300 miles trip with Rex, exerpience and points to make

[old4d]

Oh Well, I had to admit I did not do this on purpose, I originally planed to use my wife's car to go on this trip, while forgot this, and leave me no option but driving this 300 miles round trip with my I3 Rex.

Weather is pretty nice that day, 75 degree in November is not normal but good to make this trip. Finished the trip with 3 stops to the gas station, spend $4.00, $5.50 and $5.00 each top-off, well, you do not want to see the gas station cashier's face though, when I said filled up and only paid 4 bucks.

a few points:
1) NAV will point you to the route not using High way, be aware of this, you have to manually turn on this prefer highway, or you would end up like me driving country road for more than two hours! Or, simply use your Google Map.
2) 75 Miles can be done with battery but it drains it pretty fast, also it is really not stable for REX option, as I see the 6% bar is shrinking when Rex is running and I am on cruise control and climbing a very small hill.
3) The mileage indicator is a Joke or it is a wide guess depending on your NAV route option, I filled up the tank, and it gives me 55 miles , 62 miles and 75 Miles respectively, and if you stop and restart the engine, well, it changes again and mileage did reduced.
4) I do see the i3 is most efficient in both REX or EV mode if you are driving average 55-62 miles, stop and go traffic actually helps, other words, no more than 100km/hr.
5) I do see the manual REX option is a must-have for this car, since when you are driving, if you could have a 75% battery left, you can use the gas up to the last drop, I mean giving it just a couple of miles left before you switch back, so you can really top off it to the maximum tank capacity while have enough safety reserve, more efficient for long miles trip. If not, believe me, you will be surprised how many gas stations showing up, because now you are constantly searching for them!

I made my trip, and a couple of coffee break did not bother me at all, knowing the REX is capable of doing long trip is a great comfort and peace of mind to me, I will not be surprised to see people doing even crazier long trip with it, or climb the Mountain Washington with it.

People, really, show off when you are on top of the Mountain Washington with this car, mod your car first through to turn on the REX before you climb though, as I really don't think it can do it alone with only a full battery. :mrgreen:

 

[FrancisJeffries]

In the UK, I have the benefit of being able to switch the Rex on (and off!) whenever the battery is at or below 75%. My long-range (and the longest so far is 700 miles!) modus operandi is now to switch the Rex on ASAP after 75% battery is achieved. Then run until it's empty (or almost empty) and drive to the next service station on battery and refill. On motorways that seems to be every 90-95 miles at 70-75mph.
Remember to switch the Rex back on again as soon as you leave the service station!

On a 700-mile round trip I never recharged the battery at all, and never had any range anxiety. In fact, on the way home, I deliberately switched off the Rex so I could find out what happened when it got to the USA 6% mark: it simply switched the Rex back on and I'd used as little petrol as possible. I feel really sorry for our American colleagues, because they have bigger hills than we do in the UK, so the lack of Rex control can really hurt the i3's attractiveness.

Using the car this way doesn't please the purists but it avoids me having to have a second, ICE, car just for longer journeys, and I can enjoy the i3 all the time.

 

[old4d]

In the UK, I have the benefit of being able to switch the Rex on (and off!) whenever the battery is at or below 75%. My long-range (and the longest so far is 700 miles!) modus operandi is now to switch the Rex on ASAP after 75% battery is achieved. Then run until it's empty (or almost empty) and drive to the next service station on battery and refill. On motorways that seems to be every 90-95 miles at 70-75mph.
Remember to switch the Rex back on again as soon as you leave the service station!

On a 700-mile round trip I never recharged the battery at all, and never had any range anxiety. In fact, on the way home, I deliberately switched off the Rex so I could find out what happened when it got to the USA 6% mark: it simply switched the Rex back on and I'd used as little petrol as possible. I feel really sorry for our American colleagues, because they have bigger hills than we do in the UK, so the lack of Rex control can really hurt the i3's attractiveness.

Using the car this way doesn't please the purists but it avoids me having to have a second, ICE, car just for longer journeys, and I can enjoy the i3 all the time.

Not only that, we had a smaller tank at tiny 1.9 Gallon Tank, versus 2.4 Gallon. It is not bothering me at least for now, but the sales is going to be hurt big times without this feature.

 

[paule23]

Is there any particular reason why UK owners have the option to turn the REX on or off, and US owners do not? Seems very strange to me.....

