[AmerikanMatt]

Anybody seen this article?

Rivian R1T on Street Tires Went 60 Miles Farther in Highway Test (caranddriver.com)

I have two questions for the group:

#1 - Do you believe the difference is really this drastic? Do you believe it's all from the tire/wheel size?

#2 - I currently have the 20" AT spec'd as I plan to do some overlanding, camping, etc.... but not a TON of it... you know, maybe 1 weekend/month? The rest is standard urban/freeway driving.

If you were me, do you believe the off-road performance with the 22" Road wheels would be diminished enough to make it worth the lost range to stick with the 20's? Contrarily, any insight into the road-feel of the 20's vs. 22's?

I guess I'm trying to figure out - if we know the 22's get way better range, how different is the performance between the two wheel sets both on and off-road? Will I notice a huge difference in either with a particular configuration?

Based on my usage, would I be unhappy with road wheels as an outdoor enthusiast?

 

[O. horridus]

#1

C&D's previous test with the 20" tires measured an exceptionally short range that is inconsistent with what everyone here and on other forums is reporting. This new test with 22" is a only little low. Their huge reported discrepancy between the two is mainly due to their previous test being so out of whack.

Your range with the 22" should be 5-10% less than with the 21".
Your range with the 20" should be 10-15% less than with the 21".

The question is, less than what? For that the EPA range is a standard measure under known conditions. But because those known conditions don't necessarily reflect how you use your vehicle, that EPA range is useful mainly as a baseline, and needs to be adjusted on an individual basis for your driving style, for your normal speeds, for your typical terrain and weather conditions, etc.. Fortunately this personal adjustment is similar across all vehicles. So if you usually get better than EPA numbers on your current vehicles, you will probably get better than EPA numbers on your Rivian. Likewise, if you usually get worse mileage than advertised on your other cars, chances are you will get worse mileage on your Rivian.

The "real world tests" that everyone is so fond of are actually the worst way to gauge vehicle mileage/range. Because by definition "real world" means a non-standardized test environment that is only representative of itself - if how you use your vehicles differs (and it will differ - there are literally an infinite number of situations in which to test, and the chances that your personal usage matches that is, as a result, quite small) then there is no way to extrapolate what your mileage/range will be. And that's what people are looking for in these "real world" tests - they are only trying to figure out what their own result will be.

#2

If range is of primary importance to you, you will get the best range with the 21". The 21" are also adequate for your planned off-road usage. The 22" are relatively worse off-road. The 20" are relatively better off-road. I personally am getting 20" because I like the looks much better, I will be using them more off-road than you, and I would prefer to have the larger sidewalls for more safety margin. The difference in handling between the 20" and 21"/22" is totally irrelevant for the type of driving I do. I expect to get around 300 miles of range on the 20", like many others have reported, because I always get above the EPA rating the way I use my vehicles. That's more than I get with my current ICE adventure vehicle, so no range anxiety here.

Regardless, I think your choice of tires is a personal question that only you can answer. Which aspect is going to affect you most, range or performance? Both the 20" and the 22" are more specialized than the stock 21". If range is most important, get the 21" without a doubt. If off-road performance is more of a concern than range, get the 20". If on-road performance is more of a concern than range, get the 22".

 

[thebishman]

If you read the article you’ll see that the ambient temperature when they reviewed the range of the 20”s was only in the fifty degree range, whereas the 22”s were tested close to the most efficient ambient temperature which is 80dF. That temperature Delta has a much greater influence on range than the diameter of the tyres, although obviously the 20”s are the least efficient.

 

[ColeAK]

#2 what is your definition of overlanding and off roading? If it is just gravel roads you will be fine with 22’s. Any more then that get the 20’s. Any amount of sand, mud, exposed small rocks (as in ~golfball size ) the 22’s will be useless and dangerous.

For safely (and not having to deal with flats and rim damage) On the number system I’d say for the 22’s grade 2 max and for the 20’s grade 4 possibly 5 is there are no large rocks/shelf’s.

