Dispatches from District 48
Maybe I am missing something, but "friction-reduced" tires seem to be going in the wrong direction. Hopefully friction-reduced brake pads or inflation-reduced airbags are not next.
The ideal is, I think, a tire with a ROLLING resistance as low as possible, but a much higher friction when you want to apply some delta-v.
I know that underinflated tires dissipate energy because you're continuously compressing and then stretching the sidewall, all to no effect.
So there ARE some optimizations that can be made.
You'd ideally want a tire that had zero rolling reisistance while driving, but high rolling resistance while braking, and high friction all the time.
Nothing new here. Always been the case. Those 60K mi, long lasting tires got that way w/ low friction. It's a trade off.
When I was working with cars a lot, I was told several times that tires are the most primitive technology on vehicles today. I guess there's only so much you can do with rubber, steel and nylon cords.
this is what they put on the tesla roadster to get it's range up. it's also how they managed to take the lotus elise chassis, one of the best handling cars in the world, and make it corner like a pickup truck.
eco-weenies can wreck anything.
Today, OTOH, I saw organic balsamic vinegar for less than "conventional." Maybe a demand response?
Frictionless tires are actually pretty nifty. We are talking rolling resistance and not sticking resistance here. I don't believe that car tires are the most uninovative part of a car. It's just that the advancements are in detail: consumption reduction, NVH improvements and wear resistance are just 3 topics I can think about, where cars got better and cheaper.
Imo the electric cable system and connector layout is the least innovative part. I mean with all the modern appliances, we still only have 1 or 2 electric sources per car...
This is all a result of brain reduced politicians and bureaucrats.
You know what this means. Speed limits will have to be reduced! It is the ONLY option, since going back to the safer tires is not possible.
Driving is getting safer; perhaps it's actually time to reevaluate the tradeoff between safety and fuel efficiency.
Well, I hope they don't go to far or you'll just be spinning your wheels.
Reduced friction = reduced traction, there is no magic here to replace the laws of physics. The 2-3% increase in mileage they are claiming is not a very good trade off when you consider the reduced traction. The assumption is late model cars can do with less traction due to traction control, ABS, etc. that can compensate for a less sticky tire. If you are this concerned about mileage or the environment, you really shouldn't when you consider the average car today gets 4x the mileage, pollutes 50% less than cars of 40 years ago.
You can see a reduction in rolling energy losses at the same time as you get an improvement in handling--at least if you're starting from a vanilla sedan tires. It just costs real money, because you get a lot of it from increased sidewall stiffness.
I generally buy "all weather performance" tires, and they cost a 50-100% increment over basic tires, but they handle better, are generally a little quieter and get fractionally better gas millage.
Note, however, that if you really push for low rolling resistance you have to give up handling and noise eventually, and the stock tires on most of the hybrids have gone pretty far down that road in search of that magical MPH figure.
It's like a lot of things in engineering, there are a bunch of metrics here---cost, handling, rolling resistance, noise, durability---and a complicated set of tradeoffs available. Do your research and pick the ones that meet your needs.
Tires in general are notably better and cheaper than when I started driving in the '80s.
They always want something for nothing. Can't have it.
The low rolling resistance tires I had on my Camry hybrid added 3 to 5 mpg to the average mileage. But they were terrible in the snow. I switched over to standard tires this time around. I may switch over to something else next time I replace my tires, but that's another 30K miles away.