Top 5 most fuel efficient tires (Lowest Rolling resistance: LRR)

[Vekke]

Trocken=drygrip
nass= wetgrip
gerauch=noise
krafttorstverbrauch= fuel consumption
verchsleiss= wear


In all sectors the "better" value is the lower number so 0,5 is the best grade 5 the worst.

One correction to my previous comment: Dunlop was bad in wear (I looked one line too low). so choice would be between Michelin energy saver or goodyear duragrip. Duragrip is maybe little cheaper . Thanks for that link there were a test also in size 205/55/R16 W try to find that also if you have time. I have only the magazine in finnish...

[Bicycle Bob]

New Hankook tire gives 5% better mileage:
Hankook's enfren low rolling-resistance tires deliver 5 percent fuel saving

[Vekke]

Goodyear has also new LRR tire Materials - Automotive Engineering International Online Should be cheaper than other eco tires :/.

[ESmooth]

$071 0.0062 Bridgestone/Firestone B381 P185/70R14: (another report said 0.00615)

I am listing only this tire for this size since its the absolute best LRR tire out of ANY SIZE and there is NO EXCUSE not to get it as it will save you more money over its lifetime than it would cost to even ship them over (if they are not available in your area).

Hopefully this commentary is still true as I just ordered a set to replace my worn and now nail-damaged Kumho PowerStars.

Im averaging about 36MPG and am looking forward to seeing some improvements.

[Ernie Rogers]

I am very uncomfortable with the idea that one size of tire has a lower rolling resistance than another. Is it the test standard to load a tire according to its load rating? Then, a larger tire is tested at a higher load.

In a buying decision, if tire size is considered, a larger diameter tire should be expected to provide better fuel economy for two reasons-- (1) it lowers engine RPM, and (2) for a given load, a larger diameter lowers Crr at least in theory.

Ernie Rogers

Originally Posted by ESmooth

"$071 0.0062 Bridgestone/Firestone B381 P185/70R14: (another report said 0.00615)

I am listing only this tire for this size since its the absolute best LRR tire out of ANY SIZE and there is NO EXCUSE not to get it as it will save you more money over its lifetime than it would cost to even ship them over (if they are not available in your area)."

Hopefully this commentary is still true as I just ordered a set to replace my worn and now nail-damaged Kumho PowerStars.

Im averaging about 36MPG and am looking forward to seeing some improvements.

[CapriRacer]

Originally Posted by Ernie Rogers

I am very uncomfortable with the idea that one size of tire has a lower rolling resistance than another. Is it the test standard to load a tire according to its load rating?

..........

Yes, but the results can either be reported by Rolling Resistance (in pounds) or by Rolling Resistance Coefficient (RRC, = RR / Load, dimensionless). In this case it's RRC.

So, an otherwise identical, but larger tire with have a higher RR , but it's RRC will be ever so slightly less.

Originally Posted by Ernie Rogers

......

Then, a larger tire is tested at a higher load.

.............

Yes

Originally Posted by Ernie Rogers

.........

In a buying decision, if tire size is considered, a larger diameter tire should be expected to provide better fuel economy for two reasons-- (1) it lowers engine RPM, and (2) for a given load, a larger diameter lowers Crr at least in theory.

Ernie Rogers

There are a couple of confusing factors here.

When I use the term "Larger" I mean load carrying capacity. Larger capacity tires have more RR and slightly less RRC - in otherwise identical tires.

However, larger diameter tires .... well ........ they tend to be also larger load carrying capacity, which confuses the issue on RR and RRC, but it appears that load carrying capacity is what is driving the RR and RRC values for otherwise identical tires. So I think we ought to stay away from the diameter issue as "larger diameter" tires MIGHT not have better RR or RRC. But clearly, larger diameter tires will have an effect on the overall gear ratio of the drivetrain - and for fuel economy, that is usually a good thing.

BUT

It can be quite difficult to determine if tires are "otherwise identical". OE tires are designed to the specs of the vehicle manufacturer - and among those specs is usually a maximum RR value.

But different sized tires will go to different vehicles and the tire specs for each vehicle will be different. So a Goodstone FireEagle on a Chevy Pony will probably not be identical to a slightly larger Goodstone FireEagle on a Ford Antelope. Selecting one of these based on the test results of the other may or may not given the desired results.

[tjts1]

This is all very interesting and what not but traction and safety are far more important to me than rolling resistance. This is one area I'm not going to compromise. I found a set of "195/65-14 Falken Sincera Tires" for $204 shipped to my door. I think I'm going to pull the trigger on this.

[ESmooth]

Well the B381s are OEM on Honda Insights and Civic Hybrids so Im not too worried.

I got the tires installed last night and so far so good. Just topped off on fuel to see if I can notice any improvements with this first tank as the tires start to break in. They certianly are smoother and quieter than the Kumhos i took off but they were pretty worn out.

[RobertSmalls]

The Potenza RE92 165/65R14 are rated for use on 14" rims, 4.0" to 6.0" wide. Stock rims on the Insight are 14"x5.5", and the spare tire has an alloy wheel, 14"x4.0". What would happen if I got four spare wheels and mounted real tires on them?

I reckon the answer would be "larger circumferance, smaller contact patch, less traction". But would the differences be noticeable, and would there be less sidewall flexion and rolling resistance?

[CapriRacer]

Originally Posted by RobertSmalls

The Potenza RE92 165/65R14 are rated for use on 14" rims, 4.0" to 6.0" wide. Stock rims on the Insight are 14"x5.5", and the spare tire has an alloy wheel, 14"x4.0". What would happen if I got four spare wheels and mounted real tires on them?

I reckon the answer would be "larger circumferance, smaller contact patch, less traction". But would the differences be noticeable, and would there be less sidewall flexion and rolling resistance?

Using a narrow rim tends to arch the tread surface of the tire. The published allowable rim width range keeps the arching to a minimum.

But it is a misconception that the sidewall is what controls the amount of flex. What is really resisting the load is mostly in the tread area - and in particular the steel belts. The sidewall flexes, but doesn't contribute much to resisting the load.

So using a rim on the narrow end of the range isn't going to change the amount of RR, becuase the same amount of "tread" (both the tread itself and the steel belts) are being engaged.

What might happen is that the pressure distribution on the tread surface will change to more pressure applied to the center - and this might result in some wear issues. But the big thing would be the tire would become more sensitive to road surface irregularities - it will try to follow the grooves and the ruts in the pavement.

Plus many spare rims are built thinner - and that makes them less durable, prone to cracking.