Wheels & Tires

[2.ooohhh]

I'll have no part of run flats, in fact they are the first thing I've removed from a few BMWs that came with them originally. The sidewalls have to be so stiff for you to be able to drive on them "flat" that they ride and handle terribly compared to traditional non run flat tires.

 

[eddie66]

When I watch the commercial for those "run flat" tires, I wonder what is the logic behind them? It seems to me, if they run flat, wouldn't you not be aware you had a flat when you puncture one until you traveled an additional 50 miles, possibly into the middle of nowhere? If I had a flat, I would prefer to know it when it happened. Do you get some kind of pre notification to let you know when it was punctured, or when it will go flat? Other wise, what was the point? Having never had these tires, I just don't get the concept.

 

[CrimsonEclipse]

When I watch the commercial for those "run flat" tires, I wonder what is the logic behind them? It seems to me, if they run flat, wouldn't you not be aware you had a flat when you puncture one until you traveled an additional 50 miles, possibly into the middle of nowhere? If I had a flat, I would prefer to know it when it happened. Do you get some kind of pre notification to let you know when it was punctured, or when it will go flat? Other wise, what was the point? Having never had these tires, I just don't get the concept.

The idea is to allow a driver to continue to drive out of a bad neighbor hood or unsafe road to a repair station.
It adds a false sense of security.

On FB, ElioMotors said rear tire will be wider. That's all I know.

I saw that post too. So that solves the tire rotation question. I wonder why. Over steer? Weight?

 

[RK2112]

When I watch the commercial for those "run flat" tires, I wonder what is the logic behind them? It seems to me, if they run flat, wouldn't you not be aware you had a flat when you puncture one until you traveled an additional 50 miles, possibly into the middle of nowhere? If I had a flat, I would prefer to know it when it happened. Do you get some kind of pre notification to let you know when it was punctured, or when it will go flat? Other wise, what was the point? Having never had these tires, I just don't get the concept.

Usually run flat tires are used in conjunction with a TPMS system.

 

[karl]

Modern tires are right up there with computer control as the main factors our vehicles are so much better today. We could make cars that could go fast but there was a reason the cars in the twenties carried so many spare tires. They needed them. Tires would just self destruct with often fatal results. http://en.wikipedia.org/wiki/Bernd_Rosemeyer

The mom and pop radials you can buy at any tire store today are better than the best race rubber you could buy just a few decades ago.

 

[Elio Amazed]

Yes, there would be an issue if you were cruising along a back road at 0 to 10 mph, with gun in hand. I don't think the DNR would consider it 'Deer Shinning', ("Spotlighting"), when you're cruising along at 50 to 70 mph on a main road. If they did you would beat the charge in court plus, I'm sure you would get a chuckle out of the judge.

Actually, though a lot of bicycle riders use head/helmet mounted lights all the time, I know of no such devices that are currently DOT approved for that type of use in or on motor vehicles while they are operating on a public motorway.

Most of us out here that use auxillary lighting not approved by the DOT for road illumination or signaling while operating a motor vehicle on a public motorway are in violation of state and federal law.

In addition, most of us who have changed out or modified our exhaust system on our MC or car from the orginal equipment that was designed and DOT approved for that particular vehicle are in violation of state and federal law.

If such unapproved added lighting is wired up so it is on when the vehicle and/or original lighting is operating and it does not have it's own on/off switch, the state inspection station is technically supposed to fail the vehicle for inspection.

The same is true for exhaust modification.

It is, however, one of those sets of laws that's usually overlooked by LEOs and the state inspection systems (except for removing cat converters).

My aftermarket Jardine rumblers are so loud that I have to wear earplugs with my 3/4 (and even my full-face modular) so I don't damage my hearing when I crank the beast past 55mph.

But I'm heard when not seen.

My aux 325-lumen (non-DOT) LED bullets are aimed downward enough to not shine their full punch into oncoming traffic.

Not only am I able see more, but I'm seen sooner.

In many areas, any "decorative" LED lighting on a motor vehicle is illegal. In most areas, using certain colors of illumination on a vehicle is illegal.
In almost all areas using "decorative" light systems that cycle through on/off or color changes is illegal.

That being said, if you do make it to court for something extremely over line like wearing a 200 lumen light on your head while operating a MOTOR vehicle on a public motorway, DO NOT expect a judge to be yuckin' it up with you.

 

[eddie66]

Actually, though a lot of bicycle riders use head/helmet mounted lights all the time, I know of no such devices that are currently DOT approved for that type of use in or on motor vehicles while they are operating on a public motorway.

Most of us out here that use auxillary lighting not approved by the DOT for road illumination or signaling while operating a motor vehicle on a public motorway are in violation of state and federal law.

In addition, most of us who have changed out or modified our exhaust system on our MC or car from the orginal equipment that was designed and DOT approved for that particular vehicle are in violation of state and federal law.

If such unapproved added lighting is wired up so it is on when the vehicle and/or original lighting is operating and it does not have it's own on/off switch, the state inspection station is technically supposed to fail the vehicle for inspection.

