Why the BMW i3-REx

Did I mention, my 1966 VW MicroBus "… always carried spare parts, tool box, and repair manual." When something breaks, a little voice inside my head says,"Yippie, I get to fix it!!"

I had considered the Leaf but only as a project to add a range extender engine, possibly on a small trailer or on a receiver hitch platform. But there are degrees of kluge I won't go.

This is something Nissan needs to engineer especially if they want to sell them in the 'fly over states.' Nissan needs a Leaf+ with an efficient heat engine that generates enough power to sustain the car at 75 mph on a standard day. Integrate the engine with the car and the sum is more than the parts. Include a full-power, 120/220 VAC inverter, and I'll put down a deposit. It becomes a 'power wall' that can drive on the Interstates.

Bob Wilson

 

PERFORMANCE

• 746W (1 hp) assumed vehicle overhead based on Prius metrics. Needs to be measured.
• 18.7 kWhr usable pack capacity - rated at 22 kWhr but BMW specs show 18.7.
• EPA roll-down coefficients
• EPA lists the battery range as 72 miles, speed unknown

It turns out that 'mi/kWhr' is built into the car displays so:

	mph(kph)	mi(km)/kwHr	eMPG	Route	Comments
1	20(32)	9.3(14.9)	181.1	10 mi loop	9.0 expected
2	30(48)	7.5(12)	146.2	10 mi loop	8.1 expected
3	39.1(62.5)	5.8(9.3)	113.1	10 mi loop	6.8 expected
4	52.6(84.2)	5.1(8.2)	99.5	Lacy Springs - DQ	5.5 expected

	mph(kph)	MPG	Route	Comments
1	55(88)	44.5	Bridgeport TN - HSV	pump
2	65(105)	40.5	Knoxville TN - Cleveland TN	pump

Hill climb and descent, 525 ft (160 m) @20 mph, 8% grade:

	up/down	starting SOC%	ending SOC%	mi(km)/kWhr
1	up	50.5%	46.0%	1.7(2.7)
2	down	46.0%	48.5%	+99.9(+160)

The performance data suggests there may be an alignment problem. The low-speed was better than expected suggesting a lower electrical overhead. But as the slow speeds increased, the error went the wrong way. But upon reaching higher speeds, it started approaching the expected value.


The vehicle history reports one tire replaced early. The driver side tire was not and I found the inner tread is down to the wear bars. I will get with Firestone and see if they will sell me a 'life-time alignment' on the car and perhaps discount from the 03 Prius that we no longer own. Then I'll head over to BMW later this week to see if they will do any warranty coverage on the bad tire.

Bob Wilson

ps.

. . . trying to point Bob towards used Leafs since they have such crappy resale value. But alas, they're pure BEVs and have no engine... so that doesn't work for everyone.​

Fair enough as I did test drive a Leaf. It is a nice urban car but my hard requirement, 120 miles to Nashville without stopping, made the Leaf impractical.

My normal commute is 10 miles and in the BMW i3-REx, it takes about 10% of traction battery capacity. This morning I left with 100% and arrived at 90%.

I'm also finding that I am starting to drive more at the 'head of the pack.' I have the power and regen is very effective in preserving energy. It is getting a little competitive out there and I'm a player.

With free public chargers, I begin to feel like Jonathan Livingston Seagull. I just drove from one lunch place with a high capacity charger to Whole Foods because they have a tastee double espresso $2. I also plugged in the i3 when I got there not because I had to but because I could.

Resetting the trip meter, I'd driven 85 miles, all electric, using public chargers and topping off at home on a 10A, L1 charger. Started the day with 100% SOC and down about 8% driving my usual Prius route and style. The only curious pattern is the automatic cruise control yesterday and today did not work initially. It worked in 'fixed' speed mode but in about 3-5 miles, it would work in automatic cruise control mode ... hummmm.

Guess I should show what it looks like:

Gettin' free electrons in a parking space near the shops. But the building behind charged $2.50 for a glass of club soda that is free anywhere else.

Bob Wilson

 

My understanding is the 'coding' is reversible but the car is getting the wheels aligned so it will take a while to test. Since I've figured out how to trigger the failure at will, I can quickly rule it in or out.

BTW, here is the initial alignment test:

The service tech thinks rotating the tires will give another 10,000 miles. I disagree but will wait for Alabama registration before ordering the replacements. This will be 'good enough' for now. Their estimate is $900 for the tires and I think that is reasonable ... this year.

