Thule Arcos cargo box efficiency test
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- čas přidán 6. 08. 2024
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I am very glad to see the active lights on the Arcos - this prevents the backup sensors from "panicking" and jamming on the brakes when you reverse the car.
Amazing effort! Thanks for all the hard work Björn! Appreciated.
Very appreciated indeed! Thank you Björn, i watch nearly every Video from you, because of the unmatched results and uncommon but very helpful Tests! 🥰👏
I’d go with the rear box because of the consumption difference, and the ease of install is a nice bonus. Plus if I was going camping there would be room on the roof for a canoe or bicycles.
I wonder if there will be Trailerhitchboxes in the future that look more like an added boattail for specific cars. So if you build a box specifically for one car, this could significantly increase the efficiency on the highway by lowering the Cd.
Thank you Bjørn for making tests , and thinking out of the “box” 😅
I have the Arcos and borrowed a friend’s roof box on two separate trips this summer on our Model 3. My data showed that the roof box (Thule Motion XT Alpine) trips averaged 213Wh/km and the Arcos only 162Wh/km. These were on different days and took different routes, but were balanced (there and back trips). Unfortunately I can’t directly compare to prior long distance trips without either box because I switched to heavier rims and different tires this year, but those trips were closer to 174Wh/km and 145Wh/km respectively for the stock Model 3 setup.
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How was supercharging with the arcos rear cargo box? Do you just back in all the way like normal and hose reaches with no problem? Did you try on multiple supercharging stations?
@@theticoboy We found that the V2 superchargers had longer cables, so navigated to those. But it was a 2 person job of backing up as close as possible. For V3 chargers, we had to pull in to the last stall at the end, sideways, so we didn’t block any other spots. With superchargers opening up to Ford and Rivian, they are removing the bollards, so this year we may be able to use V3s the normal way. Also, if there is a pull in stall, those would work perfectly.
@@stevemint thanks just this picked up a used new in box one today for great price. Easy to install. You were dead on re supercharging. It is a 2 person job. I had to get within an inch of the Ballard to get the cord to reach. It was a 250 kW station. Thanks again for your feedback. I’m liking the box so far!
Can you drive with autopilot with the Arcos?
Love this video Bjørn. I have been planning to get a rear box for my model S and really wanted this comparison test to be done by someone in Norway.
And yes the efficiency with the rear box is better than without it. This has been tested and documented by Thule and is available on their website, they have proven it by testing it in windtunnel indoors as well as in real world. The efficiency improvement with the rear box is higher for SUVs than for sedans
Perfectly logical, since it fills the "vacuum bubble" that the rear of the car generates a bit. The larger the bubble, the more benefit in drag force reduction.
Regarding the whistling noise of the roof solution I would like to point out that the mounting bars used in the test most likely have a short (10cm) plastic cover on each side underneath the bars. It is supposed to close the opening that is needed for width adjustment of the bar feed. On our Thule model it makes a big difference in noise especially at speeds above 100km/h.
I have cargo box on kona and i can say the consumption is lower or maybe the same but for sure not higher. But this one in test is smaller, mine is 340l. Happy that you did the test finally, on hatchbacks it surely makes sence, also no back wiper needed when box is on.
I was talking to a guy from Thule at an exhibition a couple of weeks ago. He said that they couldn't claim it was more rigid but there's a trip that colleagues make and they barely make it without a box. Can't make the trip with a roofbox, but easily make it with the box on the rear.
Good test Björn!
In Germany is a Trailerhitch available for ID3 and Cupra Born with 1500kg tow load.
Is towing allowed from VW on the ID.3?
Really good evaluation! Thank you.
Change on!
I am using rear box for a 4 years on my TM3. I have a combination of bike the carrier THULE VeloSpace XT 2 938 with 300l box THULE BackSpace XT and it is perfect.
(Aids from Thailand)
The position of the roof box can make more noise.
