Any real limit to running REX?

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Just of interest what is im3 rex runtime readings all of your i3 rex's? We have a 2016 with 104K Km (65K Mi) on the clock and the rex has done 11k km (6.8k mi) on the clock. does BMW have a basic expected runtime on the rex? What's the highest anyone has reported on their Rex?
 
I've driven for 600+ miles in one day with 550 miles of it on the rex, I added an extra fuel tank so my rex range is roughly 250 miles.

I did need to stop for gas, but other than that it's gone just fine. It keeps up pretty well as long as you're not going 70+ the entire time. I would turn it on at 75% and leave it until I was within 50 miles of home and use the battery for the last bit of my trip.

You can drive on the rex so long as you have fuel.
Can you give us details on your extra fuel tank?
 
Can you give us details on your extra fuel tank?
People install tanks in the frunk. Done right, they don't throw codes but require some pretty sophisticated mods with proper venting, pumps, hose etc. There's also a contingent that just puts a fuel can in the frunk.

That said, you will get a huge reaction from posters here. Most say "frunk is a crumple zone, you are asking for a fire" and other say, "nah, no problem." I'm in the "not worth the risk" category.

This dude showed that if the gas station is on the exit ramp (or you hit a green light), from leaving highway to re-entering highway after fill-up is two minutes. And he wasn't trying for a NASCAR or Formula One stop, he just kinda sauntered.
 
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People install tanks them in the frunk. Done right, they don't throw codes but require some pretty sophisticated mods with proper venting, pumps, hose etc. There's also a contingent that just puts a fuel can in the frunk.

That said, you will get a huge reaction from posters here. Most say "frunk is not a crumple zone, you are asking for a fire" and other say, "nah, no problem." I'm in the "not worth the risk" category.

This dude showed that if the gas station is on the exit ramp (or you hit a green light), from leaving highway to re-entering highway after fill-up is two minutes. And he wasn't trying for a NASCAR or Formula One stop, he just kinda sauntered.

". . . PLEASE PREPAY BEFORE PUMPING" . . . nice . . .
 
Because of the way that the REx is decoupled from the wheels, it seems unlikely that its total use could be expressed in miles. There are situations where the petrol engine contributes only part of the energy while driving (i.e. the battery is still discharging, even with input from the REx) and there will be others where it contributes more.

So I suspect that the best you could hope for is the total runtime of the engine. In theory the total number of revolutions could be logged, but I doubt they bother.

If the rest of the "driver experience" is anything to go by, it's unlikely that BMW would have made this data visible to the owner anywhere, so you would probably need a diagnostic tool such as BimmerLink to access the data, if it's available at all.
They should show " runtime" of the engine, like a commercial tractor. ( I think you can show it on a obd reader)
 
The REX and its fuel system didn't like it. When i switched to Shell ethanol-free fuel, I didn't have a problem from this moment. Now it is no more available since a few months,
You can go to a small airport and buy 100ll (low lead) they don't allow corn lcker in aviation fuel yet. Good stuff for small engines that sit a lot like lawnmowers in the great white North ❄️
 
It is, but in a car with efi it’ll absolutely still have the sensors, and I’m sure the emissions control equipment too.
 
The Rex should have a lot of longevity. It's a robust scooter engine and in the I3 it's really not connected to the drive train but only acts as a generator.
 
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