Rolling resistance stats for tires
 

Does anyone do measurements and reporting on tire rolling resistance?

I'm thinking of ditching the 20" wheels on the tesla but that leaves me needing to choose some replacement wheels and tires. I was really impressed with the Michelin 4S except for the range. And I've read that Tesla's version of the 4S has lower rolling resistance and from what you can buy elsewhere. So if I order 18" wheels with 4S off TireRack, my range will only get worse.

People with the Michelin Primacy MXM4 get significantly improved range. But the tire is shit. People seem to love the Conti DWS 06 all-seasons, but I've seen some folks say the range isn't great on them either, but it's all anecdotal comments.

Thoughts on how I can search for a decent-ish tire that is slightly better efficiency wise? I'd prefer either a really high performing all-season or a decent summer tire that has better rolling resistance. (Oh and I want them quiet and comfortable as well :D)

Tirerack compares rolling resistance as MPG when they do comparisons. Low rolling resistance and good performance aren’t easily compatible.

How close are you to using the edge of your range? It sounded like you enjoy driving the car, get some enjoyable tires. I haven't owned the primacy but test drove it, maybe 11 years ago, on an e39 530i... Meh for that car, so go from there. I did drive the dws (owned its predecessor as well as dw) those are better but they are not going to be fun/grippy/smooth as the michelin. Maybe the dw gets closer but not the a/s one.

This. And the eGolf proved that in my experience.

Oh yeah, look at that. The DW is even lower efficiency than the 4S. And a worse tire in almost every other dimension as well.

https://www.tirerack.com/tires/tests...y.jsp?ttid=223

Sure.. but it seems like everyone puts them into just two buckets. There has to be more of a spectrum.

In the winter, too close. But once it warms up and the heater is off maybe I'll forget all about my range complaints.

The 4S are pretty great. It'll be hard not to get them again unless it got me significant range savings.

Talk to me in 12 months. My problem with the high end Michelin’s is that they age out FAST. The Contis don’t seem to suffer from significant (for their use case) age related degradation.

Why are you so focused on range? Do you regularly find yourself just a few miles away from empty between charges?

Well, I don't get that low because it's not good for the battery. But I've had several times where I had to charge when I wished I didn't have to.

One cause is that I don't have a charger in my NYC parking space. I'll plan a weekend where I go to the city, then want to make a short trip somewhere, and think "crap, if I do that I'll need to charge on the way home tomorrow."

But extending the range can help even for medium distance round trips. The 4S cause 20% or more range reduction over the Primacy MXM4, which is what the 310 mile claimed range is based on. I also try to keep the battery between 80 and 20% charge. Put them together and I get about 150 miles per charge. So I can visit someone who lives 75 miles away without charging, as long as they don't ask to test drive my car while I'm there. And it's warm outside.

Once it gets warm out maybe it won't be an issue. What I'll probably do is get the 4S and start using the E46 again for longer trips.

So it wasn't a good plan to leave the E46 parked outside all winter on its PSS? :speechle:

Let me put it this way: On 2014 date coded PSS, in 60 degree weather, the E90 doesn’t get forward traction until 3rd gear. The DWS all seasons hook up fine (blinks lights in first, but no intrusive interference). Yes, the PSS have more cornering traction, but it’s hard to get over effectively losing the use of the engine in most conditions. Likewise, I have 2009 date coded Conti DWs that still feel good on the E30 M3.

And keep in mind that the e90 M3, coded to Euro mode has extremely permissive traction control.

I don’t understand your infatuation with babying the battery.

It’s ok to take it below 20% and over 80%. What you don’t want to do is let it sit at 100% for long periods. That’s why Tesla defaults to a 90% charge. Keeping it closer to an average state of charge of 50% is best for the battery — but that’s based on time.

I put 93k miles on a Model S 60 (which had 208 miles range) over 5 1/4 years. I also normally charged it to 90%, and only charged to 100% when I needed to for a road trip. I typically would plug in anywhere between 25% and 60% to charge, so probably had an average state of charge of 60-something percent (since that is really hard to measure...). I occasionally took it below 10%. When I sold the car, it had <10% degradation - my last 100% charge was 188 miles.

I never said I don't ever take it out of that range. But I don't plan to do it for my daily driving.

Where do you see that? Elon has commented that 80-->30 is better than 90-40 for daily commute
https://twitter.com/elonmusk/status/448466037441179649

That's a nontrivial amount. :dunno:

I very very much doubt that you will gain anywhere near 20% range between ps4s and primacy. If you look at tirerack mpg tests, the spread is 3mpg at the 20's. I'd say maybe 5%. Is that worth it? Just drive th wheels and tires you have. The 19's might be a little more comfortable, but I also doubt it's worth switching down. Most of the stiffness is coming from the suspension, no?

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Oh I'm not worrier about the stiffness. It's shockingly comfortable. I'm just worried the wheels are going to get destroyed.

But I might just gamble and see what happens.

Slow down a bit, avoid what you can. The rest is for wheel repair. Are 19s going to be magically stronger? Only a bit. Also keep the winter set on a bit longer while they patch it up in the spring.

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After this thread I decided I was going to sell the 20's and buy some 18's. Not worth driving around in such low profile tires.

But then I got lazy and never managed to find a buyer, and it's almost June.. so I decided to put the 20's back on until I fugue out what I'm doing.

Literally the next day after swapping them on I hit a pothole and dented 1, possibly 2 wheels.

Here's to excellent decision making and hindsight being 20-20

Are Tesla wheels really that shitty, or are the roads around you that bad?

