Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Size of the tire - are smaller (narrower) tires really better?

BennyL · 08-27-2012, 07:07 PM

Hi,

i have an question which i have a long time in my head:

Often ist said that smaller tires (not smaller amount) are better to save gas.

But i read in a forum for racingbikes (cycle) that tires which are very narrow have a higher rolling resistance than wider tires at same inflation. This is because of the friction inside the small tire. A wider tire has less deformation at same pressure as a narrow tire.

In wikipedia i read that a tire of a normal car has a rolling resistance (Cr) of 0,011–0,015, ad a much more bigger tire of a big truck (LKW) has only 0,006–0,010 on same track.

I´m planning to buy new summer tires with rims for my golf, and can´t decide between 175/80R14 and 195/65R15. With this information the 195/65R15 should have a smaller rolling resistance, because there is more air inside, and with its bigger wide the deformation should be less than in the narrow tire with high rubber.

Has anyone some information about this things? Could it be that the most narrow tire isn´t the best in rolling resistance?

The diameter of my tires has to be the same because of german laws and police...

Kind regards,

Benny

08-27-2012, 07:07 PM	#1 (permalink)
BennyL German Hypermiler Join Date: Aug 2012 Location: Springe, Germany Posts: 5 Thanks: 0 Thanked 0 Times in 0 Posts	Size of the tire - are smaller (narrower) tires really better? Hi, i have an question which i have a long time in my head: Often ist said that smaller tires (not smaller amount) are better to save gas. But i read in a forum for racingbikes (cycle) that tires which are very narrow have a higher rolling resistance than wider tires at same inflation. This is because of the friction inside the small tire. A wider tire has less deformation at same pressure as a narrow tire. In wikipedia i read that a tire of a normal car has a rolling resistance (Cr) of 0,011–0,015, ad a much more bigger tire of a big truck (LKW) has only 0,006–0,010 on same track. I´m planning to buy new summer tires with rims for my golf, and can´t decide between 175/80R14 and 195/65R15. With this information the 195/65R15 should have a smaller rolling resistance, because there is more air inside, and with its bigger wide the deformation should be less than in the narrow tire with high rubber. Has anyone some information about this things? Could it be that the most narrow tire isn´t the best in rolling resistance? The diameter of my tires has to be the same because of german laws and police... Kind regards, Benny __________________ ecomodding in germany, with prices of more than 8$ per gallon....