i3 BEV vs. REx from owner of both

[jadnashuanh]

Also, I didn't realize (I never priced it) that the REX option is $4k. Wow. That's a lot for a scooter motor (saw that somewhere else on this forum, may or may not be correct) and 2 gal gas tank.
(Disclaimer: That is just MY opinion.....your mileage :roll: may vary!)

There's a lot of logic and support that go with the REx, so it's not just simply the motor. FOr example, the fuel system is pressurized (maybe no fuel pump?) and even the logic to be able to open the fuel filler has to be fairly fancy with likely sensors to relieve the pressure before you can do that. THen, you have to have a new fender panel with the extra door, a different rear panel to allow for the exhaust and muffler, and some additional electronic module(s?) to make it all work, not counting the manual switch (does the NA version even have one?). But, it is what it is...if you (think) you need it, it's 'cheap'. If you really need it, it's priceless (but maybe a different car might be better!). For all of that, you get a more complex vehicle, more regular maintenance required, less EV efficiency and range because of the extra weight, a slower acceleration, and likely greater depreciation. If you can avoid it, it will save you some money, if you can't, then bite the bullet, but don't complain about the (occasional) compromises you may have - the benefits may outweigh the minuses, it all just depends.

 

[Zzzoom3]

There's a lot of logic and support that go with the REx, so it's not just simply the motor. FOr example, the fuel system is pressurized (maybe no fuel pump?

Pressurization helps maintain the fuel for long periods. Some REX owners may rarely use the gas in the tank especially in the U.S. where you can't manually turn the engine on. You may only burn fuel a few times a year, so you have to make sure that storing gasoline for weeks or months won’t affect how it burns potentially altering emissions. There is an entire new set of conditions that have to be managed and the vehicle has to know how much fuel you have, when you use it, when you add it, what the outside temperature is, etc. Heck, I think there is even a place to store the exhaust fumes when the tank gets depressurized?

Al this managed by sensors and software. Can anyone say CEL?

So yeah, lots more too it than just adding a motor

 

[Stevei3]

Also, I didn't realize (I never priced it) that the REX option is $4k. Wow. That's a lot for a scooter motor (saw that somewhere else on this forum, may or may not be correct) and 2 gal gas tank

Hi guys,

I think it was 'Ultraturtle' here who made an excellent point earlier on: $4k is actually very cheap if you're looking for a high efficiency, liquid cooled, relatively clean (catalytic converter/EURO6) and quiet 25kw gas generator...

Steven

 

[electricvirgin]

I am not sure depreciation would be worse with Rex. Given the battery performance will worsen over time on BEV and Rex alike, the range extenders greater flexibility would likely be a plus for a second owner?

Also there is a lot more competition on pure BEV cars from leaf/Zoe/Golf/Up/B-Class with none offering a range extender option that compares with the BMW, i would expect depreciation to be broadly equivalent between the BEV and Rex myself. However its all guesswork for the time being of course!

 

[jadnashuanh]

Was reading an article on the worst small car performance in the crash tests performed on cars in the USA...the Nissan Leaf got some pretty lousy results. It did not have results from the i3 in that list, and it's interesting on how the Euro tests differ. The i3 got 4-stars and the Leaf got 5. The dinged the i3 because it doesn't have standard collision and pedestrian detection - if it was standard, it would have had 5-stars. Many of the smaller cars in the USA have a really hard time with the offset pole test that's fairly new...eventually, I'd expect them to test the i3, and hopefully, it does well here in those tests.

 

[Tummy]

We do only one or two long trips, about 600 miles each way to visit relatives over Christmas in Illinois and about 450 to go to Florida. For those trips we will now only rent a car from Hertz or Sixt.

I was considering renting a car for our annual Christmas trip, but decided to drive our SUV. We drove my ML63 AMG to Illinois and made it 2 miles from my in-laws house when the transmission failed. It was on Christmas eve. We had to wait until after Christmas before it was towed to the dealer and needed a new transmission (at 48k miles). To get the part and do the repair took the dealer 5 business days, so I had to rent a lousy Toyota Camry with nearly bald tires, to drive back home, then back again in a couple weeks to pick up our SUV. We couldn't fly home because I had to drive our dog back with us.

