Thread: Personal EV journey.

Originally Posted by BobL

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I did the trip without a spare tyre but admit I was pretty nervous at first but then with roads in such good condition this did help ease my mind a bit. I could borrow a spare wheel from the Tesla club for these road trips but the pick up and drop off aspect would be a PITA for shorter tripe, and the 21" wheels take up a lot of space and are very heavy, so I've decided to buy my own space-saver spare wheel. Of course it has to deal with the large brake callipers of the Model Y performance Tesla, so of course it has to be special. The one I've ordered comes in a kit with a reasonable (2T) jack, jack puck (so's not to damage the vehicle) and telescopic/extendable wheel brace and 21mm socket, and pair of gloves and safety triangle, all in a decent ripstop nylon bag. This wheel also fits in the under floor storage section of the rear compartment which is distinct positive. Speed is limited to 80 kph but that's a lot better than being stuck in the middle of nowhere. Price is of course commensurate with the price of the tow hitch only $895 plus $27 postage. Cheap right? I'm now resigned not to expect anything less

The space saver are tyre has arrived.
The seriously solid alloy wheel is much sturdier than all other space saver wheels I've seen and the tool kit appear to be very good quality, but at the price paid I would expect nothing less,
The wheel also comes in a sturdy rip stop nylon bag with decent handles which makes it easier to carry.
There is supposed to be a way to store the wheel in the Large storage space under the rear cargo compartment floor but haven't worked out how to do this yet.
The space under the floor of the rear cargo compartment is also required to store changing cables and the tools so I'm not going to place the wheel in the vehicle except when I leave town.
TeslaSpaceSave.jpg

Bob - at least you have the option ! I know many BYD owners in rural areas aren't happy with the "Goo+Pump" repair kit that comes with the Atto 3, and BYD don't offer any factory solution for a proper space-saver spare. Then some resourceful Atto 3 owner somewhere discovered that the space-saver spare for the Toyota Rav 4 was a perfect fit in terms of wheel size and fixing pattern, so these have been in high demand ever since.....

question for "BobL" and "Mr Bush"
If Teslas, Atto 3s, BYDs are supplied -- in standard configuration -- without a spare tyre, are the vehicles fitted with Run Flat tyres?
As far as I know, those BMWs that do not come with a light weight spare are fitted with run flats as standard.


I understand that Tesla's -- at least in the US and Canada -- come with full roadside assist, meaning that Tesla will dispatch a spare tyre or flat top tow truck to wherever the vehicle has suffered a flat and carry the vehicle to where a spare can be fitted.
Is the same true in Australia?

All BYD Atto 3s in Australia are NOT supplied with run flat tyres. In fact, they are supplied with a spectacularly cheap and crappy normal tyres (Batman brand) which offer such poor grip that several owners have changed them out for a better tyre even from new (before they wore out). EVs generate massive torque from standstill, Atto 3 is front wheel drive, so tyre quality does matter. The car is supplied with a repair kit containing a sealant goo plus a compressor to re-inflate the tyre. Of course, this generally only works for small punctures , so if you damage the tyre sidewall you will be left relying on roadside assist. Hence some more creative owners, travelling off the beaten track, finding their own space-saver spare from Toyota Rav 4. To be fair, Atto 3 fits into that increasingly popular category of car which looks like an SUV, but should never actually venture off sealed roads......

Originally Posted by BobL

Yesterday I did my road trip to Wyalkatchem.
426 km all up for 96% use of battery which is consistent with the 176 W/km reported by the cars computers.
Watts/km is very sensitive to speed - by driving a bit more conservatively this would improve the range.
Rain and fog on the way up for about half the way, rain for about a 1/3rd of the way back.
Road was wet most of the way but in really good condition - I only saw one obvious small pothole easily covered by the big tyres.

Bob,
did you manage any recharge at the Wyalkatchem Men's Shed? or did you do the out and back trip without a recharge?

my concern regarding your "rubber band" tyres is not their width 275mm(?), but their low (35%) profile. At a profile of 35% there's not a lot of air between any pothole and the tyre's rim.

Originally Posted by BobL

Vehicle sticks to the road like it's on rails, recommended curve speeds can comfortably be taken at 20+km over recommendation, even on wet road - I wouldn't do this on even a lightly flooded road.

The 19in, 245/45 tyres fitted to my X3 perform similarly. As a general rule, I don't need to slow (from 100 km/h) for any corner posted with an advisory speed of 75 km/h or greater.
I would expect your 275/35 to have even better grip.

you do know that "advisory speeds" are based on driver comfort and not a vehicle's road holding ability?
The tool used is a "ball bank indicator" that measures centripetal (sideways) acceleration of the vehicle -- which roughly translates to how far a diver will slide sideways on a bench seat.

Originally Posted by BobL

Down side is big tyres do make more rod noise than I expected - its not uncomfortable but because the vehicle is so quiet at low speeds its a tad annoying that it's not as quiet at 110.

are you really sure that the road noise is associated with the "big tyres".
My experience driving around 70,000 km / year (in Canada) -- using summer and winter tyres -- is that a tyre's tread pattern is the overwhelming factor affecting road noise heard inside the vehicle cabin. Neither width -- my summers are on 19/245 rims, the winters on 18/235 rims -- nor profile has any noticeable effect.

