# Low Rolling Resistance Tires



## xrotaryguy (Jul 26, 2007)

The Potenza RE92's in the 165/65R14 and 175/65R14 
sizes are LRR, but there are no numbers in the green 
seal report. The 165 is the OEM Honda Insight tire, 
the 175 is the OEM Prius tire. The 175 size also comes 
in an XL or extra load rated tire so that might be the 
thing to get for a conversion.

The 2004-2007 Prius comes with Goodyear Integrity 
185/65R15 tires "made in Japan". A tire store Goodyear Integrity 
185/65R15 is "made in USA" and is not the same tire. It may have 
improved life, quieter, handles better, etc. -- but it doesn't have the 
same low rolling resistance.


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## xrotaryguy (Jul 26, 2007)

Here is a publication that lists LRR tires.


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## rbgrn (Jul 24, 2007)

Let me guess... Low rolling resistance = Less traction?


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## Solar Trucker (Jul 26, 2007)

The trade off for LRR tires is usually tread life not traction.


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## Dan Frederiksen (Jul 26, 2007)

michelin seems to still be working on their tweel thing and I saw a quote that said it was only 5% the roll resistance of a normal tire 

http://www.michelinman.com/difference/releases/pressrelease01102005a.html 

really disgusting line at the end of this though: 
http://youtube.com/watch?v=pcdmH_hVWBY 

'in 10-15 years' 

so we'll probably never get them. (they've been working on them since 95 already) 

http://youtube.com/watch?v=fqRJ9GfIJtI


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## xrotaryguy (Jul 26, 2007)

I doubt that LRR tires will give the same kind of traction that a nice high performance sports car tire will give you. You should see the terrible reviews that the Prius' LRR tires get on the Tire Rack's web site.



thetirerack said:


> I am amazed that companies like Toyota and Honda are putting these tires on their new cars. The tread life is horrible and the traction is well below any other tire I have used. These have to be the absolute worst tires I have ever used.
> -- _Review Submitted_ *2007-07-05 *





thetirerack said:


> Perhaps the worst tires I have ever driven on. These came new on my 2006 Pilot- I drove them for 10k white knucked miles before I replaced them with Michelin Cross Terrains. These tires are borderline dangerous on a Pilot in the rain. I became very familiar with the ABS and Traction control lights. The Goodyears hydroplane at the slightest assemblance of a puddle and would spin even at stop lights when we crossed the white line under modest throttle. We replace the tires showing NO wear at 10k with Cross Terrains- the difference is UNBELIEVABLE. Anyone who says they would by this tire again either workes for Goodyear or has never driven on a quality tire. I reterate- these are the WORST tires I have EVER driven on.
> -- _Review Submitted_ *2007-07-04*


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## Mr. Sharkey (Jul 26, 2007)

Although it doesn't pertain to anything you can buy today, my experience with Goodyear Invicta GLR 175/70-13's on my Rabbit is that they don't have much in the way of traction, and I wore the first set out at 10k miles. When that set got worn down to the bars, they became ~seriously~ dangerous on wet pavement, starting, stopping, and cornering all went out the window toward the end of their useful life.

So why did I put a second set on my EV? First of all, I bought them at a flea market for $75 for the set, still mounted on the OEM Honda wheels, and 99% tread. Second, they really do help the EV feel more willing to accelerate, and lowered the current draw at any speed significantly. I conversed with Bill Egan from Goodyear, and his advice was to pump them up to 50-55 PSI for best results.

My ICE Rabbit has a set of Michelin Pilot Exalto A/S 195/60-14 performance tires, and I can't say where the traction limit is because I haven't had enough nerve to throw the car around hard enough to find it. No idea what they would be like on the EV, though.


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## xrotaryguy (Jul 26, 2007)

There certainly seems to be a trade off between traction and rolling resistance. Oh well, no biggy. All in the name of better EV efficiency. Actually, 10,000 miles on a set of tires doesn't seem all that bad to me. I wore out a set of tires about once a year with my 84 Rx7. Then again, I had a lot of fun with that car


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## KiwiEV (Jul 26, 2007)

So for those of us who can't get and/or afford LRR tyres for various reasons, what's the next best thing?
Thinner tyres such as 165's instead of 185's? Or perhaps finding good second hand tyres that have an older, harder tread? Maybe both? 
To be honest, although it rains here a lot, a loss of traction upon take-off from the lights could be a good thing if you're looking to show off a little.

Not a good thing going around a corner though. Trade offs trade offs trade offs.


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## xrotaryguy (Jul 26, 2007)

There is a good conversation on this very subject in the EDVL section. I think it is in several threads. I guess the EDVL guys keep changing the subject. Anyway, the biggest things seems to be side wall flex, or should I say side wall compression. A tire will flatten on the bottom to some extent, so the side wall will "flex". It seems to me that most side LRR tires have a pretty high max pressure to minimize this side wall flex. Also, any kind of winter tire or aggressive tread will kill a tire's efficiency. I would tend to side with KiwiEV about skinnier tires having lower rolling resistance than wider tires, but remember, if the tire's maximum pressure is not high enough, then the side wall will flex excessively and rolling resistance will increase. Some of the LRR tires on the list are not too expensive. Perhaps a person could even find a used set with low miles on them for a reasonable price.


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