If I had rented a car, like I was initially thinking, we would have been able to just swap it at a Hertz if something went wrong.

At ATL we can rent MB CLA250 for $37/day or X5 for about $100/day. If BMW doesn't have the alternate mobility program in the US, we'll rent this winter for our trip.

I traded that ML63 for the i3 BEV.

 

[Zzzoom3]

I traded that ML63 for the i3 BEV.

Loud Applause !!

 

[kevinb61]

Also, I didn't realize (I never priced it) that the REX option is $4k. Wow. That's a lot for a scooter motor (saw that somewhere else on this forum, may or may not be correct) and 2 gal gas tank.
(Disclaimer: That is just MY opinion.....your mileage :roll: may vary!)

There's a lot of logic and support that go with the REx, so it's not just simply the motor. FOr example, the fuel system is pressurized (maybe no fuel pump?) and even the logic to be able to open the fuel filler has to be fairly fancy with likely sensors to relieve the pressure before you can do that. THen, you have to have a new fender panel with the extra door, a different rear panel to allow for the exhaust and muffler, and some additional electronic module(s?) to make it all work, not counting the manual switch (does the NA version even have one?). But, it is what it is...if you (think) you need it, it's 'cheap'. If you really need it, it's priceless (but maybe a different car might be better!). For all of that, you get a more complex vehicle, more regular maintenance required, less EV efficiency and range because of the extra weight, a slower acceleration, and likely greater depreciation. If you can avoid it, it will save you some money, if you can't, then bite the bullet, but don't complain about the (occasional) compromises you may have - the benefits may outweigh the minuses, it all just depends.

Hehehe....yes I know....those are some of the main reasons I did not wish a REX.

It's all good! Great little car either way. Just get a kick out of the banter about what group made the better decision .
People get so sensitive if you don't agree with their view. I myself love to be one of those in the "minority", as I generally can't stand having whatever the "majority" wants.

Thank God for choice or we would all be driving Toyota Camrys (oh the horror!)

 

[cab]

I spend about 50% of my time in Europe and the other half in the USA. After purchasing the BEV in Europe a couple of months ago and loving my i3, I took the plunge last week and purchased another i3 in the USA, except this time I purchased the REx.

The first very noticeable difference I felt between the two models was the pickup; I notice a *significant* difference in the acceleration. The BEV seems to 'fly' when I hit the accelerator pedal all the way; that feeling is absolutely not the same with the REx. Based on the 0-60 speed numbers I have read on each, you'd think the difference between the two models would be almost imperceptible, but let me assure you, that is not the case. Don't get me wrong, the REx still has fantastic acceleration, but it is definitely more 'sluggish' (if you can call it that) than the BEV.

With that said, even though I don't usualy drive long distances in either continent, the REx gives me a priceless piece of mind. I feel far more comfortable not having to worry about the very limited mileage of the BEV. The REx 'insurance' was definitely worth the price to me; it enables me to enjoy my car more, giving me that feeling of freedom and knowing that I've cut that 'umbilical cord'. I now wish I had purchased the REx unit in Europe as well. I see how it would be possible for others to also regret their BEV over REx decision, but I can't picture the opposite: drivers thinking down the road 'Oh why, why on earth did I get the REx?! (when I rarely use it)".

I know everyone's circumstances are different, but with that said, I just wanted to give the forum a summary of *my* experience.

Waffle, your comment about the acceleration is interesting since I've been wondering just how different the two are. Truth be told, the acceleration of the i3 is one of the primary reasons I am considering it as a Volt replacement. Do you feel the difference in acceleration is predominantly in the 0-15 mph range? Essentially, does it feel like the extra mass just hurts the "get it moving" factor? The i3 doesn't have nearly as much torque as the Volt or Mercedes B class and I've noticed lower torque cars seem a bit more impacted by changes in vehicle weight. It shows up even just adding passengers, etc.