On way to dealer, got a call that they have to keep the car through Monday because 'we have to replace the rear tires.' I told them to order the front tires and we'll make them all new rubber.

Bob Wilson

It is Friday night and I already miss my BMW i3. Sure, the Gen-3 Prius is in the driveway and I have chores to run tomorrow but I LIKE my BMW i3.

Bob Wilson

 

I was expecting a tire replacement delay but on my schedule without holding the car. My plan was to order the tires in a couple of weeks after the registration was done and then bring the car in. The 'surprise' was the 2PM call that the rear tires had to be replaced when at 9AM the service tech (a 'secretary') reported they could be rotated.

The real disappointment was having the service tech at the Charlotte BMW dealership lie to me "there is 8 mm of tread depth." When I saw the tires, I knew he'd lied which means I could not trust anything he reported. But learning the manufacturers warranty still applied in Huntsville softened 'the sting.'

These two BMW service centers are not alone as two weeks earlier I let the local Toyota Service Center replace a burnt out head light and change the oil. I was there at 7:00 AM when they opened yet it took most of the day and the standard Toyota practice:

1. Called asking to add $40 cabin air filter change. (there will always be a call!)
   
2. Added an extra quart of oil.
3. Let the air out of tires and reset tire pressure sensor. (left it that way for next service)

I had ordered a pair of replacement tires to drop ship to Firestone and expected them by the end of the week. So I left the tires at 'Toyota pressure' and drove that way for the rest of the week since I knew Firestone would do the same. The ride did not improve as much as the car no longer coasted worth a dang.

I left the car at Firestone Friday evening but when I walked the dogs over Saturday morning, they said it would not be ready until that afternoon. Once it was ready, I borrowed their air hose to fully inflate the tires and reset the tire pressure level. Gosh the Prius rolls easy with fully inflated tires.

I'm not blaming the two BMW service centers any more or less than the local Toyota or Firestone service centers. Rest assured, I won't take my repeat business to the Charlotte BMW dealership and I'll trust them all as much as the Charlotte liar.

If you want the job done right and on time, do it yourself! ​

Bob Wilson

Well it is Wednesday afternoon and they are still fiddlin' with it. When they told me the vehicle warranty was to 2019, I didn't realize a year of it would be in the shop.

Actually I suspect the first owner didn't really keep the car current and part of the extended stay is catching up on software upgrades and a curious 'motor mount bolt' (both electric and engine) issue. It seems there have been a rash of broken motor mount bolts described: BMW i3 Forum • View topic - Engine mount broken

This is unfortunately a known issue, although usually it is caused by someone accelerating while one wheel comes off the ground-such as going over a pothole or speed bump, turning over a large lip, etc. The one wheel spins to max speed almost instantly, then when it touches down again all that force causes the drivetrain to rock to it's max position. If this is done repeatedly or in a severe enough manner, it causes one or both of the drivetrain mounting bolts to shear, allowing the drivetrain to move too far and causing damage to other parts around the drivetrain such as A/C lines, wires or modules.​

I'm remembering the 'brake pause' problem we had with the early Gen-3 Prius and began to wonder if that might have happened to some of the Prius community.

Bob Wilson

 

I'm already planning my next set of benchmarks. First the 20, 30, and 40 mph tests. Then there is the overhead test.

I've also got a cross country test drive to Tunica the 19th.

Bob Wilson

 

I've wanted to compare the BMW i3-REx, Volt, and PiP but felt I wasn't qualified. Fortunately, someone else did:

		BMW i3 range Extender	Vauxhall Ampera Positiv	Toyota Prius Plug-in
1	On the road price/total as tested (including govt grant)	£28830/£35370	£28750/£29745	£28245/£30240
2	Residual value (after 3yrs/36000)	£9860/34.2%	£9833/34.2%	£10564/37.4%
3	Depreciation	£18970	£18918	£17681
4	Annual tax liability std/higher rate	£338/£676	£337/£674	£332/£664
5	Annual fuel cost (12k/20k miles)	£1089/£1814	£989/£1649	£1402/£2337
6	Ins. group/quote/road tax band/cost	21/£383/A/£0	20/£459/A/£0	16/£413/A/£0
7	Cost of 1st/2nd/3rd service	£375 (5yrs/60k)	£115/£277/£115	£119/£189/£119
8
9	Length/wheelbase	3999/2570mm	4514/2685mm	4480/2700mm
10	Height/width	1578/1775mm	1439/1787mm	1490/1745mm
11	Drivetrain	Electric motor/2cyl in-line	Electric motor/4cyl in-line	4cyl in-line/electric motor
12	Generator/engine capacity	647cc	1398cc	1798cc
13	Peak power/revs	168/0 bhp/rpm	148/5000 bhp/rpm	132/5200 bhp/rpm
14	Peak torque/revs	250/0 Nm/rpm	370/250 Nm/rpm	142/4400 Nm/rpm
15	Transmission	Single speed auto/rwd	Single speed auto/fwd	CVT auto/fwd
16	Fuel tank capacity/spare wheel	9 litres/repair kit	35 litres/repair kit	45 litres/repair kit
17	Boot capacity (seats up/down)	260/1100 litres	300/1005 litres	443/1120 litres
18	Kerbweight/payload/towing weight	1315/415kg	1732/268kg	1450/390kg
19	Turning circle/drag coefficient	9.9 metres/0.29Cd	10.9 metres/0.28Cd	11.0 metres/0.25Cd
20	Basic warranty (miles)/recovery	4yrs (50000)/3yrs	3yrs (60000)/1yr	5yrs (100000)/1yr
21	Service intervals/UK dealers	Variable/44	20k miles (1yr)/24	10k miles (1yr)/184
22	Driver Power manufacturer/dealer pos	15th/24th	26th/18th	9th/3rd
23	Euro NCAP: Adult/child/ped./stars	86/81/57/4	85/78/41/5	88/82/68/5
24
25	0-60/30-70mph	7.2/6.5 secs	9.4/8.2 secs	10.4/10.4 secs
26	30-50/50-70mph	2.3/4.2 secs	3.4/5.5 secs	4.0/6.3 secs
27	Top speed	93mph	100mph	112mph
28	Braking 70-0/60-0/30-0mph	52.9/38.3/9.5m	50.3/35.7/9.2m	52.4/36.7/9.9m
29	Noise 30/70mph	64/73dB	57/68dB	60/72dB
30	Overall Auto Express economy	65.7mpg/14.5mpl	72.3mpg/15.9mpl	51.0mpg/11.2mpl
31	Govt combined economy	470.8mpg	235.4mpg	134.5mpg
32	Govt combined economy	103.6mpl	51.8mpl	29.6mpl
33	Actual/claimed CO2/tax bracket	99/13g/km/5%	90/27g/km/5%	128/49g/km/5%
34
35	Airbags/Isofix/park sensors/camera	Six/yes/£790/£790	Eight/yes/yes/yes	Seven/yes/no/yes
36	Climate control/leather/heated seats	Yes/£2000/£260	Yes/yes/yes	Yes/£1500/yes
37	Met paint/adaptive LEDs/keyless go	£530/£710/yes	£525/no/yes	£495/yes/yes
38	Sat-nav/USB/DAB radio/Bluetooth	Yes/yes/yes/yes	No/yes/yes/yes	Yes/yes/no/yes
39	Stability/cruise control	Yes/yes	Yes/yes	Yes/yes

• Length/wheelbase - the smallest means it can park in more places and zip around the city more easily.
• Height - this means we sit higher to see over the roofs of other cars and down to the front to gauge parking. However, it can have more high-speed drag if one is spending too much time on the highway.
  
• Generator/engine capacity - the smaller engine weights less and is right sized for level cruise. Higher power should ALWAYS come from the traction battery for limited durations such as climbing a hill. Furthermore, hill climbs should always be at the same speed as semi-trailer trucks.
• Peak torque/revs - should always be at speed zero especially when towing.
• Kerbweight/payload/towing weight - lighter body car means more available for stuff.
• Turning circle/drag coefficient - smaller is better for city driving. The Cd is only important for highway driving and that is NOT what this car will be doing a lot of.
• Basic warranty (miles)/recovery - USA is 4 years and my used BMW warranty extends to 2019!
• 0-60/30-70mph - time for a car that can 'play with the big boys' and reflective of the higher power-to-weight ratio.
• 30-50/50-70mph - no slouch when having to pass cars on two-lane highways. Less having to time everything just right.
• Govt combined economy - pretty much twice what everything else has!

Bob Wilson

 

In their testing, they found it would not charge at 7.5 kWh so they are replacing the power electronics module (aka., Prius inverter.) Should be ready Monday. <SIGH>

Bob Wilson