High efficiency 20" wheels and ~34" tires options (R20 - 285/60 - 275/65 - 285/65 - 295/65)

[ksurfier]

Those look really good, if it’s like others have experienced then the MPK should improve after several hundred miles, but already sounds like it’s decent compared to 21s. I would guess those tires will last a long time too, maybe in 40k range give or take. Any rubbing on lowest settings?

Also, are you running them at 50 psi or 60-65 psi? (recommend at least 52 psi based on load rating of 3640#)

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[evmike]

Those look really good, if it’s like others have experienced then the MPK should improve after several hundred miles, but already sounds like it’s decent compared to 21s. I would guess those tires will last a long time too, maybe in 40k range give or take. Any rubbing on lowest settings?

Also, are you running them at 50 psi or 60-65 psi? (recommend at least 52 psi based on load rating of 3640#)

I haven't tested the lowest setting yet. I will have to check that out. I inflated them to 65. But I'm going to do a chalk test and make sure I'm wearing evenly

 

[ksurfier]

A

I only have about a hundred miles on them so far. I'm getting around 1.8 to 1.85 mpk so far. With my 21-in factory tires I was getting an average of 2.0 mpk over the last 12,000 miles. They look fantastic and have a very nice stance on the vehicle. I'm hoping as they get a few miles on them and break in a little bit my mpk will go up

Also, it's worth noting the average temps are low as this will drag down the MPK a lot.
Sounds like you may be getting close to the OEM 20" MPK of ~2.1 in 65 F weather.
Either way, it looks great and seems like a fair tradeoff if you can still get around 250 miles range...
A good check on how your efficiency is doing is the indicated range at 78% (100 kwh SOC)...
Note that at 70 mph and 53 F I was getting 1.9 MPK with the 20" OEM tires...

 

[ksurfier]

I haven't tested the lowest setting yet. I will have to check that out. I inflated them to 65. But I'm going to do a chalk test and make sure I'm wearing evenly

Any update on these? Hopefully they are breaking in nicely and you like the handling and MPK is going up…

 

[evmike]

Any update on these? Hopefully they are breaking in nicely and you like the handling and MPK is going up…

So far not great. Getting less than 1.5 mpk. It has been in the 30's and low 40's in the morning when I drive 8 miles to work so I'm sure that isn't helping. Still though, I averaged 2 mpk with my 21 inch tires so a 25% dip in range is rough. I'm hopeful that warmer weather helps a lot. The ride is decent and they are not too loud but I need to try lower pressure, 65 psi is a bit bumpy. They also slip a good bit under fast acceleration and heavy breaking.

Time will tell

 

[ksurfier]

So far not great. Getting less than 1.5 mpk. It has been in the 30's and low 40's in the morning when I drive 8 miles to work so I'm sure that isn't helping. Still though, I averaged 2 mpk with my 21 inch tires so a 25% dip in range is rough. I'm hopeful that warmer weather helps a lot. The ride is decent and they are not too loud but I need to try lower pressure, 65 psi is a bit bumpy. They also slip a good bit under fast acceleration and heavy breaking.

Time will tell

Are you preconditioning? That will make a difference in cold temps…

 

[evmike]

Another update. I'm not entirely sure what you mean by preconditioning. If you need warming up the cabin ahead of time, yes I am.

Yesterday I went to visit some family for Easter and had a good bit of driving there and home. I got substantially better mpk than I do with my everyday driving. 2.06mpk over 193miles.

I'm not sure how this will be affected when I lower the pressure. But I definitely need to lower the tire pressure because at 65 my dashboard and doors rattle over bumps.

 

[ksurfier]

Another update. I'm not entirely sure what you mean by preconditioning. If you need warming up the cabin ahead of time, yes I am.

Yesterday I went to visit some family for Easter and had a good bit of driving there and home. I got substantially better mpk than I do with my everyday driving. 2.06mpk over 193miles.

I'm not sure how this will be affected when I lower the pressure. But I definitely need to lower the tire pressure because at 65 my dashboard and doors rattle over bumps.

Scheduled departure which will preheat the battery so you don't waste energy on heating the battery during short drives...you could definitely take your tire pressure down to low 50s/high 40s...wouldn't recommend going below ~45 psi (= load of ~8,200#). 47 PSI will match the tire load needs if fully loaded...
Based on 2.06 MPK in 50F, sounds like you could be getting about the same as the OEM 20" tire (~2.3 MPK), so that's really great...what was your average speed (60 MPH)?

 

[ksurfier]

I only have about a hundred miles on them so far. I'm getting around 1.8 to 1.85 mpk so far. With my 21-in factory tires I was getting an average of 2.0 mpk over the last 12,000 miles. They look fantastic and have a very nice stance on the vehicle. I'm hoping as they get a few miles on them and break in a little bit my mpk will go up

Any update on your tires? They look really great! Did you find a lower pressure that works?

 

[MountainPassPerformance]

Hi Everyone, I just thought I would share our new wheels and quick range test in this thread.

https://www.mountainpassperformance.com/product/mpp-mega-terra-rivian-r1t-r1s-forged-wheels/

The wheels are currently available for preorder. We've been able to keep nearly the factory offset which has significant aerodynamic benefits - but it's also a really great off-road wheel!

Our drive from Montreal to Toronto over the weekend netted us the following results:

2.17 mi/kWh (2.23 after correcting for tire size change from OE 21s)

• 75mph cruise control for 100km. Same start/stop elevation
• 275/65/20 BFG KO3
• Quad motor in conserve mode
• HVAC off
• Tire pressure 60psi
• MPP Triple-L adjusters at +3F/-1R and height at lowest
• Mild tailwind (note this is likely helping the efficiency around 10% - will have to test on a calm day)
• Cloudy, 13 deg C (it seems the efficiency drops with hot asphalt)

The trip was done with a Cybertruck on a similar tire (285/65/20) and the efficiency of both vehicles was quite close actually, the Cybertruck is around 10% more efficient, but it has a smaller battery and doesn't charge as fast as the Rivian. So the Rivian is the clear long-distance winner!

Bolt-on aero covers are also coming in the future, and I'm sure with road-oriented EV tires the efficiency should increase substantially!

 

[mikehmb]

@MountainPassPerformance - the wheels show as $250/ea on the site but references in the notes that they are $975.

At 250 I’ll order today. Can you please confirm which price is accurate?

 

[MountainPassPerformance]

Haha, I wish we could do $250 a wheel!

The $250 is a pre-order deposit.

 

[Zorg]

Another update. I'm not entirely sure what you mean by preconditioning. If you need warming up the cabin ahead of time, yes I am.

Yesterday I went to visit some family for Easter and had a good bit of driving there and home. I got substantially better mpk than I do with my everyday driving. 2.06mpk over 193miles.

I'm not sure how this will be affected when I lower the pressure. But I definitely need to lower the tire pressure because at 65 my dashboard and doors rattle over bumps.

Any feedback on hwy driving in Conserve?

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