From the installation manual, we should install roof box in the end of the roof as much as we can open trunk.
It will help for good aerodynamic, less drag and less noise.
Please, test for us again to compare the difference.
Thank you in advance.
Thx for making this video!
I am not surprised. I noticed similar behaviour (lower drag) with a Thule BackSpace XT on a KIA e-soul. I once even used
RoofBox (Calix Aero) + BackSpace for a Holiyday Trip. Had no issues with consumptuon /range. However, the Calix Roofbox does add some neglegable drag.
Rear box definitely! NICE!
Björn, can you please consider making A & B test comparing:
Roof box + two-three bicycles on the tow hitch.
&
Two-three bicycles on the roof and the box on the tow hitch.
Thinking two adult bikes and a small child bike.
I'm sure you weren't surprised that the rear box has the potential to make the car more aerodynamic. And it looks like there is space to add 100 litres to the rear and probably make the aero even better and still open the tailgate, there was a lot of clearance when you opened the tailgate. If you could add sensors or a camera to help with reversing, then there would be zero downsides. Great content as always. I hope you are soon in your new home.
Very interesting test, thank you! The only problem with the rear box might be, that the charging cables on some HPC might be to short if you want to park correctly.
Amazing results
I'd like to see a variation on this test with bike racks (and bikes) instead of cargo boxes.
Rear racks would almost certainly be more efficient and easier to load, but it'd be interesting to see the impact to consumption
A bike rack with 1 or 2 bikes on my model 3 LR does have a impact on consumption. But I drive 127km/h on the motorway. I think the consumption is around 30% more.
Agreed@@FIGHTTHECABLE the bike does make a difference I think more like 10-15% @ 100km/h but on the roof efficiency is terrible. It was way worse on my ICE car before I got an EV so I switched to hitch mounted racks as I do a lot of km's with bikes on the back.
I like bike roof racks as you can leave them on all summer and put bikes on/off in 5 minutes. Rear towbar mounts are (a) more hassle (b) can block the rear mirror view and (c) block cameras needed for driver assist. When I've got mine on the car stops with the automatic lane change. But it's the only way to get electric MTBs around unless you buy a Buzz or similar. Maybe in future Thule will work with the car manufacturers so rear mirror cameras can actually connect to cameras built into the rack -they could just do HomeAV networking over the existing cables
@@SteveLoughran I wouldn't be too thrilled at lifting a 20kg E-bike up to the roof, particularly with a glass roof. Wouldn't be the best holiday experience dropping a bike into your car 😱
For that reason I'd prefer the rear loading, but I do agree it's annoying that it blocks the rear camera. They should be able to integrate a camera into the bike rack, but they do get banged around a lot so there's potential for it to get damaged easily
A bike with the wheels in place is longer than the aria behind the car thats 'free of airflow' so the edges of the wheels disturb the airflow and increase the aerodynamic coëfficient. If u take out the front wheel, the bike would be short enough to be in the 'free of airfow' zone (±0,8 x the width of the car at the back).
I've used the Thule BackSpace XT hitch box for a Croatia Holiday on the Ioniq 5 and even fully loaded I got under 20kwh per 100km with moderate speed. I'm looking to buy one permanently. The volume is the same as a ln ID3 trunk
this was cool! I never knew this product existed
That was a big noise difference. Wow!
Interesting result!
Very nice Test. I would prefer the Rear box to. Could you try it with a smaller Car like the M3?.
Great to know. I need to check if my Skis fit.
One disadvantage of the rear box with our car (EV9) is that it disables the highway driving assist (HDA). Especially because you mostly use the box on long road trips.
The whistling noise will be from the mounting system rather than the box. Usually there are plastic blanking strips to cover channels the bars fit in. Alternatively you can cover with tape.
Yeah.
There are even special rubber things to cover the holes which makes whistle noises.
