Full size spare will fit in ND boot

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91mx5
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Full size spare will fit in ND boot

Postby 91mx5 » Thu Nov 22, 2018 3:43 pm

After searching for a space saver spare for my ND to no avail, I decided to make up a full size wheel & tyre to keep at home. Inconvenient, but at least I had access to a wheel if needed. Then I studied the boot and found that if I removed the front and rear boot lining panels, and removed 3 x bolts to enable removal of the lock mechanism, the full size wheel will just fit in the boot. It is necessary to disconnect 2 x electrical connections to the lock mechanism, then swing it out of the way. Wrap it in a rag so as not to scratch the paint. (Draw around the lock mechanism with Nikko pen first to make refitting easier). I also deflated the tyre to make it a bit more pliable, but every ND has a compressor, so it's easy to reinflate when needed.
I live in a country town and often drive on pretty ordinary road surfaces where a blown tyre would be very possible and often there is no mobile phone coverage in these areas. I feel much happier now knowing that I won't be stranded with a simple flat tyre, and also, now that I carry a spare, I am confident that I'll never have a flat!! I bought a new CSA "Essen" wheel and cheap new "HIFLY" tyre with exactly same specs as standard wheels. Cost $374 altogether, but would be cheaper in major centres as I had to pay freight too. Hope this is of interest to other concerned ND country travellers.

ps. DO NOT CLOSE BOOT LID BEFORE RECONNECTING ELECTRICAL LEADS TO LOCK MECHANISM. If you do, electrical unlock won't work and you will have to revert to mechanical cable pull behind drivers seat, very akward (Don't ask me how I know...)
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bruce
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Re: Full size spare will fit in ND boot

Postby bruce » Thu Nov 22, 2018 8:14 pm

A $20 can of tyre foam would have solved your problem.
I have never heard of a new, good quality, aired-up tyre 'blowing out'. If that happened I'd be more concerned about the tree I was about to run into!

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charcoal
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Re: Full size spare will fit in ND boot

Postby charcoal » Fri Nov 23, 2018 8:37 am

Well done!

Your situation (Stanthorpe) is understood and the chances of having a sidewall damaged rendering the tyre u/s means that you really have taken the bull by the horns to come up with a satisfactory solution - I applaud your determination and persistence :D

The bonus from your exercise is that in the event of having a puncture, now the removed wheel can be placed back into the boot.

I imagine that other ND owners may now re-think their spare wheel situation thanks to your initiative.

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Re: Full size spare will fit in ND boot

Postby project.r.racing » Mon Nov 26, 2018 9:39 am

Surprizing you couldn't find a space saver. Any corolla or fwd kia/hyundai shouldn't had something that would've worked.

At least your way, you dont have to limp the car home if you have a flat.

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Re: Full size spare will fit in ND boot

Postby greenMachine » Mon Nov 26, 2018 1:43 pm

bruce wrote:A $20 can of tyre foam would have solved your problem.
I have never heard of a new, good quality, aired-up tyre 'blowing out'. ...


Nope. We had an ND stake a tyre on a run a few months back, no way would gunk fix it (ie tried and failed). Another car took him the 1.5hr drive home to pick up spare, and 1.5hr drive back. They were luck they were in company, and while highly inconvenient, the logistics allowed someone to bail them out.

The can of foam would only be useful in very limited circumstances.

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bruce
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Re: Full size spare will fit in ND boot

Postby bruce » Mon Nov 26, 2018 3:14 pm

You guys are amazingly unlucky. In my 30+ years of driving the only punctures I've had were the slow deflation due to a typical nail/screw (and then only a handful of occurrences).
As said, a space saver would be the next option.

91mx5
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Re: Full size spare will fit in ND boot

Postby 91mx5 » Mon Nov 26, 2018 8:45 pm

Of course it's up to every individual to decide how they want to deal with a potential flat. My post was just there to let others know that it is just possible to take a full size spare in an ND boot, which is my choice in my environment. Any old 4 x bolt space saver will not necessarily fit over the brake calipers on an ND GT with 17" wheels and bigger brakes, but I'm sure there must be something out there which is suitable. However, my enquiries at a Mazda service department advised not to fit a wheel of smaller diameter to either front or rear axles. If fitted on rear axle with a limited slip diff, it may damage the diff if dríven too far, don't know how far is too far though. If fitted on front axle, different rotation speed of front wheels will upset ABS braking and Stability control. Also, they claim braking may be unstable in an emergency with different width tyres on the front.

If you find a skinny space saver with the same diameter as the road wheels, then you have the same problem fitting it into the boot as a road wheel because the distance between the front and back of the boot is too small when the original boot linings remain in place.

These potential issues may or may not be true, I don't know, but replacing a wheel with another of the same specifications removes any of these problems, and will allow me continue on my journey at full legal speed.

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Re: Full size spare will fit in ND boot

Postby 93_Clubman » Tue Nov 27, 2018 9:25 am

The lack of a spare of any kind or the supply of a space saver certainly polarises, so it's useful to hear how forumites go about solving issues facing them. No doubt there will be other ND owners interested in your approach.

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charcoal
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Re: Full size spare will fit in ND boot

Postby charcoal » Tue Nov 27, 2018 9:59 am

I continue to applaud this member for his well-researched and informative article.
His particular circumstances indicate that he has made a wise decision to carry a full-sized spare wheel/tyre combination in his ND.

I have heard of a number of MX5 owners who have had issues with tyre sidewalls which are fubar just from driving on suburban roads, plus a recent case where friends with an NC have ended up replacing four 17" wheels as they were unable to source an OE rim (one of theirs was badly buckled) within a reasonable time...and needed to have the car available for use as a daily drive. Greenmachine's post was also relevant with regard to the usability of the $20 can of tyre foam.

Although we rely on the originally supplied spacesaver for our NB most of the time, I sourced a full size wheel/tyre early in our ownership for those occasions where we anticipate driving on "problem" roads a long way from home. I would be concerned if we decided to replace the NB with one of the newer series cars. I was unaware of the issues raised by 91mx5 in his post with relation to using a spacesaver on front or rear where the car has limited slip differential fitted, plus the ABS and stability control issues outlined.

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hks_kansei
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Re: Full size spare will fit in ND boot

Postby hks_kansei » Tue Nov 27, 2018 10:41 am

It's worth noting that my understanding is that the stability control issue is more if the space saver is substantially smaller in Diameter than the rest, rather than width. (and LSD is the same, since the diff diameter would mean the LSD trying to constantly slow down the one wheel that is spinning faster, well depending on LSD type)

I can only assume that the different rolling speed from a smaller/larger wheel would trick the computer into thinking that wheel is spinning and would try to apply the brake to stop it.


Space savers are a far better option than a can of goo, which apart from sometimes not working, also means that what may have been a $20 puncture repair at the next town becomes a $150 replacement tyre.

In saying that, a space saver is kind of like a peg leg.
it gets you walking again, but you'll have a heavy limp, and it's not as good as the original leg.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Re: Full size spare will fit in ND boot

Postby project.r.racing » Fri Nov 30, 2018 1:42 pm

Even a full size spare tyre (same size as normal running tyre) but a different make and model will throw off the stability control. As the frictional rating can be completely different.

If one was serious about issues with stability control, they would be buying a wheel and tyre package not matching the weight and frictional ratings of the main for tyres.

The LSD concern is a ligit concern. And any car brought in the user manual has warnings about this. It is fairly common knowledge. But most user manuals go like this, "only use space saver on front wheels etc / only use space saver on back wheels etc". Geez even a tyre with 5psi less than the other will throw off the LSD.


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