19" vs 21" Wheels Pros and Cons

[stopcrazypp]

Jury is out. The Model S is significantly heavier than the Roadster. The only significant difference for me was the difference between the Model S' 19" and 21" tires. The difference between the weight of the two vehicles could (stressing the could) mean that the Roadster and the 19" Model S are more identical than the Roadster and the 21" Model S.

Looking at the BMW 7 series forums (a car weighing 5000+lbs or 300-400lbs heavier than the 85kWh Model S) people have not experienced issues with bent wheels using essentially the same size 21" wheels with 35 aspect ratio (stock: 245/35R21 front, same as Model S, 285/30ZR21 rear).

22" and 25 or 30 aspect ratio has been a recipe for bend wheels though.
http://www.bimmerfest.com/forums/arc.../t-563320.html
http://www.bimmerfest.com/forums/arc.../t-514218.html

I don't think bent wheels should be a huge issue.

[SCW-Greg]

Given how Portlanders drive in the snow (poorly) I would just leave the Model S in the garage for the two snow days per year!

Yeah, hope I don't offend, but Real Oregonians drive in the snow like Real Californians drive in the rain! It's all good.

Californian transplants to here, are at least smart (terrified) enough when it snows, to stay home. Oregonians aren't. And I am one, but have learned, also have secret AWD weapon.

[SCW-Greg]

I know this has been re-hashed, but I'll add my own minor epiphany today.
I was worried that the Continental 21" wheels that will ship on my Model S Performance would not work will in the Oregon winters here. (read: rain, rain, and rain again, with about 2 weeks of snow).
I called a friend of mine, who teaches autocross and runs a custom auto shop in the area. He assured me it's not the size of the tires, its the specs, and how they channel away water that counts.

When I checked the specs, and compared them to my current tires (which I feel were a great improvement from my previous ones), the new 21" Continentals are rated even better for traction.
When I looked at the tread on the Continentals in the store, with another friend, without even asking him this friend (a well-experienced auto mechanic) told me those would work very well in the rain.

In short, I am no longer worried about running the Performance 21"s year round in Oregon. If winter gets gnarly, I'll just drive like they do in the Minnesota lake test video.

This is good to know, as this has been a major concern of mine too. Thanks!

[AndyM]

Yeah, hope I don't offend, but Real Oregonians drive in the snow like Real Californians drive in the rain! It's all good.

Californian transplants to here, are at least smart (terrified) enough when it snows, to stay home. Oregonians aren't. And I am one, but have learned, also have secret AWD weapon.

So as not to sling insults: any driving condition in which one has little practice means one will tend to suck at it. It's not personal.

[ckessel]

Yea, we Oregonians are pretty bad in snow. In our defense:

1) We get very little of it so people don't get much practice.
2) It's not the dry, blowing snow you get in mountains or Colorado or some such. It's nasty, wet stuff that often ices over, melts, ices, etc. It's really treacherous.

That doesn't excuse folks going out in it though, that's just not smart.

I simply don't drive in it. I'm horrible in the snow. My wife is pretty good at it though, she did a lot of skiing in her youth and drove snow covered roads.

[Lyon]

Yea, we Oregonians are pretty bad in snow. In our defense:

1) We get very little of it so people don't get much practice.
2) It's not the dry, blowing snow you get in mountains or Colorado or some such. It's nasty, wet stuff that often ices over, melts, ices, etc. It's really treacherous.

That doesn't excuse folks going out in it though, that's just not smart.

I simply don't drive in it. I'm horrible in the snow. My wife is pretty good at it though, she did a lot of skiing in her youth and drove snow covered roads.

Indeed. It's mostly the cities in the Valley that end up with people stranded all over the place with 2 inches of snow on the ground.

While a grew up in Eugene I've skied my whole life and have driven in the snow a lot.

The biggest mistakes I see when it snows in the Valley:

1) AWD is great to get you going and to keep to in line around corner but it doesn't help you stop.

2) The vast majority of"all-season" tires aren't. (If they don't have the Severe Service logo on them they're not really all-season)

3) slow down before you want to turn. You may have enough traction to corner and you may have enough to slow down but you don't have enough to do both at the same time.

I'm sure that this list could be expanded, but these are the big ones, IMHO.

[Doug_G]

10.8466% (1.0 - 3.37/3.78 * 100)

Is 11% significant? That is, if after tens of millions of miles almost no Roadster owner reports damaging rims or getting blowouts from potholes or bad roads, will an 11% decrease in sidewall height suddenly make it a real problem? Especially considering the air suspension?

I've bent a rim. Pothole.

[smorgasbord]

I've bent a rim. Pothole.

Is this the exception that proves the rule - or something to make us avoid 21" if our roads ain't so great?

How many miles do you think TMC posters have on their Roadsters, and how many damaged rims?

[SCW-Greg]

Is this the exception that proves the rule - or something to make us avoid 21" if our roads ain't so great?

How many miles do you think TMC posters have on their Roadsters, and how many damaged rims?

Quality of rim barrel might be at play as well here.

[Ken Edwards]

One more important factor to consider: range. Tesla engineers I spoke with all said the 19 inch wheels would get about 5% more range. If range (and economy) is important to you, and you want to save money and have more choice of tires and manufacturers, then the 19s are best for you. Overall this was enough of a factor to persuade me to go to the 19s even though I'm giving up an included $3,500 more expensive wheel (included in performance and signature cars).