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Range loss with roof racks?

Range loss with roof racks?

I'm still waiting for the Model 3 to be made available in a right hand drive edition, but whilst I wait, I was wondering.

Does anybody here have the roof racks that Tesla sold for the M3? And if so, can you give an indication of the range hit they give, preferably with a couple of bicycles loaded up there? This is the only significant concern I have about the Model 3: how much range I can expect to get if I need to load my bike(s) onto the roof rather than loading it internally. The approximate percentage hit will determine whether I can get away with the standard range, or if I need to go for the medium/long range model for my expected needs (the Supercharger network will be fine for a roughly 250km range vehicle, which is a roughly 30% drop in range from the standard model; if the drop is more than 30%, I'm in trouble and will need a longer range vehicle.)

Many thanks.

M3phan | 27 januari 2019

No discernible range loss according to this one user, https://m.youtube.com/watch?v=4tXnmYRCy4o , the percentage increase in consumption between the roof alone versus the roof with bike rack installed is just 2% increase in consumption. He has a margin of error of ~2% so no real difference. He also ran tests with the bike rack and a storage pod. Check out his video, with various results on a chart at the 16 minute 25 second mark.

PECo CT | 27 januari 2019

There are so many variables that could affect your range that you should probably get the longest range model you can.

Correct me if I’m wrong, but I think that Tesla expects a Model 3 to use approximately 240 Wh/mi. Over the first 1,500 miles on her Long-Range, Dual-Motor, my wife has been averaging 389 Wh/mi. However, that has been mostly in the cold of a northeast US winter, on winter tires, over hilly terrain and over a short 32-mile round-trip daily commute and very local driving.

In any case, our expectation was that we’d have to adjust to the limitations of the new technology and, so far, those limitations haven’t hurt our enjoyment of the car at all.

sjl | 27 januari 2019

PECo CT: that's a question of money. Going with the long range M3 is likely to push me into a price above Australia's luxury car tax threshold (an extra 33% on a GST-inclusive price above $AU75,526 - so there's no LCT payable on an $AU75,526 vehicle, but an extra $33 luxury car tax on a vehicle that costs $AU75,626, for example - the latter would then come up to $AU75,659.) Pricing is yet to be fixed, but my guestimate is that the base model 3 will go for around $AU60k, and the long range will be around $AU80k before LCT. That's going to be a major stretch for me; I can probably do it, but it won't be the slam dunk that it would be if I could get away with the base model.

If money were no object, I'd just go the long range model and be done with it. But it is a concern, so there's a desire to try to figure out just how far I can go in shaving costs before I end up with a vehicle that won't suit my needs.

As for that video, it's comforting, but not quite comparable to my use case - he's using an enclosed box, which is probably going to be more aerodynamic than my bicycles. Any data is useful, don't get me wrong, and it eases my uncertainty a little... it'd just be more useful to be able to compare apples to apples. (He shows that he's traveling at 100 kph, so my concern about the major hit that occurs at high speed is significantly diminished, which is a good start.)

Thanks.

M3phan | 27 januari 2019

Apologies but I might be misunderstanding your question. Actually he does test with the roof rack alone without a pod. his tests were of three variations: plain roof, roof rack alone, then roof rack with pod. His test with roof rack alone was the 2% decrease efficiency. Roof rack plus pod was 12% decrease efficiently.

Bighorn | 27 januari 2019

I’d say 15% based on others’ reporting.

mrburke | 27 januari 2019

@Bighorn - 15% ? Is that the bare rack, or the rack with something on it, like a Bike or Pod ?

Bighorn | 27 januari 2019

I was referring to carrying a couple bikes.

my2cents | 28 januari 2019

Kootenay EV family video and results are for roof box, not bicycles. Surely there are some tests out there, but then perhaps not with the Tesla roof rack. BTW - seems only a handful of these racks were sold and now no info for months - have they pulled the plug on it due to fiddly installation and glass issues?

Kathy Applebaum | 28 januari 2019

Based on my Leaf, I'd expect 10-15% loss for having a couple of bikes up there.

sjl | 28 januari 2019

~15% range loss sounds about where I'd expect it to be, and if that's all it is, there shouldn't be a huge concern for me. I'd still like to see firm sources, but it's a starting point at least.

