 08:58 AM
  #60  
86az135i
Banned.
 
Join Date: Dec 2018
Location: Mesa, AZ
Posts: 154

Bikes: 1996 Cannondale R900, 2016 Trek Boone, 2005 Giant Yukon

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 584 Post(s)
Liked 66 Times in 54 Posts
Originally Posted by dedhed
"Because overall weight is reduced, fuel consumption is lower and handling has the potential to be improved as unsprung weight is removed from each corner."

https://www.wired.com/2013/09/hankook-i-flex/
Wow....much data...such truth.

BTW this article is over 6 years old. The reason you still don't see non-pnuematics is because you're fighting against physics. You are trying to make a non-compressible, heavy thing be a compressible, light thing. If non-pneumatics were so amazing, so revolutionary. They would be here today and not be a thing of yester-century.

Maybe I'm wrong. But I doubt I'll be wrong anytime soon.

Last edited by 86az135i; 11-14-19 at 09:05 AM.
86az135i is offline  
Old 11-17-19, 10:31 PM
  #61  
maallyn
Junior Member
Thread Starter
 
Join Date: Aug 2017
Posts: 84
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 21 Post(s)
Likes: 0
Liked 12 Times in 10 Posts
Thank you all!

Folks:

Sorry for being invisible for a long time. Some serious stuff came up and I did let things slide. I am happy, though, in seeing what alternatives are out there and what may be coming down the road in the future.

I do have to accept that this is a challenging problem because of different riding conditions and being able to use different air pressures.

I am a bit excited at the possibility of better conform and stretch technologies that can withstand a pin/tack/broken glass/whatever without getting punctured. Perhaps would this be the answer, along with steel belts or radials?

I currently have schwabbles and I have been having problems with broken glass working its way through the tread (not the sides) and causing flats. I average (here in Bellingham, Washington) about three flats per year; all were broken glass that has pierced the center of the tread and into the tube.

Mark Allyn
Bellingham, Washington
maallyn is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.