New Light Weight Thermoplastic Wheels For Smart

[bilgladstone]

Wow! What a great wheel! I wonder how cold weather climates will affect it?

The plastic wheel rims are made of Ultramid® Structure, an innovative high-performance plastic. It significantly reduces vehicle weight, lowers emissions and extends range.

Ultramid® Structure has reinforcing glass fibers added to make the plastic robust and improve its mechanical properties even more. It makes the wheel rims durable enough for continuous use long-term use.

Ultramid® Structure is suitable for any application requiring high strength plus lightweight construction. This is the case in many other areas as well as the car industry.

Bil Edited March 28, 2012 by bilgladstone

[strawboss]

I'm interested! the reason (other than price) that I avoid the aluminum alloy rims is that they tend to leak air at the bead....a good technician can reduce this tendency by using among other things latex paint at the bead rim junction, but these look like winners if like you say they pass the -40 c test.If the price is right .....

[Alex]

That would be the "pothole at -40 test" you refer to, right?

[gordo.bernard]

BASF is behind this and not some wheel manufacturer, so it will be backed by intensive research for sure. Will brake cleaning and wheel cleaning chemicals and tire in a can inflators all be banned from getting near these? Will these degrade from sun exposure like you see unpainted black nylon door handles on older cars? Will all of the interlaced structural ribs that are found on the internal face and the external face as well as the inside section of the hoop collect dirt snow or ice and cause the wheel to become unbalanced? Will it handle the expansion pressures of melted snow freezing into ice? Are the quoted weight savings based on current metal rims or some innovative metal alternative that was perhaps not on the design table? Was the wheel cover part of the quoted weight savings or is it an integral part of the wheel that can't be customized? Most of all, will we be taking a risk when the fancy aftermarket lookalikes start rolling out of China?.

[MikeT]

BASF makes the crazing roofs of the 451, don't they?

[tolsen]

The plastic wheel is only 30% lighter than an aluminium wheel therefore about same weight as a steel wheel.

http://www.asminternational.org/portal/sit...000621e010aRCRD

A backwards step in my opinion potentially adding to motoring cost for the poor owner.

[bilgladstone]

So are the smart steel wheels 30% lighter than the alloys? I haven't seen published weights yet. Not that I don't believe it, just asking for numbers.Bil

[lebikerboy]

The plastic wheel is only 30% lighter than an aluminium wheel therefore about same weight as a steel wheel.http://www.asminternational.org/portal/sit...000621e010aRCRDA backwards step in my opinion potentially adding to motoring cost for the poor owner.

Nowhere in that article does it say the thermoplastic wheel weighs the same as a steel wheel...Nor have I ever seen published weights which state that there is a 30% difference betweenOEM steel wheels and OEM alloys. Edited March 28, 2012 by lebikerboy

[strawboss]

That would be the "pothole at -40 test" you refer to, right?

You flunked that one too eh? I studied & everything....

[tolsen]

Nowhere in that article does it say the thermoplastic wheel weighs the same as a steel wheel...Nor have I ever seen published weights which state that there is a 30% difference betweenOEM steel wheels and OEM alloys.

Smart steel rims are approximately 30% lighter than Smart aluminium rims.

[lebikerboy]

Show me...

[MikeT]

It is a pretty broad generalisation, considering the wide variety of OE alloys on the smart.I weighed my naked strikelines years ago and the results are posted here.

[strawboss]

My reaction was "no way that steel can be lighter..... aluminum alloys are always lighter" then I went Googling

The first paragraph under the heading of "characteristics".

http://en.wikipedia.org/wiki/Alloy_wheel

(Edited for clarity)

Edited March 29, 2012 by strawboss

[tolsen]

Show me...