Originally Posted by BobL

One thing I noticed is the almost zero buffeting of the vehicle when approached by large fast moving vehicle travelling in opposite direction on narrow roads. Normally I grip the steering wheel a bit tighter when approached by big vehicles like this but this is not needed in this vehicle. I guess this is because of the weight and very low air resistance of the vehicle. Even the series of triple trailer prime movers I encountered didn't seem to do much.

what vehicle were you using for your country driving before you bought the Tesla?
Your new Tesla might be a bit heavier, but its aero shape should make a huge difference in how the vehicle handles buffeting from oncoming traffic.

I did some charging at the Wyalkatchem shed, starting out with 98% of battery - added 12% at the Wyalkatchem shed (It turned out they did not have 3P but did have a 15A socket) and arrived home with 14%. According to my my brother when the battery says zero you have about 50km left but I did not wish to confirm this.

The vehicles we've towed trailers and camper vans with in the past have been, a Mitsubishi Van, Mitsubishi Veradas, various Subaru Foresters (petrol and diesel versions), HiAce van (I still have this vehicle) and recently an Isuzu MUX (Amanda's last vehicle).

However the Tesla went around corners I felt way safer than any of our previous vehicles although the Subarus were also pretty good at cornering. The only comparable vehicle I owned that came close to the Tesla at cornering was my Alfa GTV that I had in the 1970's, and various Alfa/Lancia/Fiats hired in Europe.

Road noise. I agree the tread pattern is a component, but whatever the causes the more tread pattern in contact there is with the road the greater the noise.
The 'Zero P40" Pirelli tyres on the Tesla are touted as low noise tread pattern tyres so there must have been other factors involved

In a 2013 study undertaken by a team of Austrian Engineers on the causes of tyre/road noise the following noise contributions were determined.
see https://ris.utwente.nl/ws/files/5465799/Bekke06.pdf
Unfortunately tyre width was not tested presumable because it would be linear with width.
Screenshot 2023-07-21 at 5.48.56 am.png
Tyre road noise is a big issue but the tyre itself is a minority component because the road itself (roughness and sound absorption) contribute most of the noise,
Tread pattern only contributes ~10%.

On reflection I remember the effect of road roughness was quite marked because some sections of (smoother) bitumen were much quieter than others.
I'm taking 2 sisters to Busselton today (436km round trip) where they have a 50kW charger next to the pub we're having lunch in with relatives that live down that way.

The trip to Busselton went very smoothy. All up 456 km at 173 W/km, not that different to the Wyalkatchem trip @ 176 W/km..
Some light showers but great road and time went very quickly with two sisters nattering all the way on all sorts of topics.
The main difference between this and the Wyalkatchem trip was that the Busselton trip was done at higher speeds, fewer hills and much fewer bends ..
Traffic was light so managed to sit on 111 km/hr for the much of the way.

Recharging to 80% at the 50kW charger in front of the Busselton jetty was done in quicker than the time taken to have lunch.

BobL, I'd bet the cabin noise is non-existent without the engine revving and roaring

Must be nice.

Originally Posted by woodPixel

BobL, I'd bet the cabin noise is non-existent without the engine revving and roaring

Must be nice.

Unfortunately this is not always so - as I mention above, at speed (ie above 90 kph) the tyre-road noise on some rough surfaces becomes noticeable and I find it annoying because it is so quiet at lower speeds eg at 60kph or on smooth surfaces. . It is especially noticeable at 110 when the bitumen changes from rough to smooth and back again.

I have an 7.9m long, single width car, carport, that I was hoping to fit my 5x8, long drawbar trailer (4.04m total length) and new vehicle (4.75m) completely under.
As you can see the combined lengths are 890 mm too long.

Trailer1.jpg

I was hoping the car's rear underside would be high enough so I could back over the trailer coupling but alas all that gets me is about 250mm before it makes contact with the underside of the vehicle.

I invited my brother in law around for coffee and to look at possible solutions and he suggested,
- standing the trailer up on its backside with a winch, but it's too tall for the available carport roof height (3.6m).
- hinging the drawbar so it would fold up - ie a lot of work. As a highly skilled metal fabricator and welder, I have no doubt he would do an great job but then it should probably go over the MVD pits etc

Finally he said - "What's under the paving?". and I said an old red concrete drive way, so he suggested removing a few bricks so the drawbar would nestle below the level of the bricks like this.

Trailerposn5.jpg

Vehicle can now be backed all the way in.
Trailerposn2.jpg

The coupling handle clears the underside of the car by about 10 mm
Trailerposn4.jpg

I can back it in further than this but this about as far as I want to go, so as to leave enough room so that the vehcile rear hatch can be opened to let the dogs in and out.
Trailerposn1.jpg

Bob

Is that lateral thinking or vertical thinking? Either way, a good outcome at zero cost.

Regards
Paul

Definitely "A Cunning Plan"

Some interesting comments from an Atto 3 owner on one of the (many) BYD facebook forums, re. trailer towing. He found a big increase in power consumed just while towing an empty and fairly lightweight trailer due to increased wind resistance, and the power used didn't go up by much more even with the trailer loaded. Obviously this would vary depending on the terrain, e.g. hauling a heavy trailer mostly uphill, but on the flat wind resistance seems to dominate.

The religious theory of "Intelligent Design" is all very well, but why did God give the tortoise a drag coefficient of 0.01? #crappy_engineering

Originally Posted by Mr Brush

The religious theory of "Intelligent Design" is all very well, but why did God give the tortoise a drag coefficient of 0.01? #crappy_engineering

Not that I believe in "Intelligent Design" but water based tortoises do need to swim and given their relatively small feet/paddles a streamlined shape must help.