Also I believe that this "turbulence" can affect the consumption
It would be interesting to see what a loaded box would be as that would change the ride height as well
There is only one issue with that rear box. In two European countries (Italy and Spain) you have to attach a 50 by 50 cm reflecting board on a rear box, even if that rear box has lights. This box is realy slim and if you attach the mandatory reflecting board to it, the license plate would certainly be covered, which is illegal again. My parents own an older Thule rear box that is slightly higher and can be mounted on the Thule bike rack. This box is about 70 cm high and the license plate is attached to the bike rack where it can not be covered by the reflecting board above.
Indeed, police stopped me in Italy and told me I should have a reflecting board on a bike rack.
makes sense that putting objects into turbulence behind you helps. recumbent bicyclists get more efficient when using an aerodynamic shape just behind the rider. regular upright bicyclists *in the front* of a peloton of cyclists get 6-14% less drag compared to when they ride alone at the same speed. (Aerodynamic drag in cycling pelotons: New insights by CFD simulation and wind tunnel testing, Eindhoven University) i imagine even the ford lightning could be made reasonably efficient with tight fitting aero attachment on the back. the trailing edge's shape is the most important thing
For mainland trips the efficiency and quietness just outweigh the no rear camera and having to park in Caravan area in services with short bays. But for trips including ferries you will probably get a surcharge for excessive length of vehicle.
thanks
Rear protuberances improve vehicle drag coefficients, there's vids here on yootoob of a subaru gaining 20% with a foam sloped back
eco flow heater earned a like regardless of any other content
Wow! Impossible! Can you do more test with different cars? ID.3 for example? 😅😊
I have a Thule 900 roof box, it's sleek, makes no noise and little consumption difference. It can carry 70 kg. If no possibility for roof box, a bigger rear box is fine (also 60-70 kg but less volume). The rear box accessibility is far better, of course (but more exposed for theft attempts as well). The rear box combined with bicycle holder is probably the best deal (they share the chassis, so you can mount either or the other). Note that e.g. on ferries the tall (up to 2.3-2.4 m) but short (< 5m) places tend to be cheaper than the longer (>5m) places. But many parkings have low ceiling limit (2.2 m or so). All in all, I'd agree the rear box is more practical in most cases.
The problem i have with this Arcos design is when storing after use its not a two-piece design but something that is a one-piece heavy unit (unlike when you first install during the setup)
Rear box will I select too.
Is the box big enough to fit a full size spare wheel?
this is all good but does it fit a big ski?
I made a rear box for my Model Y and use it often. I used a Harbor freight hitch extension so that I can open the back hatch. Just enough room to back into a Supercharger and get the power cable to reach the car charger port. Keeps the back of the car open for standard poodles 😅
Thanks for commenting on being able to supercharge. Trying to find a rear cargo box that is easy to install, and can supercharge with no problem. I’m considering this Thule arcos.
The problem with the box is that in most cars the assistance systems won’t work when you plug-in in a hitch. So roof box to the win!
I had a roof box on my polestar, but the noise and high energy consumption were killing me. I sold it, bought some aluminium plates and built myself a hook box (1850x450x450). Super solution, easy access to skis and boards, no more rubbing against the car and scratching the paintwork, zero noise and low impact on consumption. The only downside is more oversteer in corners, I have to drive a bit more carefully on slippery roads.
Yeah, well, you basically built yourself a 911 with the weight behind the rear wheels 😁
@@herrtichy I've always complained that the Polestar is too understeery in corners and that it should be the other way around, so I guess my dreams have come true :D
can you show me a photo, I am considering doing the same. how did you attach it to the tow hook?
@danpadure I used the Berger & Schröter 20215 adapter to mount the crate on the hitch. No ski seson yet, so the skibox is lying deep in the basement and it's hard to get a picture but i can look for some pictures in the archives. Where can I send them?
Would love to see photos of you box and how you constructed it. Also how did you do the hitch attachment?