Go weigh some rims. Allow rims are primarily designed for looks, not for strength and low weight. Edited March 29, 2012 by tolsen

[MikeT]

Oops, they weren't naked. Here are the figures with tires mounted:

strikeline, Front - 5J-15, with 175/55-15 Conti Eco Contact T Rated: 12.5 kg (new tires)

strikeline, Rear - 6.5J-15, with 195/50-15 Conti Premium Contact T Rated: 14.5 kg (new tires)

jetline, Front - 4J-15, with 145/65-15 Conti Eco Contact T Rated: 11 kg (tire with 42,000 km of wear)

jetline, Rear - 5.5J-15, with 175/55-15 Conti Eco Contact T Rated: 14.0 kg (tire with 9000 km of wear)

Now, someone go weigh some steelies w/tires and we've got a thread going.

[tolsen]

I can already see a trend which is pretty well explained on Wikipedia (see link already provided by strawboss, heading "Aftermarket wheels":

Many people may think that large wheels automatically result in increased performance, handling and suspension, yet Car and Driver performed a test of different sized wheels from 15" to 19" all outfitted with the same make and model of tires and showed that both 0-60 times and fuel economy were reduced with larger wheels. They also noted that ride comfort and noise were negatively affected by the larger massively heavy wheels.

[MikeT]

So who is going to weigh their steelies?I enjoy the extra grip with my wide ones and gladly accept the 0.2 L/100 km hit (it's still under 4 on the older car)

[bilgladstone]

I'll do a weigh-up when I get ready to switch to summer tires.B

[MikeT]

You have the wide boys though, right? At least on the front. I could weigh my winters on steelies soon...like in a couple of weeks.

[bilgladstone]

I can weigh the J5 Roadster steel with summer 175 tires mounted.And I can weigh the two sizes of oem fortwo steelies with 145 & 175 snow tires mounted.This is the problem with weighing with mounted rubber. What make/size of tire? Winter chunkies, or summers? How much tread is there on each? It is not a straight apple:apple comparison. It puzzles me that this is such a common question, even looking in forums on most other makes of car. Everyone is asking how much oem steels weigh versus oem alloys. Why is it so hard to find a resource for each marque stating standard weights? Could it be that if consumers discovered that steel wheels were the same weight as - or lighter than - those fancy and expensive alloys, contrary to the "common wisdom" that alloys MUST be lighter, that up-sell sales would decrease?B

Edited March 29, 2012 by bilgladstone

[MikeT]

Could be; steel is OK by me. The roadster wheels with wide rubber look OK and give the good handling I crave. Light wheels are important for agility in acceleration - cycling teaches you that!

[bilgladstone]

Yes, I remember we tried a bunch of wheels but the scale was way inaccurate. And I do kind of remember we were disappointed that the steels and alloys didn't seem to be much different.But let's try again, since you have a bunch of wheels not on cars... if you can get hold of a better scale.B

[strawboss]

Even with supposedly lighter weight being a factor I never owned or bought aluminum alloy rims for a few reasons, their relative fragility,higher cost,and a tendency to lose air.When I got a new set of tires for my pickup my steel rims were looking a bit ragged so I asked the clerk at the counter if the difficulties with "alloy" rims were finally fixed after four decades, he just rolled his eyes & shook his head... And he sells them...

[strawboss]

Further to tolsen's post, as most regulars here are more mechanically inclined than average I'm sure that this isn't news to some but a larger diameter rim/wheel effectively increases the overall apparent gear ratio of every gear, making a car like a smart even more of a dog pulling away from a dead stop and probably increasing wear on the clutch.My Tacoma has a "bull" first gear (in high range) so it will accept larger diameter tires/rims but I value torque more that all out top speed, sometimes I pull away in 2nd 'cause I'm too lazy to shift.

[MikeT]

Never had a leaky alloy in my life: if they are powder coated as most smart wheels are, they won't leak.Overall diameters aren't usually the main issue, rather it is unsprung mass and rotating mass. Both of those will dull acceleration quite a bit, nd make the suspension have a greater challenge controlling the car. That's why I stick with "modest" wider alloy wheels.