Video Exclusives

Michelin connected tires


The OEM has introduced a connected tire in motorsport, which enables drivers to monitor and control tire temperature and pressure in real time.

Click here to watch the video

Proving ground expansion


Millbrook is expanding its Test World facility in Finland...

Click here to watch the video

A day in the life of...


This short clip provides a glimpse into what's it like to be a Goodyear test driver

Click here to watch the video

Can you name this young Scottish visionary engineer who invented the pneumatic tire, decades before John Boyd Dunlop made a commercial success of it?

Web Exclusive Articles

« back to listing

Yokohama launches revolutionary concept tire

Incorporating new mixing technology, the BluEarth-air EF21 is rated AAA for rolling resistance and an A for wet grip – the highest graded on the market according to the Japanese tire label


Yokohama’s BluEarth-air EF21 tire incorporates the most advanced technologies and design techniques to achieve a significant reduction in weight compared to one of the company’s flagship passenger car tires.

Developed to mark Yokohama’s 100th anniversary, it was sold in Japan on a limited basis last year in size 205/55 R16 91V.

The BluEarth-air EF21 is rated AAA for rolling resistance and an A for wet grip – the highest graded on the market according to the Japanese tire label. This is thanks to a thin yet highly rigid structure, which, compared with the Advan dB V551, has resulted in a 25% reduction in the tire’s mass.

Tetsuo Ikegami, manager and head of testing group number one, says, “We have adopted an advanced lightweight design to reduce weight and the tire’s environmental impact through using less material, conserving resources and ultimately enabling a lower overall vehicle weight.”

Including market research, development, testing and production, the program for the BluEarth-air EF21 took nearly four years in total.

A new tread compound has also been developed. Weight reduction has been achieved mainly by thinning the rubber gauge of the tread and sidewall construction.

“We have even adopted a thinner tread gauge with shallower tire grooves,” notes Ikegami. ‘With the new compound we have achieved excellent wet grip and the same mileage performance as a conventional model.”

The compound is created using a new mixing method called advanced reaction technology. This technique refines the control over the reaction, and enables improved silica dispersibility – again improving wet performance.

During the program, physical testing was particularly important, mainly conducted at the company’s proving grounds in Ibaraki Prefecture and Hokkaido Island in Japan. Vehicles used included a Toyota Prius and a VW Golf.

Ikegami says there are currently no plans to expand the amount of sizes available.

February 1, 2018



Your email address:

Read Latest Issue

Read Latest Issue

Read Latest Issue

Web Exclusives

Completely truckworthy
Bridgestone America's director for commercial tire development, Mitchel Kritzell, gives an update on the SuperTruck II program
Read Now

Q&A: Sam Visaisouk, CEO, Tyromer
The Retread Tire Association (RTA) speaks with Tyromer CEO, Sam Visaisouk, about the testing of its new tire-derived polymer recycled rubber product in truck and passenger car tires
Read Now

Q&A: Chris Bitsakakis, AirBoss
The Retread Tire Association speaks with Chris Bitsakakis, chief operating officer and president of the rubber solutions division at AirBoss, about the partnership with Tyromer Inc. to develop a tire-derived polymer recycled rubber product
Read Now

Yokohama installs new ice test track
Operations are now in full swing at Yokohama’s new indoor ice test facility, located at the company’s Tire Test Center of Hokkaido in Asahikawa City, Japan
Read Now

Bridgestone Americas and Versalis in partnership
The two companies have revealed their plans to develop a technology package with the aim of commercializing guayule
Read Now

Supplier Spotlight

Supplier SpotlightWe are building a list of leading suppliers covering all aspects of the tire industry. Want to see your company included? Contact for more details.

Submit your industry opinion

Industry BlogDo you have an opinion you'd like to share with the tire technology community? We'd like to hear your views and opinions on the leading issues shaping the industry. Share your comments by sending up to 500 words to

Submit Your Recruitment Ad

Recruitment AdTo send us your recruitment advertising or to receive information on placing a banner please email