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Qube
12-29-2007, 01:47 PM
Was going to take the spare out of the e39 and toss things in like detailing towels/sprays, booster pack, mini compressor, etc. Should add up close in weight but not quite. Was also told the wheel is structural in not allowing the rear to crumple like a can in collision (aside from possible balance weight issues). Thoughts?

vince
12-29-2007, 02:22 PM
Seems like it is indeed meant to resist crumpling. I have a '94 525iT that was rear ended hard, and the spare tire did do quite a bit to lessen the amount of crumpling of the trunk floor.

vince

infurno
12-29-2007, 02:36 PM
I thought crumpling was a good thing? Absorbs the energy from the impact so it does not kill you.

vince
12-29-2007, 02:42 PM
Yep, but it acts like an airbag of sorts, absorbs impact and also prevents excessive crumpling of the trunk floor/gas tank

rob101
12-29-2007, 02:52 PM
isn't the purpose of the boot to crumple in the event of an accident, in order to absorb the kinetic energy of the impact. the passenger cabin is meant to be Rigid and impenetrable.

Its an interesting point though, as the spare wheel isn't strong like an engine it would likely contribute to the energy absorption during a crash by crumpling.

Barney Paull-Edwards
12-30-2007, 12:58 AM
My polish neighbour has a `98 525 which was hit hard on right rear, the wheel well took most of the force,wheel had to be cut out but car pulled out easy and apart from battery crush damage to wiring, came out fine.That wheel does a lot more than sit there so I would stronly suggest leaving it in!

Qube
12-30-2007, 04:38 AM
Ok, sounds good. Perhaps I'll install it 'upside down' so I can store inside it :)

filip00
12-30-2007, 12:31 PM
i think it is really an issue you could call.....IRRELEVANT. ;)

94_e34_525i
12-31-2007, 12:15 PM
Is it really necessary to point out your neighbor is polish? lol

CharlesAFerg
12-31-2007, 12:28 PM
My mexican neighbor has an e36. :D
Surprise!

If it's so important structurally and you don't want the weight, why not put something else in there that would be most effective at crumpling but not weigh much...?

Sam-Son
12-31-2007, 04:23 PM
i think it is really an issue you could call.....IRRELEVANT. ;)
Yeah I think the spare wheel will be the least of my worries in an accident besides if my car is rearended hard enough that the trunk caves in then the spare won't be enough of a help.

repenttokyo
01-02-2008, 01:57 AM
here's the question no one has asked yet: why are you removing the spare tire from your daily driver? Are you using run flats or solid steel tires?

philbyil
01-02-2008, 02:09 AM
The placement of the spare wheel is part of the structural design element in the event of a rear end crash.

Sam-Son
01-02-2008, 07:07 AM
here's the question no one has asked yet: why are you removing the spare tire from your daily driver? Are you using run flats or solid steel tires?
Im assuming its for weight saving measures...at least thats why I would do it

repenttokyo
01-02-2008, 07:24 AM
Im assuming its for weight saving measures...at least thats why I would do it


weight in a daily driver ? qube, what are you going to do if you get a flat?

Qube
01-02-2008, 07:33 AM
weight in a daily driver ? qube, what are you going to do if you get a flat?

No, not weight. As it stands now, the sub and other goodies take up trunk space. EG: battery booster, few towels, etc.

The motivator is that I can no longer transport even a simple 1U server in the back. If I can move everything other than the sub into the spare wheel well, it will fit fine.

If I get a flat, I can either use the fix-a-flat I keep... plus the booster/inverter/inflater pack. Else, call roadside as I have two years of that which came with the purchase.

That's the motivator there.

NB: in the e34, I didn't mind transporting them on the rear seat with a few towels but not in this baby :)

Sam-Son
01-03-2008, 01:50 AM
weight in a daily driver ? qube, what are you going to do if you get a flat?
I dunno Some people are nutty like that and want as much performance as possible...I'm one of the those people but I'd still leave the spare in
Even if I got a flat and pulled off to the side of the road I wouldn't be able to change the wheel because of the crappy tools BMW gave us

repenttokyo
01-03-2008, 03:18 AM
I dunno Some people are nutty like that and want as much performance as possible...I'm one of the those people but I'd still leave the spare in
Even if I got a flat and pulled off to the side of the road I wouldn't be able to change the wheel because of the crappy tools BMW gave us

the bmw wheel tools are indeed crappy, I replaced them with ones that actually work. I remove my tire at the track, but I don't take my BMW to the track.