 

[jadnashuanh]

The i3, in either form, is significantly lighter than either the Volt or the MB B-class vehicles. The Volt does have a significantly larger ICE in it than the REx along with a larger fuel tank, so it is closer to a general purpose car since it works for a long distance cruise. I had trouble getting in and out of the Volt - I much prefer (and bought) an i3, partly because of the higher seats and bigger door opening, but also I did not need or want the combustion engine at all and kept my ICE for when the i3 wouldn't work. I think most people would notice the difference in max acceleration between the BEV and the REx if they drove them back-to-back. Most people don't use max acceleration very much, and on an EV like any car, shortens the distance traveled before adding energy back in is required in whatever form.

 

[kevinb61]

I spend about 50% of my time in Europe and the other half in the USA. After purchasing the BEV in Europe a couple of months ago and loving my i3, I took the plunge last week and purchased another i3 in the USA, except this time I purchased the REx.

The first very noticeable difference I felt between the two models was the pickup; I notice a *significant* difference in the acceleration. The BEV seems to 'fly' when I hit the accelerator pedal all the way; that feeling is absolutely not the same with the REx. Based on the 0-60 speed numbers I have read on each, you'd think the difference between the two models would be almost imperceptible, but let me assure you, that is not the case. Don't get me wrong, the REx still has fantastic acceleration, but it is definitely more 'sluggish' (if you can call it that) than the BEV.

With that said, even though I don't usualy drive long distances in either continent, the REx gives me a priceless piece of mind. I feel far more comfortable not having to worry about the very limited mileage of the BEV. The REx 'insurance' was definitely worth the price to me; it enables me to enjoy my car more, giving me that feeling of freedom and knowing that I've cut that 'umbilical cord'. I now wish I had purchased the REx unit in Europe as well. I see how it would be possible for others to also regret their BEV over REx decision, but I can't picture the opposite: drivers thinking down the road 'Oh why, why on earth did I get the REx?! (when I rarely use it)".

I know everyone's circumstances are different, but with that said, I just wanted to give the forum a summary of *my* experience.

Waffle, your comment about the acceleration is interesting since I've been wondering just how different the two are. Truth be told, the acceleration of the i3 is one of the primary reasons I am considering it as a Volt replacement. Do you feel the difference in acceleration is predominantly in the 0-15 mph range? Essentially, does it feel like the extra mass just hurts the "get it moving" factor? The i3 doesn't have nearly as much torque as the Volt or Mercedes B class and I've noticed lower torque cars seem a bit more impacted by changes in vehicle weight. It shows up even just adding passengers, etc.

BEV 0-60 is 7.2 & REX is 7.9. That kind of difference you can definitely feel (and yes I drove both before buying my BEV).

And stats aside, it should be quicker. It is not carrying a extra motor/generator combo, separate cooling & fuel systems/exhaust etc.

 

[ecoangel]

Figures from BMW: BEV 7.2 v REX 7.9 secs - half a second slower due slight weight increase and if BEV has 155 tyres all round it has a tiny drag advantage, but in normal use over say 50 miles there's no real difference.

Best way to test acceleration is to drive one after the other on same width roads in same conditions. I think most of the REX feels slower argument is subjective and in this case tested in EU v USA where road sizes and average car sizes can be significantly different!

If you drive 100 miles a day REX makes more sense especially in winter. If you drive a lot more than that or live in a very hilly area, then you might be better off with a diesel.

Whist it's fun to drive in one gear ratio and beat all at the lights (my racing 1969 Lancia Fulvia can achieve 40mph in 1st) , the BEV is best at city driving and i3 in general is designed for under 40 mph average given it's girth and poor Cd.

 

[kevinb61]

Figures from BMW: BEV 7.2 v REX 7.9 secs - half a second slower due slight weight increase and if BEV has 155 tyres all round it has a tiny drag advantage, but in normal use over say 50 miles there's no real difference.