The Tesla wheels really are that shitty

Suckage, but still a matter of probabilities.

Boxster is right at 20k. I've 3-4 bad hits, lost 2 tires (one to a bubble, the other I don't remember), but only one very minor bend (not visible, saw on the balancer on the inside barrel). Fortunately, it can be balanced out. 20's with 35 profile do suck in that sense.

Do 19's ensure no bends? Maybe fewer but not sure by how much. The 19's on my 5 (with 40 sidewall) were getting beat up as well by the best that Hudson, Bergen and NYC/LI can throw at them.

Porsche wheels are stronger than bmw, and the car is lighter so that helps.

I think it is both.

NYC and suburb roads sucked in 2007 when I left that area, I doubt they have gotten better since then. I know NJ has gotten worse

Long Island roads are terrible when it comes to potholes ... don’t ask me what happened maybe asphalt cost too much but damn the roads are horrible and the repairs are ridiculous.

Fortunately (and now I cursed myself) I never hit a pothole with the 911 ... my other cars haven’t had the same luck :toetap:

I was driving 65 mph on 84 towards PA. The road wasn't too bad overall. Until I heard a solid "boom, boom" as both driver side wheels hit. It looked like just another highway seam that was patched, but it turned out to be a gap with a hole.

The front wheel is clearly a little bent and there's a vibration in the steering wheel whlie driving. The rear might be OK but I have to take it off to inspect the inside rim. Both tires are still holding air.

Two questions

1. Can rims like this really be repaired? It's worth doing?

2. Has anyone tried to get reimbursed from the state for pothole damage? Apparently it's a thing.

Yes, rims can be repaired. I had a Tesla 21" rim done for $100, or 1/10 of what a new one cost. The trick is finding a place that can do it and getting the rim over there (and using something else on the car in the meantime).

Yes, but not always. Twice in 2003 I had bent wheels on my 330i from my (ex) wife striking potholes. The first one was repaired perfectly for much less than the cost of a new wheel. But the second wasn't repairable because the head seat had been deformed a little.

It's definitely worth stopping by a wheel repair shop, and letting them take a look.

Yeah I had rims repaired on my Audi A6. Had to build my own box to ship them to a place in PA.

Can't remember the name of the place, but they did a great job for reasonable price. (Terry referred me to them, he knows who they are)

Plaz has used the PA place as well. They are quite high end in their pricing these days but have a solid reputation (cheesy website notwithstanding):

http://www.wheelcollision.com/

I had good luck with a guy in Elizabeth, he was a master welder and made good wheels out of bad. However, on one wheel he did for me the clearcoat didn't hold up. He blamed my cleaners (perhaps rightly? I didn't know what I was doing) but that ended our relationship.

There is also place on rt46 in NJ though I haven't used them. I'm sure there are plenty in Matt's neck of the woods and he has a whole new truck to drive as backup as well as his wheels to shops.

I think Radial Tire uses Wheelcollision. They repaired a rim of mine that RT damaged.

That's them. I remember them being reasonable price wise, but this was back in 2001 or 2

I ordered a new set of 18's and Michelin 4S's off tirerack. I'll drive the Colorado until the arrive. THen I'll get dented rim repaired and sell the dumbass 20's.

Low-profile tires are dumb. I knew that and used them anyway, which makes me dumb.

My only question at this point is whether I sell them as a set, or sell them off one at a time to people who dented their 20's. :lol: JST, need any wheels yet? :D

Mine are dented but still balanced, but post when you sell.

I figure I should update here. I got the 18" tires with Michelin 4s.

TL;DR: Overall the tires are great. Love them. And I don't stress over hitting potholes now. But they are louder and require lower pressures.

Details:

There is no issue with sidewall squirm relative to the 20's. My 18" snows have a lot more turn in squish which makes them less fun. I assumed that was mostly tread squirm or softer sidewall material, and this confirms it. The 18" 4S still feel great.

However, they are louder. There is more road noise than Tesla's 20" variant, which had some kind of foam strip embedded in them. The model 3 lets in a decent amount of road noise and it's noticeable. The current noise level is a little disappointing, but I can live with it. It's still like a Mercedes compared to the Cayman R. :lol:

Inflated to the same tire pressure (40psi) the 18" tires are actually more harsh than the 20" variant. I was always amazed at how complaint they were. However they needed even higher pressure to avoid denting the rims. The 18's allow me to safely lower them a few PSI at which point they become as comfortable as the 20's.

WTF you ask, how can an 18" be more harsh? I'm not entirely sure I understand, but I believe it's the little understood phenomenon of tire casing pressure and barlow's law. Think about bicycle tires. The larger the tire, the lower pressure you run to achieve the same ride quality and sag pct. A 1" road bike tire may be pumped to 100psi, a 2.5" mountain bike to 25psi, and a 5" fatbike tire to 8 PSI. The 18" wheel's tire has a larger rubber surface area.

This article gets into the math http://flocycling.blogspot.com/2014/...less-tire.html

I ran into this when considering going from 23mm to 25mm width tires on my road bike.

At the same tread width and total diameter, they should have very similar contact patch area; but the higher sidewall simply has more air; so it could support more weight. If you are looking for a certain drop on the sidewall (bicycle style), you might need less air in the larger profile. I'll read about the casing tension, that probably has some to do with drop; but think about the supported weight as well.

Are you surprised that the tire that Michelin is giving super stiff sidewalls is stiff?

No. The original 20's were the same tire

Seems I'm not the only one.

https://youtu.be/H6sPc9dFsGw