After installing a roof rack on a model 3 once (scared as hell that I was creating my own roadster) I decided that I prefer to tow stuff
What is the price difference and weight limit on those two ?
With a fully loaded car I think I would like to have a roof box to better distribute the weight between the front and rear axels.
Interesting test but what about skis? They probably don’t fit in the rear box.
Could it be that the difference between no-box test 1 and 2 is wind resistance?
Is it acting like a diffuser to de
crease coefficient of drag
Why isn't there a small spirit level on the frame to make levelling it on the tow bar easy?
Can't fit 8 sets of skis in the rear box (or inside car), so roof box it is for us... But interesting test anyway, the noise and aerodynamics advantages of the rear box seem pretty evident.
I would like to get the same kind of the rear box, but for 2 bicycles placed inside horizontally ;)
Interesting test... A rearbox would be great for cars that are not allowed to tow anything and / or have a roofbox.
like the original ioniq. i have an arcos and it is great
While the box on the back looks way better in these tests, even with the lights it's not that easy to see from behind so there might be some extra risk of getting rear-ended. I think big showy zig zag hazard stickers on the box would help.
(Of course there's a risk with the roof box of hitting low obstructions above the car - like those signs that limit the height of vehicles using a car park.)
It would help a lot if there were a reversing camera actually on the rear box that could maybe send to your mobile on the dash.
Being rear ended was my concern, wonder if it's only sold in black?
Yes, it increases the risk, even with the extra lights. That´s the reason why some countries (Italy and Spain) have laws that make it mandatory to attach a rectangular 50 by 50 cm board with a reflecting white and red surface to the end of any rear box, regardless whether it has lights or not.
The big problem I see with that box is, that you simply can´t fit that 50 by 50 cm board on the rear of such a slim box. And even if you find a way to attach it, it would certainly cover the number plate which is illegal as well. So there is simply no way to legally use that specific box in Italy or Spain. That is an absolute no-go for me as I go to Italy quite often and those long trips would be the perfect case for me to use it.
Downside of the tailer hit box is that this one is actually quite heavy. The base part is 9 kg and the box (L) is 20, to 29KG. The model 3 is only allowed to have about 55kg on the hitch so you are left with only 25kg load capacity.
That's a model 3 problem. All cars I know have 75 kg allowance on the trailer hook.
@@AHBdV agree, but it good to be aware of this.
I would like to see the results of a 'Moose Test' and emergency braking tests when fully laden. My preference is for a trailer, easy to attach and remove, with a good load ability and little effect on fuel consumption.
My experience is that trailer (while mine is not that big) increase consumption quite a lot. Also would be quite horrible in moose test I guess :)
Roof box is safe up to 130km/h
What is the max speed for the rear box ?
a real problem with noise with a box on the roof only after 150 km/h, not relevant for Norway
and the box at the back requires a tow bar, increases the length, is a problem in parking and interferes with the trunk
Interesting test, but I think it is close to a worst case scenario for the roof box. A longer and slightly slimmer box would probably be more efficient. I have the Thule Dynamic 900 on my Volvo XC60 and I'm always surprized how litte it affects the consumption. Closer til 5 % increase than 10 %, at least when doing around 90-100 km/h. Doing norwegian country roads around 80 km/h it is barely noticable.
But it is more noisy, specially when it's windy.
Probably a side effect of the EV being quiet by default. Never noticed noise on an ICE except with a sunroof open
@SteveLoughran on the highway, EVs aren't any more silent than ICEs... just check the ADAC noise tests at 130 km/h. Absolutely no difference between EV or ICE. Its all a matter of wind and tire noise. In my hybrid, I need to look at the rpm counter to know if the ICE is on or off. I can't hear the difference.