FAQ: Is There a Universal Difficulty Rating System for OHV Trails? - American Trails

www.americantrails.org

 

[Yellow Buddy]

#2 what is your definition of overlanding and off roading? If it is just gravel roads you will be fine with 22’s. Any more then that get the 20’s. Any amount of sand, mud, exposed small rocks (as in ~golfball size ) the 22’s will be useless and dangerous.

For safely (and not having to deal with flats and rim damage) On the number system I’d say for the 22’s grade 2 max and for the 20’s grade 4 possibly 5 is there are no large rocks/shelf’s.

FAQ: Is There a Universal Difficulty Rating System for OHV Trails? - American Trails

www.americantrails.org

Pirelli has its own grading system. The 20s are a 9/10 for off reading and the 22s are a 4/10. The 21s are 3/10. But the road definition matters a lot more here than those ratings IMO.

 

[ColeAK]

Pirelli has its own grading system. The 20s are a 9/10 for off reading and the 22s are a 4/10. The 21s are 3/10. But the road definition matters a lot more here than those ratings IMO.

That is for a comparison of pirelli tires one to the next. Completely nothing to do with how capable a tire is on a trail as composited to other brands or anything to do with the trail difficulty rating. It also doesn’t take into consideration tire /rim size.

larger rims (and less tire sidewall) are one of the largest hinderance of off road ability. A truck that will be taken off road has no business with rims >18”.The Pirelli all seasons (that come on the 21”) rims in 275/85-17 on a 17” rim will be exponentially more capable then the AT tire (that comes on the 20”) in a 275/55-22 on the OEM
22” rim.

all that said you probably could run the Scorpion AT tire on a level 9 trail on a wrangler/bronco/modded 80 series on 35”x12.5 on 17” bead locks. But the same tire not reliably more then a level 4 with the 275/65-20”.

 

[BadKarma!]

I too have spec'd the 20" AT's for my R1S as I live in New England. We have crappy, pot holed, roads in CT but my main reason for the 20's is for snow traction in the winter. I'm coming out of a 4-door Wrangler that had OEM off road tires and it was fine. Only two sets in 13 years!

Am I looking at it incorrectly?

 

[racekarl]

As an educated guess, Connecticut gets around 30 days of snow per year. Assuming you drove a representative proportion of days in all weather conditions, you're talking about less than 10% of your driving days.

The AT tires likely have worse handling and braking performance in dry (and perhaps wet) conditions, which represent 90% of your driving. On top of that you will pay a ~10% energy penalty and endure worse NVH 100% of the time.

Unless you actually go off road and need them, or are enamored of their looks relative to the road tires (both understandable) then road tires are the right choice over AT tires.

 

[BadKarma!]

As an educated guess, Connecticut gets around 30 days of snow per year. Assuming you drove a representative proportion of days in all weather conditions, you're talking about less than 10% of your driving days.

The AT tires likely have worse handling and braking performance in dry (and perhaps wet) conditions, which represent 90% of your driving. On top of that you will pay a ~10% energy penalty and endure worse NVH 100% of the time.

Unless you actually go off road and need them, or are enamored of their looks relative to the road tires (both understandable) then road tires are the right choice over AT tires.

Interesting insight. Thank you.

Gives me something to think about.

 

[cmerritt408]

Nobody's mentioned that the 20" tires are larger diameter yet, googled and found from America's Tire Co:
"The Rivian R1T has a range of stock tire sizes, including 275/65R20 tires, 275/55R21 tires and 275/50R22 tires. While the 21’’ and 22’’ rim diameters are 33-inch tires, the tire with the 20’’ rim diameters is a 34-inch tire, making it the likely choice for your off-road pursuits."

That means a few things...the 20" shod vehicle is going to be .5" taller, increasing wind resistance.
Is the odometer really going to report exactly the same? C&D wasn't clear on their testing procedures, if they were just trusting the Odo' instead of using a test track or google maps or GPS to measure the route, then that could also bias things by several percent (traveling further than reported due to the larger circumference).
And then the weather...that was dumb, 57F would be way worse than the 85F day for an EV.