Best way to test acceleration is to drive one after the other on same width roads in same conditions. I think most of the REX feels slower argument is subjective and in this case tested in EU v USA where road sizes and average car sizes can be significantly different!

If you drive 100 miles a day REX makes more sense especially in winter. If you drive a lot more than that or live in a very hilly area, then you might be better off with a diesel.

Whist it's fun to drive in one gear ratio and beat all at the lights (my racing 1969 Lancia Fulvia can achieve 40mph in 1st) , the BEV is best at city driving and i3 in general is designed for under 40 mph average given it's girth and poor Cd.

Well, the feels slower argument is not subjective, it is fact. A 1/2 sec 0-60 difference is noticeable. Whether one cares is another thing. And the 40mph average is hogwash. I use it on the freeway constantly in wind (live by the Ocean in Northern California). Is it as stable as my '11 Z4? No (duh), but it drives 70-75 all day long with very little wander (at least my BEV does). Most of it's "girth" is below centerline of wheels (battery pack of course).

 

[WaffleHouse]

I spend about 50% of my time in Europe and the other half in the USA. After purchasing the BEV in Europe a couple of months ago and loving my i3, I took the plunge last week and purchased another i3 in the USA, except this time I purchased the REx.

The first very noticeable difference I felt between the two models was the pickup; I notice a *significant* difference in the acceleration. The BEV seems to 'fly' when I hit the accelerator pedal all the way; that feeling is absolutely not the same with the REx. Based on the 0-60 speed numbers I have read on each, you'd think the difference between the two models would be almost imperceptible, but let me assure you, that is not the case. Don't get me wrong, the REx still has fantastic acceleration, but it is definitely more 'sluggish' (if you can call it that) than the BEV.

With that said, even though I don't usualy drive long distances in either continent, the REx gives me a priceless piece of mind. I feel far more comfortable not having to worry about the very limited mileage of the BEV. The REx 'insurance' was definitely worth the price to me; it enables me to enjoy my car more, giving me that feeling of freedom and knowing that I've cut that 'umbilical cord'. I now wish I had purchased the REx unit in Europe as well. I see how it would be possible for others to also regret their BEV over REx decision, but I can't picture the opposite: drivers thinking down the road 'Oh why, why on earth did I get the REx?! (when I rarely use it)".

I know everyone's circumstances are different, but with that said, I just wanted to give the forum a summary of *my* experience.

Waffle, your comment about the acceleration is interesting since I've been wondering just how different the two are. Truth be told, the acceleration of the i3 is one of the primary reasons I am considering it as a Volt replacement. Do you feel the difference in acceleration is predominantly in the 0-15 mph range? Essentially, does it feel like the extra mass just hurts the "get it moving" factor? The i3 doesn't have nearly as much torque as the Volt or Mercedes B class and I've noticed lower torque cars seem a bit more impacted by changes in vehicle weight. It shows up even just adding passengers, etc.

Absolutely - I would say the difference in acceleration is predominantly in the 0-15mph range.

 

[cab]

As an aside, I posted some of the Car and Driver i3 vs. B Class Electric (in this month's C&D...won;t be online until next month) stats on the Volt forum: http://gm-volt.com/forum/showthread...ectric...0-60-stats-etc&p=1800314#post1800314

BMW sandbagged their official numbers (as usual), and the B class was considerably quicker than expected

An excerpt (note: the VOlt was not tested in this comparison, I just dug up the old stats):

0-60
6.5 secs - i3
6.8 secs - B class
9.2 secs - Volt

1/4 Mile
15.3 @ 86 mph - i3
15.4 @ 92mph - B class
17.0 @ 82 mph - Volt

Top Gear 50-70 mph
4.1 secs - i3
3.8 secs - B class
5.7 secs - Volt

 

[cab]

waffle - have you noticed and difference in the ride quality between the rex and non-rex? I'm wondering if the Rex's additional weight makes the ride any better or worse? I know you can't exactly do back to back test drives.