Thanks all.

coleAK | 28 januari 2019

From my experience of 30+ years carrieing a ton of differant things on roof racks: skis, cargo boxes, bikes, RTTs, ... and given our experience with a Tesla for 4 years (s then 3). With 2 bikes on a fork mount loaded around town driving very little effect. Now highway >55 mph, I would expect a huge noticeable difference 20-30+% wouldn’t surprise me. A wheel mount would make it worse. I get ~20% worse MPG in my pig of an LX 570 when I have two Yakama skyboxes on top. If your worried about range and bikes do a 2” receiver and hitch rack. Hitch bike racks are way easier anyway. I switched 5 years ago makes me wish I’d done it years ago. Now I only put bikes on the roof if hauling >4.

Earl and Nagin ... | 28 januari 2019

Given the extreme aerodynamic efficiency of the Model 3, I would expect significantly higher percentage of range reduction than @coleAK and @Kathy Applebaum have experienced on conventional, inefficient vehicles.
Remember that if the car uses zero energy to travel, the drag caused by something else will be 100% of the drag but cause infinitely worse range.
I would, as a SWAG, assume twice as much % reduction as the above have suggested or between about 20% and 50%. If you get better performance, you can celebrate.

Bighorn | 28 januari 2019

teslamotorsclub.com/tmc/posts/831045/
13-28% more in this experience depending on speed. Agree it would be proportionately more in the higher efficiency Model 3.

limfamily | 4 maj 2019

@coleAK

I too was wondering about this. I was debating between putting a roof rack on our Model 3 vs getting a hitch rack on our Model X. After reading your post, I am skipping Model 3 roof rack and opting for Model X hitch rack instead.

Thank you for your post.

coleAK | 4 maj 2019

@limfamily. Your welcome. You’ll be much happier not dealing with getting bikes on and off the roof. I put a Stealth eco hitch 2” receiver on the 3 haven’t used it with the bike rack yet but it’s ready to go.

Tuning In | 4 maj 2019

I’ve been using roof racks for my bikes and cargo boxes for decades. I’ve always seen a 20%-35% increase in consumption. I don’t see why it would be any better with the Tesla. Sold all of my roof mounted stuff and replace everything with hitch mounted.

lilbean | 4 maj 2019

@coleAK Who installed your hitch? Thanks!

Tesla2018 | 4 maj 2019

I get 30 mpg as compared to 33 (10%) with the roof off on my Lotus which is similar in design to the Roadster. And the back window that the air hits against instead of going over the roof is only about 5 sq ft.

CharleyBC | 4 maj 2019

@coleAK: Did you find the Stealth installation difficult to do? I admit to feeling shy about embarking on the rather substantial-looking disassembly required. Any gotchas?

vswendsen | 4 maj 2019

CharleyBC, If you go to the Stealth Hitch web site they have installers that they recommend. I used one of them. There are different hitch packages you can get and I got the one with the brake light connection. That gets connected somewhere near the frunk and there was no way I was going to attempt that myself.

amer | 26 maj 2019

As a data point - comparing a trip I did in August 2016 vs May 2019, both trips done with the same Model S on the exact same route (~90 miles):

August 2016, family of 4, loaded for a long distance road trip, outside temp 77-82, inside temp 69, average speed 56, top speed 75 = 299 Wh/mile

May 2019, family of 4, loaded for a camping trip, with 2 bikes on a upright roof rack and a 5G water carrier on Thule square roof rails, outside temp 79-89, inside temp 69, average speed 74, max speed 80 = 549 Wh/mile

So, that's 43% range loss from a combination of temperature change, roof rack and gear and speed. I think the roof rack contributed the most - I'm not sure about how much the software accounts for with temperature and speed, but it definitely was getting thrown off by how inefficient the roof rack was making it and had very bad range estimates that I had to second guess using abetterrouteplanner.com

jayratch | 20 augusti 2019

Any chance anyone has tried a Model S with kayaks on the roof? I’m a whitewater kayaker and I usually have two boats on my roof, essentially at all times. My primary use of the car would in fact be for kayaking trips which I currently drive in a Sprinter van. I noticed a drop in efficiency of about 20% putting racks and kayaks on the Sprinter, which like the Tesla is designed to minimize drag. If it’s just a 20-25% reduction then that would bring my range down from the advertised 370 miles to still almost 300, more than enough to get between Superchargers around most of the country. But if it’s much more of a reduction than that, I should reconsider whether a Tesla is right for me.

surfpearl | 20 augusti 2019

Wrong forum, but with your use case I'm sure Tesla will be right for you even if the efficiency drops by ~30%. Best to rent one with a roof-rack and go on a long test drive with your kayaks loaded to see for yourself. Then you'll realize it's not only the efficiency that matters and you'll gladly accept whatever numbers you get. I carry similar loads on my Model 3, hardly concerned with the efficiency loss.