Need to eat a little crow, clicked on the 'how we test' C&D link and found they do put real effort into correcting the Odo', so kudos to them:
"We run all our tests at a GPS-verified 75 mph on the same 200-mile out-and-back loop on Michigan's I-94 highway. Our consistent procedure includes a methodical fill-up process, following a specific route, using cruise control, and setting the climate control to the same temperature (72 degrees auto). We also correct for odometer error, and we don't test in heavy wind or rain or with extra passengers. In the event we encounter too much traffic or unusual conditions, we abort the run and try again later. "

 

[dgillies250]

I too have been wrestling with rim size / tire use. In a perfect world I would get 20” rims (looks and bump/pot hole cushioning) with a road tire(preferably the same spec as the tire that comes on the 21” rim). My current thinking is 20” rims, replace the worn factory tire with an appropriate road tire. Maybe Pirelli will create one.
Thoughts?

 

[cmerritt408]

...My current thinking is 20” rims, replace the worn factory tire with an appropriate road tire. Maybe Pirelli will create one.
Thoughts?

Tire Rack has 10 all-season tires in 275/65-20
If you mean 33", I.E. 275/60-20, let's see...yeah like 30 options, and much cheaper too.

 

[ColeAK]

I too have been wrestling with rim size / tire use. In a perfect world I would get 20” rims (looks and bump/pot hole cushioning) with a road tire(preferably the same spec as the tire that comes on the 21” rim). My current thinking is 20” rims, replace the worn factory tire with an appropriate road tire. Maybe Pirelli will create one.
Thoughts?

For best performance and ride across the board put the smallest rim that will clear the brakes. So in question go with the 20

 

[AmerikanMatt]

Wow….. bunch of great insight…….. (to be expected of course from this group). Thanks everyone.
Interestingly, for my questions, it seems that if the answer to my Question #1 was that “no, the test results are misleading”, then my question #2 would have less relevance.

Great advice and insight all around however. Tough choice….. tire/wheel size on a sweet, $90k truck……. Right?

then comes this:

For best performance and ride across the board put the smallest rim that will clear the brakes. So in question go with the 20

Please….. enlighten us?

 

[RITVT]

It's true that 20's will allow for potentially more sidewall to fill the wheel well, giving a softer feeling & nicer ride in a heavy Truck or SUV, but "performance" can be subjective. More sidewall and less wheel can feel more squirrely at speed going around corners on pavement for example, and softer rubber compounds with more tread can also feel squishy and softer in the summer heat. They will def give you the best performance for all of the above reasons in any off-road situation given the traction differential. However, if you have the desire to drive your truck or SUV more like a car on HWY surfaces, a bigger wheel with a dedicated summer tire (less sidewall, firmer compound, less tread) will perform much better on-road than an AT for that purpose. Just watch out for potholes. The answer here is really to have 2 sets of wheels and tires. It's an upfront investment, but won't cost you much over time since you typically use them 1/2 the year. This assumes you live in a place with Summer and Winter, and that you are a tire nerd.

 

[dgillies250]

It's true that 20's will allow for potentially more sidewall to fill the wheel well, giving a softer feeling & nicer ride in a heavy Truck or SUV, but "performance" can be subjective. More sidewall and less wheel can feel more squirrely at speed going around corners on pavement for example, and softer rubber compounds with more tread can also feel squishy and softer in the summer heat. They will def give you the best performance for all of the above reasons in any off-road situation given the traction differential. However, if you have the desire to drive your truck or SUV more like a car on HWY surfaces, a bigger wheel with a dedicated summer tire (less sidewall, firmer compound, less tread) will perform much better on-road than an AT for that purpose. Just watch out for potholes. The answer here is really to have 2 sets of wheels and tires. It's an upfront investment, but won't cost you much over time since you typically use them 1/2 the year. This assumes you live in a place with Summer and Winter, and that you are a tire nerd.

I am a tire nerd and live in New England. For me it’s about performance in the snow and decent behavior the rest of the year. I spend a lot of time in VT and 30 years ago in a different car you might have found me pushing the limits of tire adhesion but we now share the road with far more cars, bike riders, kids, et al. This is my first pickup truck and it’s about stopping and starting these days. Any thoughts on pickups and snow tires? I’m a Evangelist when it comes to snow tires.

