Go Back   EcoModder Forum > AltModding > Alternative Transportation
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 07-01-2013, 08:34 AM   #1 (permalink)
Master EcoModder
 
AndrzejM's Avatar
 
Join Date: Oct 2011
Location: Poland
Posts: 840

Berta - '97 BMW 318 tds Compact
90 day: 62.03 mpg (US)

Charlie - '07 Citroen C4 Grand Picasso Exclusive
90 day: 37.58 mpg (US)

Corsa - '05 Opel Corsa C
90 day: 53.22 mpg (US)
Thanks: 185
Thanked 167 Times in 117 Posts
Tire pressure vs rolling resistance - cycling in the rain

Hi Guys,

I've just found an article saying that decreasing tire pressure can actually lower the rolling resistance.
Tech-Talk-Tire-Pressure-in-the-Rain

What do you think of that?

__________________


Quote:
Gerhard Plattner: "The best attitude is to consider fuel saving a kind of sport. Everybody who has enough money for a strong car, can drive fast and hit the pedal. But saving fuel requires concentration, self-control and cleverness. It's a challenge with the nice effect of saving you money that you can use for other more important things."
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 07-01-2013, 09:55 AM   #2 (permalink)
Master EcoModder
 
Join Date: Aug 2010
Location: Philippines
Posts: 2,169
Thanks: 1,728
Thanked 582 Times in 399 Posts
Bicycle tires. whole 'nother ballgame compared to car tires. Very narrow tires... very light... very high pressure.

This probably explains it nicely:
http://janheine.wordpress.com/2012/0...ance-of-tires/

Quote:
Tires should not be tested without a rider on the bike. Most of the energy is lost in the rider, as vibrations cause friction in the body’s tissues (suspension losses). That is why testing in the lab can be misleading. In the lab, higher pressures roll significantly faster, but on the road, the suspension losses increase with higher pressures and cancel the advantage of the reduced tire deformation.

Last edited by niky; 07-01-2013 at 10:19 AM..
  Reply With Quote
The Following User Says Thank You to niky For This Useful Post:
California98Civic (07-01-2013)
Old 07-01-2013, 12:12 PM   #3 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 5,293

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 59.78 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 1,896
Thanked 1,600 Times in 1,087 Posts
This is a nice methodological point for all of us (riding bikes and driving cars) doing testing: "Did the results represent real differences in tire performance, or was there too much noise in the data? After all, even slight changes in rider position, a tiny gust of wind, or other factors might influence the results. To check this, Mark, who has a Ph.D. with a Minor in Statistics, did a sophisticated statistical analysis. He found that our results were “statistically significant.” (Basically, he compared the data from the three runs of the same tire with the data from different tires. The variations between runs with the same tire were much smaller than the variations between different tires.) This means we really did measure differences in tire performance. (Many studies skip this step, but it’s crucially important.)"
__________________


See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.

  Reply With Quote
Old 07-01-2013, 04:17 PM   #4 (permalink)
Master EcoModder
 
Join Date: Feb 2010
Location: Elmira, NY
Posts: 1,666
Thanks: 279
Thanked 293 Times in 245 Posts
Lennard Zinn is a recognized cycling expert and other noted authors such as Edmund Burke in "High Tech Cycling" deal with the high pressure racing tires used in competition. Tire internal deformation has a big effect on rolling resistance. What we are seeing now is the advent of tubeless tires in mountain bikes which have much less rolling resistance than tires with tubes. Selecting the tire for your riding application should include consideration for your weight and a tread that allows for water to move out of the tire patch area efficiently.

  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com