Growing efficiency Gap: R2 w/ 21" vs. 20" tire sets

[Mos Eisley]

I suspect two things.

1. The 21" wheel design is just not aero efficient
2. The 20" ATs are more for highway and not real ATs

The range difference between them is really small at 70 MPH. Yeah you'll take a hit but not as much as you'd think compared to R1. I doubt as many people are going to "touch dirt" with their R2 compared to R1.

Range estimates will be more accurate on the ATs over AS. Seems like Rivian really pushed the range estimates with the AS to "beat" the Model Y on paper.

That is to say you'll see closer to stated range with the ATs over AS.

I agree with all of that - with the biggest takeaway: it doesn't matter significantly one over the other for most typical use cases. Which leaves the bigger decision still whether the Pirelli's for R2 will exhibit more life than those for R1 rolling the dice on what, if any, new 21" options will be available in 24 months.

Sponsored

 

[ATXR2]

I went with the 20s and here's why:
1- I like they way they look.
2a- There are options for replacement when the time comes. If I gain some efficiency back with all seasons, great, if not, that's ok too.
2b- They are close enough in stated efficiency that the difference doesn't matter to me.

I think that the data being gathered by roamer is interesting and fun to look at, but there are way too many variables for it to be really useful for predicting anything for me.

 

[caffeinated]

I suspect two things.

1. The 21" wheel design is just not aero efficient
2. The 20" ATs are more for highway and not real ATs

The range difference between them is really small at 70 MPH. Yeah you'll take a hit but not as much as you'd think compared to R1. I doubt as many people are going to "touch dirt" with their R2 compared to R1.

Range estimates will be more accurate on the ATs over AS. Seems like Rivian really pushed the range estimates with the AS to "beat" the Model Y on paper.

That is to say you'll see closer to stated range with the ATs over AS.

On point 1, I have been very interested in seeing what range the premium trim's 20" aero-ish wheels get.

 

[Rivian Roamer]

On point 1, I have been very interested in seeing what range the premium trim's 20" aero-ish wheels get.

Same.

 

[tivoboy]

I see an aftermarket for some sort of well designed 3-D molded aero wheel insert for the 21 inch wheels

 

[ksurfier]

Same.

If you dig into the actual rims, it looks like there is no obvious reason for assuming the 21” rim is aerodynamically superior. The 20” actually appears to have less outer-radius opening and could produce lower wheel-induced aerodynamic drag. It will be interesting to see a light weight 20” AS paired with the OEM rims.

 

[tivoboy]

If you dig into the actual rims, it looks like there is no obvious reason for assuming the 21” rim is aerodynamically superior. The 20” actually appears to have less outer-radius opening and could produce lower wheel-induced aerodynamic drag. It will be interesting to see a light weight 20” AS paired with the OEM rims.

I do prefer the 20 inch rim, I just don’t like the thought of having to drop at least $2500 to get them and have them fitted with a good set of. AS tires. And then have a set of ATS that I have no use for.

 

[Rivian Roamer]

If you dig into the actual rims, it looks like there is no obvious reason for assuming the 21” rim is aerodynamically superior. The 20” actually appears to have less outer-radius opening and could produce lower wheel-induced aerodynamic drag. It will be interesting to see a light weight 20” AS paired with the OEM rims.

If you're referencing my comment about aero, I think you have it backwards. I said the 21" is less aerodynamic. Lots of sharp edges, less surface area.

 

[ksurfier]

If you're referencing my comment about aero, I think you have it backwards. I said the 21" is less aerodynamic. Lots of sharp edges, less surface area.

Maybe got confused by your earlier comment, but sounds like if the 21” aero issues could be addressed (inserts), then we might see the efficiency tick up from 2.6 MPK to maybe 2.7 MPK?

 

[caffeinated]

Everybody laughed at happy squares. Well who's laughing now??

 

[richpike]

I love those wheels.

-Rich

 

[NCSwa]

I honestly feel like once the 19" wheel is released that may be the go to. I think it looks very similar to the 20" AT wheel, and if we get even more cushion and choices, I think that will be a winner.

 

[NCSwa]

I mean this with the Yellow Calipers from the Launch will look very Nice IMO

 

[richpike]

I honestly feel like once the 19" wheel is released that may be the go to. I think it looks very similar to the 20" AT wheel, and if we get even more cushion and choices, I think that will be a winner.

Having had 19” on many of our land rovers over the years it’s a pretty unusual wheel size so doesn’t seem to get much love. Especially in the 32” tire size we have on our Defender now (and what the 19” for the R2 will be). DomDoesMedia (Dominic) is trying a set of 18” wheels for his R2 - will be super interesting to see what he learns.

-Rich

 

[ksurfier]

Having had 19” on many of our land rovers over the years it’s a pretty unusual wheel size so doesn’t seem to get much love. Especially in the 32” tire size we have on our Defender now (and what the 19” for the R2 will be). DomDoesMedia (Dominic) is trying a set of 18” wheels for his R2 - will be super interesting to see what he learns.

-Rich

Yeah, unfortunately 19/21” fall into the same odd category where there are few options. I would definitely take the 19 over the 21” any day. 18” would be ideal offroad size, something missing from the R1 options (caliper is too big).

Sponsored