Bear in mind the maximum vertical load on the tow bar for the id5 I believe it's 75 kilos and 100 kilos on the roof
.., cars differ my Honda Civic you're lucky if you can get more than 25 kilos without it causing an issue grounding.. If you put three hairy men in the back and some luggage in the boot you'd have no chance of having any towbar weight at all..., all I'm saying is consider your specific vehicle
Rear box give an advantage actually it acts like a lower rear spoiler better Areod
What capacity size was the Thule Arcos box used in the test? 300l or 400l version?
The small one.
No surprise, as also saddle backs on bicycles do actually improve aerodynamics!
can you also test the MFT Backbox. I am close to buy one but not sure which i should take. Thule or MFT
Same issue here did you get any wiser?
More frontal area + worse drag coefficient for the roofbox
vs
Filling in the void behind a hatchback
No competition
you'd likely get even better mileage with a bigger empty rear cargo box than with this low box, hanging a bit too low, or than without it
if its a choice, always go for the rearbox.🙂
All good but you should have got EcoFlow delta pro combined with their wave 2.
Way too heavy.
There's a big difference between the two though: you cannot transport skis or snowboards on the rear box, so at least here in Norway, I don't think there's much of a choice tbh.
If you have 4 people or less you could slot them through the middle seat ski hatch thing…
What about ski bars and mounting the skis upside down on them?
@@amiddled yes, but that's not what's being discussed in the vid.
@@SteveLoughran I guess that could potentially create even more noise or drag than a well-designed roof box. It's not what Bjørn tested, so I cannot say. I'm simply referring to the options he presented.
@@eddiehaug you suggested, there was no choice, I gave you an alternative…
another test carried out showing improved range with cargo box attached compared to no boxes:
czcams.com/video/3N-YOERIx9k/video.html
In desperation of getting home for Christmas with a battery driven car....OMG...I`m glad I have my 3 diesel cars 🙂
Rearbox puts pressure on rear springs only!
I am planning to get a tow hitch box for my ID.4 but am wondering how hard it will be to back to chargers on a trip? will the cables reach? Especially on Superchargers
I have a Thule Arcos that I have used on my ID4. I have only had issues once because there was a car parked next to me on the line. So couldn't get close enough. Otherwise, no issues!
@@emmajohansson3852thank you for commenting on this. I’m trying to get more feedback on supercharging with the arcos on model Ys. Surprised I don’t see more comments re this.
I'd go for the roof box, for two reasons:
• My small-battery Kona has no option for tow-hitch. Not even the 100kg vertical-load-only one the bigger-battery Kona had.
• There was a roofbox included with the offer when I was buying the car.
That being said, if there was an actual choice if I want one or the other, without these restraints, the rear box looks kind of like nicer solution. Maybe someone could offer a „hybrid“ solution that can be mounted on top or back as needed.
And there were times when I'd have used both at the same time if there was the possibility 😇
Wont the extra light activate trailer mode and disable autostear in some cars like Tesla?
Nope
It does with hitch bike racks, and I don’t see that this would be any different. However, after plugging in you can simply deactivate the trailer mode. Still wish Tesla would add a dedicated hitch bike rack mode.
What difference would adding weight to the boxes make?
My car has raised roof rails which are aero shaped,would the box fit directly to these and would they reduce the drag and wind noise?
Roof racks are bad for noise/drag usually.
I have a Thule towbar mounted bike rack which is very good.
Adding the maximum rated weight for either setup wouldn’t change the efficiency by much if at all. You’re talking somewhere around 150lbs maximum payload for either option.
czcams.com/video/ChLSfpmnNZE/video.html
Would the difference be bigger in an efficient car like a model 3/Y ?
My guess would be yes, since drive trains of efficient cars tend to obly be really efficient when no extra strain is put on while driving. See the trailer videos. Relative difference was much less, when the car wasnt as efficient in the first place. The roofbox with its big aerodynamic drag will increase consumption more since the motors will not work at their designed (most efficient) rpm-Nm window. I dont know if that makes sense, but thats what i would guess. Nonetheless the teslas will be super efficient anyways 😂
@@benzo5799 that's what i thougt as well but i can not explain why, just makes sense to me.