 

[mindmachine]

Is there any particular reason why UK owners have the option to turn the REX on or off, and US owners do not? Seems very strange to me.....

In order to get carbon credits that enable BMW to sell gas guzzlers in California they sought a special designation of BEVx, which is electric vehicle extended range which has limitations on how the car is allowed to perform. This gives BMW the maximum amount of credits per car sold.

The Law is called CARB and under this regulation if the Rex was supplied as it works in other parts of the world the i3 would have to have been rated as PHEV, or plug in hybrid and BMW would not have been eligible for as many credits per i3 sold in the state and thus would have had a higher CARB tax on each gas guzzler it sold in the state of California. There are 15 CARB states in the US and some of the other states offer tax rebates to buyers of EV's so they benefit too. But the customers in the other 35 states are stuck with an inferior arrangement.

So those of us who bought the Rex are penalized and left with an inferior arrangement, plus we are subsidizing people who buy BMW gas hogs.

 

[paule23]

I've heard of CARB I just didn't realise that was the reason. There's an interesting graphic in Scientific American this month about top manufacturers and whether they have hit their CAFE targets (Corporate Average Fuel Economy). BMW have only just started hitting their target (now 1.6mpg above), it seems the Japanese manufacturers do best (the targets are flexed for the companies particular mix of car types).

Porsche are the worst large manufacturer 5.1mpg below their target.

 

[TomMoloughney]

I just took a 462 mile round trip form NJ to Vermont last weekend. Roughly 300 miles on REx and about 112 on battery. All done with temperatures in the low teens to the mid 20's and most of the Vermont driving was on snow covered roads. Lots of hill climbing but as long as I kept an eye on the SOC there was no issue. Set the ACC to 70 mph for the highway driving and we did the whole trip without and reduced power issues. I'll have a full blog post out on the trip soon.

 

[JNS]

I've had an i3 for about two months. Just used REx for first time (other than two maintenance cycles the car automatically ran). It was very noisy -- even when the car was stopped. Not quite as loud as a lawnmower, but close. From the posts of other owners, I was expecting it to be fairly quiet -- especially with the engine running at the lowest speed.

Is your REx noisy as well, or is it possible something is wrong with my engine? Without cranking up the stereo, it would've been very annoying to take a long trip using REx with that much engine noise.

 

[PhilH]

Running at 58 mph, our REx is pretty much inaudible. In town, running very slowly, you just about know it's there, but you have to listen out for it to hear it.

 

[mindmachine]

I've had an i3 for about two months. Just used REx for first time (other than two maintenance cycles the car automatically ran). It was very noisy -- even when the car was stopped. Not quite as loud as a lawnmower, but close. From the posts of other owners, I was expecting it to be fairly quiet -- especially with the engine running at the lowest speed.

Is your REx noisy as well, or is it possible something is wrong with my engine? Without cranking up the stereo, it would've been very annoying to take a long trip using REx with that much engine noise.

My has only run the maintenance cycle once and it was in town at about 25 to 35mph with a stop or two for traffic lights and I could barely hear it. I mostly just noticed the slight vibration.

 

[old4d]

I've had an i3 for about two months. Just used REx for first time (other than two maintenance cycles the car automatically ran). It was very noisy -- even when the car was stopped. Not quite as loud as a lawnmower, but close. From the posts of other owners, I was expecting it to be fairly quiet -- especially with the engine running at the lowest speed.

Is your REx noisy as well, or is it possible something is wrong with my engine? Without cranking up the stereo, it would've been very annoying to take a long trip using REx with that much engine noise.

You may need to check with your dealer, as said by other owner, sometime, with radio on, I have to turn on the NAV system screen to check if it is running if I am below 60m/hr, running on 75m/hr on highway you can hear the low humming sound if turn radio off, but not that loud as my lawnmower.

 

[WoodlandHills]

The tire noise will drown out the REx noise at speeds over 40mph and you won't hear it until you slow down again. It is kinda loud when going slowly or when stopped, perhaps this is why the REx shuts off at stoplights?

 

[old4d]

I just took a 462 mile round trip form NJ to Vermont last weekend. Roughly 300 miles on REx and about 112 on battery. All done with temperatures in the low teens to the mid 20's and most of the Vermont driving was on snow covered roads. Lots of hill climbing but as long as I kept an eye on the SOC there was no issue. Set the ACC to 70 mph for the highway driving and we did the whole trip without and reduced power issues. I'll have a full blog post out on the trip soon.

