tyres question

Technical questions and answers about the Mazda Bongo

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bobby_badger
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tyres question

Post by bobby_badger » Sun Jun 19, 2022 2:32 pm

Hi all

In preparation for a forthcoming trip away in our 97 4x4 2.5L diesel Bongo I decided to check the spare wheel. The tyre itself looked in pretty good nick but thinking it wasn't fully inflated we took it to a garage and sure enough it was only 11psi. During inflation, after a certain point I could hear air coming from the valve so that's knackered - perhaps just the valve can be replaced. The four tyres on the vehicle currently are 215/65R15 but the spare is 215/70R15 C 106/104S (not sure what the C refers to).

I have read various posts and the fact sheet about having four identical tyres rather than the different ones front and back which Mazda recommend and I'm happy that a) the current setup is okay and b) most other people do this without issue. That brings to my questions;
  • Does 215/65R15 seem like a good choice for all four tyres? The tyre information plate on the doorwell says rears should be 215/70R15 - I would be better to have 215/70R15 on all four presumably?
  • Assuming we are sticking with our existing 215/65R15s, if we could just replace the valve on the spare tyre would it be safe to use it as a spare even though it is 215/70R15? Presumably once the punctured tyre is replaced we should swap back rather than use the differently specced spare longer term? Might be easier just to get a new spare at 215/65R15 which means if we have a puncture we could fit the spare on the vehicle permanently and put the repaired or replaced tyre back as the spare.
Thanks for any input.

Iain
Bob
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Re: tyres question

Post by Bob » Sun Jun 19, 2022 7:38 pm

Hi

A quick Google of 'tyre size calculator' shows your tyres have a circumference of 81.7” and the spare 84.3”.

Personally with a 4wd I wouldn't chance it as you could cobble the transmission for the price of a tyre.

Pretty sure the 'C' means it’s a commercial, or van, tyre rather than a car tyre. More robust, harsher ride, but I stand to be corrected on that.

Important to note the minimum load ratings, 92 front, 96 rear. A higher number is fine.

Also worth checking the date of manufacture, 4 digit code giving week number and year the tyre was made. If more than 7 years I'd replace it, particularly the spare. There's a lubricant in the compound which can only work when the tyre rolls, which is why caravan tyres perish young.

Hope that helps. 8)
bobby_badger
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Re: tyres question

Post by bobby_badger » Sun Jun 19, 2022 8:10 pm

Hi Bob

Thanks for your reply. I did read that the date of manufacture was on the inside of the tire! But I will try and check them.

You're saying not to risk using the spare as it stands (wrong size). Any thoughts about using 215/65R15 on all wheels when the rears should be 215/70R15? Not sure how much difference the aspect ratio of the tyre makes.

The van is always rammed so any tyre I replace will have a load rating of 96 or ideally higher.

Iain
Bob
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Re: tyres question

Post by Bob » Sun Jun 19, 2022 8:59 pm

As long as they are the same I can’t see 215/65s hurting, but don’t take that as legal advice. :wink:

Edit: Date code looks like this:

https://www.gov.uk/government/publicati ... -minibuses
bobby_badger
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Re: tyres question

Post by bobby_badger » Sun Jun 19, 2022 9:16 pm

Understood, thanks Bob
Bob
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Re: tyres question

Post by Bob » Sun Jun 19, 2022 9:18 pm

👍
teenmal
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Re: tyres question

Post by teenmal » Sun Jun 19, 2022 11:33 pm

Mazda and other vehicle manufactures by law must display all Tyre specifications for that particular vehicle ,they have spent a great deal of time and money perfecting the performance and safety aspects of their vehicles, changing the spec can have serious implications , it is also illegal to have the wrong Tyre pressures. Its really up to yourself what you do its your choice but you are responsible for your actions. Take care.
bobby_badger
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Location: Dorset

Re: tyres question

Post by bobby_badger » Mon Jun 20, 2022 8:25 am

Understood. In an ideal world everyone would stick exactly to the manufacturer's instructions but I see a lot of people use the same on all four tyres and in fact the fact sheet from Bongo Fury says as much. Replacing all four tyres, which are working perfectly and don't need replacing yet from a tread point of view, just to comply 100% with Mazda is not something I'd want to do unless I absolutely had to, and it doesn't seem like that's the case.

But I'd be very happy to hear what others do, or would do in my situation.
teenmal
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Re: tyres question

Post by teenmal » Mon Jun 20, 2022 11:47 am

As I have said ..Its really up to yourself what you do its your choice but you are responsible for your actions. Take care.

It is also advisable to inform your Insurance Company of your modification or intentions, failure to do so could invalidate your Policy.

Just stating facts to help you into an :lol: Ideal World. :-({|=
Hazzobongo
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Re: tyres question

Post by Hazzobongo » Fri Jun 24, 2022 3:12 pm

Mazda don't stick by their own recommendations as my spare is one of those skinny ones to get you to a tyre shop, if it was so important the van would be equipped with a proper size wheel imo.
teenmal
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Re: tyres question

Post by teenmal » Sun Jun 26, 2022 10:46 am

Hazzobongo wrote: Fri Jun 24, 2022 3:12 pm Mazda don't stick by their own recommendations as my spare is one of those skinny ones to get you to a tyre shop, if it was so important the van would be equipped with a proper size wheel imo.






Check out Mazda recommendations for their Spacesaver ,as with all vehicle manufactures they have to give precise instructions to the use of this particular wheel/tyre. or it would never hit the road Jack.

The majority of new cars don't even have a spare wheel .
Hazzobongo
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Re: tyres question

Post by Hazzobongo » Sun Jul 03, 2022 4:14 pm

My last three new cars never had a spare and if I had to fit that 'spacesaver' I'd be sticking to 30 and 40 till I found the nearest tyre fitters, I rejoined the AA thanks to those cars and the solutions to flats these manufacturers supply.