[75fusca]

Originally Posted by abbike18

Yeah there are. I still need to figure out how I'm going to strap it down. I'll try to update once I do.

Perhaps you could explore attaching these type of short straps to some of those exposed bolts that go into the body, and then some regular strap looping through them?

These types come with metal rings at the ends to firmly secure to the body bolts.

[TomCanada]

What's the downside of just carrying a can of "Fix a Flat"? I used to do that in my 335i, and really don't want to bother with an actual spare. Between roadside assistance and the fix-a-flat, I should be covered, no?

[lap777]

Originally Posted by TomCanada

What's the downside of just carrying a can of "Fix a Flat"? I used to do that in my 335i, and really don't want to bother with an actual spare. Between roadside assistance and the fix-a-flat, I should be covered, no?

Depends on your circumstances. Some flats are more than a hole, and roadside assistance might not work for remote areas (no cell service for example) or just take too long.

[abbike18]

Originally Posted by TomCanada

What's the downside of just carrying a can of "Fix a Flat"? I used to do that in my 335i, and really don't want to bother with an actual spare. Between roadside assistance and the fix-a-flat, I should be covered, no?

Totally agree with you for everyone who stays within cell service, etc. I'm in CO and had a run flat go flat on me during a camping trip. Driving down a dirt twisty road with a flat runlet was just horrible for me, and its common to not have cell service. So that's my personal reason for going this route.

[jsh139]

Originally Posted by TomCanada

What's the downside of just carrying a can of "Fix a Flat"? I used to do that in my 335i, and really don't want to bother with an actual spare. Between roadside assistance and the fix-a-flat, I should be covered, no?

If the tire isn't destroyed and could perhaps be repaired, some tire shops will refuse to repair it if you used fix-a-flat. Just something to keep in mind.

[lap777]

Originally Posted by jsh139

If the tire isn't destroyed and could perhaps be repaired, some tire shops will refuse to repair it if you used fix-a-flat. Just something to keep in mind.

True, and there's the potential of damaging the pressure sensor.
And riding a flat run-flat will also destroy it.

I have run flats, so my plan starts with a compressor: if I can get to a tire shop by just adding air, I'll do that. Plan B is to attempt to plug it. Plan C is to fix-a-flat. Plan D is to run on flat. Plan E is roadside assist. But I'm fully aware I'm not prepared for plan F, changing the tire. I plan travel accordingly.

[abbike18]

Quick update - created a strap down system. There are 4 mount points in the ratchet strap webbing. The two upper ones are the ends of the ratchet strap, and are simply the holes in the trunk floor. For the lower mounts there are two threaded holes in the trunk floor - they are M10*1.5 thread. I got two bolts and then fabbed the mounts with some steel stock and two d-rings. The rest is pretty self explanatory from the picts!

[75fusca]

Excellent, well done!
Thank you for sharing your install

[X3rd Time Is a Charm]

I personally couldn’t take the ride of the run flats . Being our 3rd X3 and never having run flats , I recently changed to Non run flats . Being just my Wife and myself losing the cargo room wasn’t a big deal . So I just bought the Modern Spare full kit and keep it in the boot tied down with a strap to the welded anchor points provided in the boot . The superior ride comfort, handling and less noise of the Non run flats , I felt it was well worth the loss of the room in the boot .

[Drexel_Lake]

Originally Posted by X3RD TIMES A CHARM

I personally couldn’t take the ride of the run flats . Being our 3rd X3 and never having run flats , I recently changed to Non run flats . Being just my Wife and myself losing the cargo room wasn’t a big deal . So I just bought the Modern Spare full kit and keep it in the boot tied down with straps to the supplied adjustable deck supports . The superior ride comfort, handling and less noise of the Non run flats , I felt it was well worth the loss of the room in the boot .

Pics or it didn't happen.

[br438]

FYI: On the Audi Q5 "expanding" spare. Both the X3 and the Q5 have a 5x112 bolt pattern, correct?

We need someone to confirm that the audi spare could be safely fit (and run) on an X3. That would be a game-changer for this spare retrofit game.

caveats:
1) I am having a difficult time imagining the Audi spare wheel clearing the M Sport Calipers/Disc.
2) In the video linked earlier, it did take 11 minutes just to inflate the Audi spare -- possibly not much different than re-inflating the BMW spare that we have to air down.

[X3rd Time Is a Charm]

Originally Posted by Drexel_Lake

Pics or it didn't happen.

I can’t get the app to accept attachments .It’s just a spare tire in a case sitting in the back of the car . Cost around $490.00 US Dollars . It’s a 18” wheel with a conti temporary tire on it . Measure’s 28.5” overall , so it won’t fit under the lid .