Way to Go, Tom, your blog inspired me or "tricked" may others into buying and owning I3, very thankful for your constant input on your experience, can not wait!

My wife got chance for last storm we had in Northern NJ to try out our all 19's season tires, it works just fine, better than I expected, but I assume that all your 20's summer tires, you are really brave doing that though, my brother used to own a 745 with summer tires, and he have to back into his entire drive way which had very little grade difference in winter time, because heads on, the 745 with summer tires did NOT move at all. :mrgreen:

 

[old4d]

The tire noise will drown out the REx noise at speeds over 40mph and you won't hear it until you slow down again. It is kinda loud when going slowly or when stopped, perhaps this is why the REx shuts off at stoplights?

I think this very subjective topic, it really depends, I get my loaner of 328i for quite some times now and I really miss my quiet cabin of I3, even when the Rex is running.

The other thing I noticed is there is a fix period of time, I think, called warm up time, which the Rex will keep running for certain time even you stopped, One day, I was 1.5 miles into the Rex, and park and turn off the car, and it is still running and it is very loud if you step outside and hear it, I think this could be fans or something to cool it off, just like some of the old Projectors.

 

[user 1096]

Old and Tom, Many thanks for these reassuring notes. I have periodic sport weekend destinations (shooting and boating) that are about 70 miles away and over hilly terrain. I have been using my old 545 for them, but wanted to hear how repeated gasoline refills affected performance.

My VT trips to Manchester have been supplemented by the friendly Chevy Volt dealer there (on weekdays), but I always wind up on Rex gas on the way home, but never have refilled and continued driving. I'll tackle this tactic now.

I did notice that the BMW nav will direct me OFF high-ridge highways/interstates and onto valley local roads when elevation is a serious consideration (US 7 north of Bennington nav pointed me to valley route Historic 7A). I also find much better mileage on interstates running below 60. Keeping it pegged at 70 seems to drain the juice faster even on cruise. But stop-and-go local roads seem to sip power best; being retired now, maybe I should start taking what I consider as motorcycle cruise routes!

 

[jadnashuanh]

For those that haven't played with the nav system much, it gives you several choices about the route to minimize energy use or time, and if you aren't likely to make it without a recharge or refueling, it guides you to those locations as well. Now, if we ever get some CCS units around here, I might venture further, but don't need to often, and my other car does need the cobwebs brushed off once in awhile, too!

 

[TomMoloughney]

BUMWA: I drove from New Jersey to Manchester, VT so for you to go there from Albany is a piece of cake! I had already driven over 150 miles before I reached Albany!

old4d: I bought a set of after market wheels and Blizzak winter tires. The 20's are summer tires and they really are not meant for winter driving. Your 19" tires are All Seasons so you should be OK. I did a post about the winter wheel/tire set that I bought:
http://bmwi3.blogspot.com/2014/11/bmw-i3-tires-get-ready-for-winter.html

 

[hrmandell]

The Rex operates on 3 speeds, with the max speed being similar to a quiet lawnmower. You don't hear it much at highway speed.

On the CARB limitation, how long do you think there will be an aftermarket upgrade to allow the Rex to engage at will? I don't see it failing smog tests in CA if it did that, though one could say it is cheating.

 

[mindmachine]

The Rex operates on 3 speeds, with the max speed being similar to a quiet lawnmower. You don't hear it much at highway speed.

On the CARB limitation, how long do you think there will be an aftermarket upgrade to allow the Rex to engage at will? I don't see it failing smog tests in CA if it did that, though one could say it is cheating.

Read the coding section thread on this blog, it is already available you just have to change the setting by recoding the software switch. If you want to do it yourself there are instructions on the BMW facebook group. If you don't want to do it yourself just find someone who does BMW aftermarket coding. Just remember however that any software updates will probably reset the code and you will have to do it again.

Several have reported already that they did it to their cars, and it is not that hard to do.

 

[Ruffles]

Like a few others have mentioned, the REX can run at various speeds depending on need. When I was making my 280 mile trip home with the car, I used Rex several times. The first time it came on, it was very quiet and I had to turn the radio off and listen to see if it was really going. As we neared home, the outside temp was below 0F. REX was really screaming at this point and didn't turn off at stoplights etc. Since that trip, the few times I've used it its been very quite.