Nice invention. 😊 What do you think about the Tesla strike in Sweden? Will you help to drive Teslas to Sweden? Just an idea 💡 😊
Very interesting. I think if it was 1-2 trips a year, the roof box means you can go larger, fit into parking spaces/charger spaces and plan differently for more stops. If it was a regular need, the rear box is easier to fit and take off, only impacting parking, if that is a concern
Easy to forget it's there -but as any rear camera will be above it, maybe you'll be ok
Hello what is the best app to get the obd information? Thank you
Car scanner, from memory.
ABRP collects some info, including battery temperature
❤❤❤
Yes...but the hitch is for bikes 😎🚲
What would the results be with the roof bars on their own, I wonder? Possibly worse, as the roof box has at leat some aerodynamic design.
Unlikely, if you ask me. Drag of box should offset the part of the bars it covers... but its hard to say for sure, I agree.
@@GoldenCroc My gut instinct is that if you can hear it whistling, that is air being pushed out of the way, not slipped through! Put your hand out of a moving car, then turn it flat on to the wind, next 90 degrees like a blade.
I like the idea of a tail-cone box. But on my EV6 the proximity sensors would probably keep stopping the car!
@@coniow I like to think I know quite a bit about vehicle aerodynamics for not being an employed professional in the field. That being said, I think its almost impossible even for a seasoned pro to make a judgement in this case without more hard data availible.
What I can say for sure is that whistling and similar phenomenon can take an extremely low amount of energy to generate, far less than could have any effect on consumption and be measurable in a lab, never mind in the real world. Thus its not really usable as a significant marker of larger happenings in regard to airflow.
I think a few hypermilers have tried stuff effectively similar to tail cone boxes, as well as there has been a few trailer prototypes with similar function. As of now, its always been deemed to have too many drawbacks to be a succes for consumers. Maybe that will change in the future if energy is considered more valuble, we shall see. Cheers.
1:04 aren't there extension cables, that would avoid having to park like a douche? Could be a neat video, to test some of them :)
Nope
Who is your cameraman/women ?
Can you even utilize these boxes that much? Many EVs have very low loading capacity.
The ID4 GTX has up to 514kg loading capacity when a 75kg driver is already accounted for. I guess that is not to bad actually.
In the UK, you need a special license to drive a vehicle with more than 3500 kg of weight. This used to be the default before 1997 but now you need to do some extra stuff. There is an Audi Q8 etron which comes in at 3200 kg- so if you legally want to drive it with more than 4 people in then you had better update your license.
Gotta love a town called "Cleavage"!
Smooth product advertisement 😉
Too bad I didn't get money from Thule. I could need some money for the new house.
Depending on the depth of the cargo box, backing in to the charging space could be a problem. I have found about a two foot deep cargo carrier makes the charging cable lenght an issue, at least in the US with the 150KW chargers.
If they invent foldable ski's, I might consider the rear box :)
U could still do the ski's in the car and some of the luggage in the rearbox
@@johndrawing1176 unfortunately no ski hatch in a model s. And a family of 4. Anyways i dont mind some wind noise. Just happy i can fit a roofbox on my car.
I'd add a extra like if I could for the data @14:40
Roof boxes look better in my opinion. Plus i can fit skis and long items in them which you cant in a rear box. But for range/efficiency a rear box will always beat out a roof box
I mean the large version is 171 cm wide, you can definitely fit a lot of skis in that.
There is a rear box to fix skis in from MFT. But preferably I would like Thule to sell a box to fit the VeloSpace XT, to fit Skis aswell.
I think both look bad :)
Interesting…..
I should change to shorter sks!
rear box...remember ABC always be rear boxing 😂
I mean who doesn't use 3 additional heaters in their car taking up an entire rear bench?
Def rear box.
dont test 2 box at the same time ? lol