[stoked335d]

Interesting thread. Well done hack if you have RFT tires and want switch to nonRFTs. This car should have been designed better in regards to spare tire. My 1994 300zx had an OEM, inflated small spare that worked out well. 335d came with RFTs and resourced my own spare from a 5 series similar to OP did. There was no space under the trunk and it took some space inside instead. It was worth it cause it became a totaly different car on Michelin PS2s at the time. Was reading this thread to see if I can get the mobility kit version on my on order X3MC but don't think 19" spare will fit. Getting the default hump trunk version instead.

[abbike18]

Originally Posted by stoked335d

Interesting thread. Well done hack if you have RFT tires and want switch to nonRFTs. This car should have been designed better in regards to spare tire. My 1994 300zx had an OEM, inflated small spare that worked out well. 335d came with RFTs and resourced my own spare from a 5 series similar to OP did. There was no space under the trunk and it took some space inside instead. It was worth it cause it became a totaly different car on Michelin PS2s at the time. Was reading this thread to see if I can get the mobility kit version on my on order X3MC but don't think 19" spare will fit. Getting the default hump trunk version instead.

I agree the car should have been designed better. After doing a spare retrofit solution, its clear that a few modifications could allow the spare to fit (while fully inflated) under the standard trunk. I'd really like to talk to a BMW engineer who knows why they didn't design it this way.

[Flippco]

Originally Posted by abbike18

Quick update - created a strap down system. There are 4 mount points in the ratchet strap webbing. The two upper ones are the ends of the ratchet strap, and are simply the holes in the trunk floor. For the lower mounts there are two threaded holes in the trunk floor - they are M10*1.5 thread. I got two bolts and then fabbed the mounts with some steel stock and two d-rings. The rest is pretty self explanatory from the picts!

This looks like a great solution! I'm considering ordering without the spare tire and then doing this when ditching the run-flats. Any long-term updates? Is this still holding up well?

[abbike18]

Originally Posted by Flippco

This looks like a great solution! I'm considering ordering without the spare tire and then doing this when ditching the run-flats. Any long-term updates? Is this still holding up well?

Yep, still holding up well. Honestly don't notice it. Every time I've checked on it everything is fine.

[Flippco]

Originally Posted by abbike18

Yep, still holding up well. Honestly don't notice it. Every time I've checked on it everything is fine.

Awesome, thanks for the update! I'm going to do that. Thanks for all the information!!!!!

[Flippco]

Originally Posted by abbike18

Yep, still holding up well. Honestly don't notice it. Every time I've checked on it everything is fine.

Do you know the approximate total diameter of the BMW spare? I'm wondering if I'd be able to order the modern spare and squeeze it in. I believe the modern spare is 28 1/2". It does say on their site it won't fit in the cavity but I wonder if I let some air out if it will fit.

[abbike18]

Originally Posted by Flippco

Do you know the approximate total diameter of the BMW spare? I'm wondering if I'd be able to order the modern spare and squeeze it in. I believe the modern spare is 28 1/2". It does say on their site it won't fit in the cavity but I wonder if I let some air out if it will fit.

I can go measure it...but you can also use the tire size to figure it out.

The BMW tire is 135-80-R18. So the rim is 18" in diameter. The tire has a 135mm tread width, and the sidewall is 80% of that, which means it has a 108mm sidewall = 4.25". Times 2 plus the rim and you get 26.5" for the BMW solution.

Based on my experience fitting the BMW tire in there you would have trouble with the modern spare.

I got my tire from bimmerzone

[Glock20C]

Originally Posted by abbike18

Quick update - created a strap down system. There are 4 mount points in the ratchet strap webbing. The two upper ones are the ends of the ratchet strap, and are simply the holes in the trunk floor. For the lower mounts there are two threaded holes in the trunk floor - they are M10*1.5 thread. I got two bolts and then fabbed the mounts with some steel stock and two d-rings. The rest is pretty self explanatory from the picts!

Just wondering, can that grey like foam on the upper part of the well be removed so the tire does not have to be deflated? I'm a little weary with the tire hitting on the negative battery terminal.

[abbike18]

Originally Posted by Glock20C

Just wondering, can that grey like foam on the upper part of the well be removed so the tire does not have to be deflated? I'm a little weary with the tire hitting on the negative battery terminal.

There's a little bit of foam, but then it's metal from the body. So I don't think so.

Also, the tire is hitting the battery mounting bracket. This bracket is extremely sturdy, so I'm not concerned about it.

[njw1967]

Hi guys
Does anyone have the part number for the spare wheel?

Also what size is it and will it fit with 21" and large M callipers?

Thanks NJW