 

[racekarl]

A true evangelist would call for "winter tires" instead of "snow tires" They offer so much more than just snow traction; the different rubber compounds can offer better grip at low winter temperatures even when the roads are clear and dry. Many all-season tires qualify to wear the "snow tire" symbol these days.

I learned to drive in NH so I am also a winter tire nerd - I always had two sets of wheels and swapped twice a year from dedicated winters to dedicated summers and back.

Traditionally, pick up trucks have been abysmal in the snow, and no tire could undo that so it barely mattered (we never swapped on our truck). The Rivian is going to be so much better than a traditional pick up in terms of snow performance that it might be worth considering if you do a lot of winter driving in cold climates.

That being said, tires have gotten so much better that I just roll all-seasons (with the snowflake symbol) year round and don't worry too much about it. I currently have the 21" road wheels (with all-seasons) spec'd and just plan to use those year round on the Rivian.

 

[ColeAK]

Wow….. bunch of great insight…….. (to be expected of course from this group). Thanks everyone.
Interestingly, for my questions, it seems that if the answer to my Question #1 was that “no, the test results are misleading”, then my question #2 would have less relevance.

Great advice and insight all around however. Tough choice….. tire/wheel size on a sweet, $90k truck……. Right?

then comes this:



Please….. enlighten us?

I raced SCCA then eventually GT3. When it comes to wheels on track cars the saying is only reason to run larger wheels is to fit larger brakes. On road (and track). Larger rims give more rotational mass more rotational mass slows acceleration and increases braking distances and decreases efficiency. Sidewall is more aerodynamic then rim so when comparing the same rim/tire larger rims are less efficient. Larger rims give less sidewall, less sidewall give less tire flex less tire flex equals more body roll leading to less grip in corners, less grip acceleration, and less grip braking. When F1 spec switched from 15” to 18” rims to give the cars a more “modern” look lap times got slower across the board. The only place larger rims are a performance advantage is the fast and furious franchise and video games.

unfortunately US consumers have been brainwashed to believe large rims are better….

off road. Rule #1 off road is air down. On my summer tires daily driving I run 36 psi. I air down to 30 for long dirt/gravel roads, 28 psi for general off road trails and 20-25 psi for sand depending on how soft. Larger rims give less room between rim and ground and a much higher chance to roll the tire off the bead and pinch flats. It’s hunting season and I’ve already helped out 2 guys with 20” rims and pinch flats. For even mild trails The general guidance is maximum rim size should be ~half tire OD. A 33” tire on 17” rim is considered the minimum requirement off road.

my buddies dad had had 3 pinch flats on his f150 with E rated 285/60-20. Finally switched to 285/75-17 this summer.

 

[ColeAK]

A true evangelist would call for "winter tires" instead of "snow tires" They offer so much more than just snow traction; the different rubber compounds can offer better grip at low winter temperatures even when the roads are clear and dry. Many all-season tires qualify to wear the "snow tire" symbol these days.

I learned to drive in NH so I am also a winter tire nerd - I always had two sets of wheels and swapped twice a year from dedicated winters to dedicated summers and back.

Traditionally, pick up trucks have been abysmal in the snow, and no tire could undo that so it barely mattered (we never swapped on our truck). The Rivian is going to be so much better than a traditional pick up in terms of snow performance that it might be worth considering if you do a lot of winter driving in cold climates.

That being said, tires have gotten so much better that I just roll all-seasons (with the snowflake symbol) year round and don't worry too much about it. I currently have the 21" road wheels (with all-seasons) spec'd and just plan to use those year round on the Rivian.

In alaska and also a winter tire enthusiast. I’d argue that 7k lbs of truck will need winter tires more then most. Weight+ice=sled. I’ve run Nokian Hakka’s exclusively for at least 15 years. Looks like Nokian is making the Hakka 10 in a 21”. Here is My Tesla on Hakka 9’s.

 

[dgillies250]

Supposedly I take delivery November/December. I’ll run the stock tire that comes with the 20” this winter. Apparently it’s a “snowflake” tire. What I’m really looking forward to is to see how regen braking works on snow/ice. I wonder if there is an “anti-lock” setting. Probably have to wait for a software update.