The same is true for exhaust modification.

It is, however, one of those sets of laws that's usually overlooked by LEOs and the state inspection systems (except for removing cat converters).

My aftermarket Jardine rumblers are so loud that I have to wear earplugs with my 3/4 (and even my full-face modular) so I don't damage my hearing when I crank the beast past 55mph.

But I'm heard when not seen.

My aux 325-lumen (non-DOT) LED bullets are aimed downward enough to not shine their full punch into oncoming traffic.

Not only am I able see more, but I'm seen sooner.

In many areas, any "decorative" LED lighting on a motor vehicle is illegal. In most areas, using certain colors of illumination on a vehicle is illegal.
In almost all areas using "decorative" light systems that cycle through on/off or color changes is illegal.

That being said, if you do make it to court for something extremely over line like wearing a 200 lumen light on your head while operating a MOTOR vehicle on a public motorway, DO NOT expect a judge to be yuckin' it up with you.

I have several friends in law enforcement, and they will tell you they love to see vehicles with those neon licence plate frames. They are illegal, but they let them slide because they constitute "probable cause" for a future traffic stop. So if they want to stop that particular vehicle at a future time, they don't need a reason.

 

[Folks]

Actually, though a lot of bicycle riders use head/helmet mounted lights all the time, I know of no such devices that are currently DOT approved for that type of use in or on motor vehicles while they are operating on a public motorway.

Most of us out here that use auxillary lighting not approved by the DOT for road illumination or signaling while operating a motor vehicle on a public motorway are in violation of state and federal law.

In addition, most of us who have changed out or modified our exhaust system on our MC or car from the orginal equipment that was designed and DOT approved for that particular vehicle are in violation of state and federal law.

If such unapproved added lighting is wired up so it is on when the vehicle and/or original lighting is operating and it does not have it's own on/off switch, the state inspection station is technically supposed to fail the vehicle for inspection.

The same is true for exhaust modification.

It is, however, one of those sets of laws that's usually overlooked by LEOs and the state inspection systems (except for removing cat converters).

My aftermarket Jardine rumblers are so loud that I have to wear earplugs with my 3/4 (and even my full-face modular) so I don't damage my hearing when I crank the beast past 55mph.

But I'm heard when not seen.

My aux 325-lumen (non-DOT) LED bullets are aimed downward enough to not shine their full punch into oncoming traffic.

Not only am I able see more, but I'm seen sooner.

In many areas, any "decorative" LED lighting on a motor vehicle is illegal. In most areas, using certain colors of illumination on a vehicle is illegal.
In almost all areas using "decorative" light systems that cycle through on/off or color changes is illegal.

That being said, if you do make it to court for something extremely over line like wearing a 200 lumen light on your head while operating a MOTOR vehicle on a public motorway, DO NOT expect a judge to be yuckin' it up with you.

What kind of setup would you recommend to convince the DOT that I'm only hunting sachsquatch ?

 

[eddie66]

What kind of setup would you recommend to convince the DOT that I'm only hunting sachsquatch ?

eye level lasers that blind everyone for a three mile radius

 

[Snick]

If the Elio is to achieve its fuel economy goals, tires will have to be < 85mm average section width, give-or-take. For this vehicle, rolling resistance is greater than aerodynamic resistance for a 'mixed mode' and most highway driving cycles that most of us will use it for! Also, the tires will contribute to frontal area (adding aerodynamic form drag) and because airflow is so turbulent at exposed parts of tires it also increases the aerodynamic friction drag component.

So, engineering goals of good mpg almost dictate a narrow tire section width. For the light weight of the car--you also need a certain footprint loading. Optimal would be largest diameter rim that can practically fit on car (and with respect to suspension motion/travel) which is somewhere around 15" or 16" diameter in my guess. You also need high tire pressures and low Crr tire compounds (silica based)...probably psi in the range of 55-75 max for comfort and Crr of <0.077. My guess is the rear tire will have lower psi to preserve comfort--fronts don't matter as much because suspension design really helps isolate shocks from occupants (and can be softly sprung without sacrificing much if any real world at-the-limit handling), but rear tire is much harder to isolate vertical shock motion from occupant feel.

My guesses:

15" diameters all around. Maybe 16" or larger for rear, probably not.
fronts: 85mm or 90mm section widths; recommended pressure range from 60-77psi depending on winter/summer.
rear: 90mm-105mm section width; recommended pressure range from 50-68 psi depending on winter/summer.

Crr for compound for all tires will be <0.077.

Also, I think the designers may have to compromise on aesthetics and fair all three tires all the way down to 1.5" off the ground. Otherwise that rear tire will add measurable form and friction drag, and car will struggle to achieve 84mpg at realistic freeway speeds, which is what drivers expect from claims, not to have to travel at 65mph top speed to get the 84mpg. I contend most people will expect to get 84mpg going 75-80 mph, which is substantially more challenging.