tyres

[Phil Garwood]

hi people i need some help with tyres i have alloy wheels on my bongo but the tyre sizes are 245/45 zr18 100y
my bongo is 4wd ive looked on members pages but carnt find anything are these tyres the right size please
can anybody help?

[francophile1947]

Welcome to the madhouse
According to http://www.tyresave.co.uk/tyresize.html your tyres are 2.57% too large compared to standard, so are probably about right Just check that your speedo is not under-reading.

[Phil Garwood]

ok thanks i will check speedo i think it is reading wrong cos its not the same as my tom tom but
i carnt remember if it is faster or slower

[borntobag]

" your tyres are 2.57% too large compared to standard" or do you mean, larger than standard?, bit of a difference.

I run 235/50/18s on mine, a little bit narrower and a bit taller in the side walls than your 245/45/18s.

I found the original 245/45/18 tyres that came with my alloys a bit of a harsh ride, so I upped the side wall ratio a bit and ended up with the 235/50/18 tyres I have on now.

The only draw back was I had to trim off about 3/4 " off the inside edge of the bumper to allow full lock without rubbing the tyre, easily done with a hack saw, jig saw or stanley knife, choose your weapon.
In addition I have fitted a splitter off a Renault Espace and you really cant tell its been doctor'd.

I had to fit spigot rings to take up the difference between the bore of the alloys and the slightly smaller bongo hub. If you dont, it will shake like a yob in a magistrates court as the wheels are only constrained by the nuts alone (shame the yobs cant be as well).

Other than that, make sure the spare tyre is the same or has the same rolling circumference as the running 4. Its a constant 4x4 wheel drive and you could/will damage your transmission if 3 of wheels are rotating at the same rate but covering a different distance compared with spare you put on.

Spare tyre wise, try to get a omni rotational one so it can be mounted on either side, it wount make much sort term difference if you have a rotational tyre and fit it on the wrong side, just not as grippy as it could be, makes a bit more road noise and will wear out much faster. A lot of drifters do this on purpose, to get the car to slide and to smoke the tyres more.

I had a problem with placement of my spare wheel as the hanger wouldnt go through the centre of the alloy, I just ground out one of the coils in the hangers spring and it fits fine now.

Speed wise, speedo reads 70mph, gps reads 68mph, fine in my book as it was 8 mpg out before.

I run them all at 40psi and cant fault them.

Hope this is of some help,
Regards Rob

[francophile1947]

" your tyres are 2.57% too large compared to standard" or do you mean, larger than standard?, bit of a difference.

Really Perhaps you'd care to elaborate?

[borntobag]

I realise it was just a quote,
but why are they TOO large compared to with standard ones, this implies there could be a problem so dont do it, does it not? rather than just saying they are 2.57% bigger.
I havnt had any adverse effects using bigger tyres and wheels, the bongo tracks better, has slightly better mpg and i like the looks.
Just the way it read, not having a personal dig at you.

[francophile1947]

I realise it was just a quote,
but why are they TOO large compared to with standard ones, this implies there could be a problem so dont do it, does it not? rather than just saying they are 2.57% bigger.
I havnt had any adverse effects using bigger tyres and wheels, the bongo tracks better, has slightly better mpg and i like the looks.
Just the way it read, not having a personal dig at you.

Definitely doesn't imply that - merely that they are too large compared to the standard size. I have had 235/55x17s fitted (4.39% too large) with no problems so, if it was a problem, I would have mentioned it.

[borntobag]

I think we are getting crossed wires here John.

You quoted:
"According to http://www.tyresave.co.uk/tyresize.html your tyres are 2.57% too large compared to standard"
and even said yourself "I have had 235/55x17s fitted (4.39% too large)"

This is a direct quote from a tyre companys web site which compares replacement tyre sizes with the original tyre size and has been cut and pasted and used incorrectly and out of context , especially as you backed it up with "merely that they are too large compared to the standard size"

No they are not, not at all, they are larger than the standard size, simple..end of.

I will try to explain what i mean as best i can,

If you took a standard 15" wheel with a damaged tyre into tyresave or kwik fit etc..and asked them to put a 245/45/18 tyre on it they would laugh and say "sorry mate its 2.57% TOO large compared with standard 15" one and will not fit".

If you put a 15" spare wheel and tyre on your bongo as a replacement for one of your 235/55x17s it would have a differnent rolling circumference than the other 3 and will be TOO small in comparison and could cause problems or damage to your transmission.

but by replacing all the original 15" wheels and tyres with 16" or 17" or in Phils case 18" wheels and tyres, they will not be TOO large at all, they will fit just fine, just simply be 2.57% larger than the originals.

So yes John, there is a difference a big difference
Phils 18" wheels and tyres are not TOO large for his bongo they are simply larger than the original 15" fitment.

If he is happy with them and they run fine and dont adversly effect the Bongos steering and braking etc then there is no problem using them, i just found the tyre wall ratio on a 245/45/18 was too harsh a ride so i opted for a 235/50/18.

TO do this i replaced the front and rear TWO at the same time or they would be TOO friggin large compared TO the originals and could cause problems.

[waycar8]

As long as ALL 4 tyres are the same size on the 4wd bongo only problems will be that the speedo will be out by a few mph. but this can be made correct by gently pulling off the speedo needle using the handles of 2 t spoons or similar then drive to a long empty rd with a passenger in the bongo with you where you can get it up to 30mph with the aid of a sat nav, then get your passenger to hold the steering wheel while you the driver put the needle back on with it facing the 30mph when your up to 30 mph.

[Driver+Passengers]

As long as ALL 4 tyres are the same size on the 4wd bongo only problems will be that the speedo will be out by a few mph. but this can be made correct by gently pulling off the speedo needle using the handles of 2 t spoons or similar then drive to a long empty rd with a passenger in the bongo with you where you can get it up to 30mph with the aid of a sat nav, then get your passenger to hold the steering wheel while you the driver put the needle back on with it facing the 30mph when your up to 30 mph.

What page of the manual is that on??