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Roof lights?

iansriv

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Love the look of the Urban roof lights on the black defender. Wonder if something similar can be had for the Rivian? Also, thinking of fender flares for a full on "urban" assault vehicle look.


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Polar

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I’m sure all the accessories you can imagine/want will come in time.

Those don’t compare to five lightbar mounted 8-10” KC Highlights - but I must be aging myself here.
 

NY_Rob

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I’m sure all the accessories you can imagine/want will come in time.

Those don’t compare to five lightbar mounted 8-10” KC Highlights - but I must be aging myself here.
Lol... I had the KC's on my CJ7 back in the early 80's. IRC I had six of them on the chrome lightbar. I just loved when idiots were coming at me with their highbeams on and refused to swithch to lowbeams :cool:
 

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mkg3

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Maybe someone will be cleaver enough to invent a thin LED strip light that folds flat onto the roof of the vehicle with an airfoil like profile to minimize drag impact on the vehicle. So it can deploy upright when needed/in-use, then fold back down flat when not. (beacon roof lights will separate the airflow at the end of the windshield, whereas without them, they won't separate until the end of the cab - it may seem trivial but it really impacts the range of EVs, since drag behaves with velocity squared)

These roof top beacons probably decrease the range by 5% or more, so add that onto the 20" AT tires' 10~15% reduction. With roof beacons, now the range is reduced by 15~20% from EPA 314 miles, or down to 251 miles. Not horrible but in real driving conditions, its probably closer to 230 miles or less.

... where is the Max Pack now???
 

ironpig

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Maybe someone will be cleaver enough to invent a thin LED strip light that folds flat onto the roof of the vehicle with an airfoil like profile to minimize drag impact on the vehicle. So it can deploy upright when needed/in-use, then fold back down flat when not. (beacon roof lights will separate the airflow at the end of the windshield, whereas without them, they won't separate until the end of the cab - it may seem trivial but it really impacts the range of EVs, since drag behaves with velocity squared)

These roof top beacons probably decrease the range by 5% or more, so add that onto the 20" AT tires' 10~15% reduction. With roof beacons, now the range is reduced by 15~20% from EPA 314 miles, or down to 251 miles. Not horrible but in real driving conditions, its probably closer to 230 miles or less.

... where is the Max Pack now???
This is the same issue for ICE vehicles. I have a FrontRunner rack with an LED light bar across the front of it on my 4Runner. It certainly decreases range by adding drag. But the reality is I only use it a few times a year when I am driving up a dirt road near my cabin and want max illumination at night. I could get by without it and assuming the high beams on the Rivian are pretty good, I won't be adding extra lights to it.

I have a neighbor who has a Model Y on AT tires with a basket and light bar on top. I think if you really need it, the minor range hit is just something you have to accept.
 

OldGoat

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Range reductions are not additive from the top end. For example, (to make the math easier, start with 300 mile range) do something to reduce range by 15% (e.g., AT tires), range is now 265 miles (300 - 45). If I do something else that reduces it by 15%, my range is now 225 (265-39.5) cold weather, another 20% and I'm at 180 miles (225 - 45). You can't just add up 15 + 15 + 20 come up with 50% and say your range is half of the original 150.

Think about it this way...I run in frigid weather, lose 25%, tow a trailer, lose 40%, run AT tires lose 15%, drive uphill, lose another 20%, drive in sport mode, lose 10% and poof my range would now mean I must drive in reverse for 30 miles! :)

(This seems to be one of those counter-intuitive math principles for many as it seems like the order in which the reductions are made would impact the final answer and, therefore, it must be additive...I mean certainly if I take x * .80 = y y * .85 = z z * .90 = final range I will get a different result than if I take x * .9 = y y * .85 = z z* .80 = final range !!)
 

mkg3

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Range reductions are not additive from the top end. For example, (to make the math easier, start with 300 mile range) do something to reduce range by 15% (e.g., AT tires), range is now 265 miles (300 - 45). If I do something else that reduces it by 15%, my range is now 225 (265-39.5) cold weather, another 20% and I'm at 180 miles (225 - 45). You can't just add up 15 + 15 + 20 come up with 50% and say your range is half of the original 150.

Think about it this way...I run in frigid weather, lose 25%, tow a trailer, lose 40%, run AT tires lose 15%, drive uphill, lose another 20%, drive in sport mode, lose 10% and poof my range would now mean I must drive in reverse for 30 miles! :)

(This seems to be one of those counter-intuitive math principles for many as it seems like the order in which the reductions are made would impact the final answer and, therefore, it must be additive...I mean certainly if I take x * .80 = y y * .85 = z z * .90 = final range I will get a different result than if I take x * .9 = y y * .85 = z z* .80 = final range !!)
You do have a point but my original comment about 5% reduction was from the original EPA mileage. It would happen on the 21" AW tires. So if you look at the range loss due to drag increase by itself of 5%, and 20" AT tire loss of 10~15%. In this case, range loss due to drag force increase would be greater than 5%.

It is true that the combined effects are not necessary sum of the parts, if they are dependent to one another. In this case, they are totally independent losses (tires cause inertial and rolling resistance, and acoustic changes, and lights causes form drag and induced drag changes).
 

Sierra7117

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I'm thinking something like the unibar from lightforce would help minimize drag by keeping driving lights on the leading edge of the truck. Thoughts? Idea of drilling holes in the bumper for a plate bracket is saddening though...
Rivian R1T R1S Roof lights? unibar_h
 

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NY_Rob

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For offroading, you generally want the lights mounted as high up as possible vs. driving lights mounted at the same height as the headlights.
 

OldGoat

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It is true that the combined effects are not necessary sum of the parts, if they are dependent to one another. In this case, they are totally independent losses (tires cause inertial and rolling resistance, and acoustic changes, and lights causes form drag and induced drag changes).
Definitely is counterintuitive; however, it is the case even if they are independent factors. For example, if you have three completely independent factors that impact range of 20% each, the total impact is not 60%, it is less than 50%.
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