Evening all my virgin post so please bear with if I make mistakes

I've been looking at some 285,50,20s for my sport I'm sure some one on here posted that they had fitted some , but I can't remember if they said they had trouble with arch rub under full articulation ?

Any help would be gratefully received as I'm looking to try and increase my side wall as much as possible , I'm fed up with puncturing tires because the 40's side walls are far to narrow

Thank you

I believe there are guys on the Disco forum that run this size but no idea on a sport. I would imagine that your problem would be when going lock to lock that it would rub hopefully someone more experienced will be along to help you out soon  2003 BMW M5 - 5 Litres of V8 Optimax Slurping Goodness in Carbon Black

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Thank you I hope so
I did try and see if the subject had been covered before but can't seem to find a search the forum box any where

Hey Mate

I had them on my old Sport, just sold it for a new one .

It was an MY10 , 285 50 20 Cooper Zeon , rubs at full lock when shifting (ie if you move slowly its fine, but once suspension loads up under full lock it rubs on the front of the chassis rail that protrudes under the footwell, if you get an angle grinder on it it wont at all, though I never bothered and had them on for 50,000 kms and all was good, plenty of heavy sand and dune work at low pressures (10 psi).

Gonna get similar for my new one as well

If you look back through my posts you will find the photos of them on the car, looked awesome !

Fantastic thank you for your quick reply I will look back through & have a look

Just a thought do you think a wheel spacer would solve the rubbing issue ? Say 20mm or do you think it would make the tyres stick out past the arches far too much ?
Ooo also will the spare still fit in its recess underneath the rear ?
Cheers

I didnt have a matching spare so couldnt tell you.

I doubt a spacer would be much good, and I also dont think it would be a good idea.

Better to just get the grinder onto it, it only protrudes a few cm so it wouldn't be hard to smooth off.

I just didnt go full lock at any sort of speed or that often.

hairy bum wrote:

Ooo also will the spare still fit in its recess underneath the rear ?
Cheers

I've squeezed a 275/65R18 up into the spare well (albeit fully deflated and with a lot of swearing), and that's 814mm diameter. So I wouldn't think there'd be too much involved in fitting a 285/50R20 (793mm). I removed the heat shield and as mentioned, deflated the tyre - no need to cut anything.

Cheers,

Gordon 2015 RRS SDV6 SE, Santorini Black, GOE 2-way HS rods, Traxide dual battery, 275/55R20 Nitto TerraGraplers

2015 Discovery 4 SDV6 HSE - GOE 3-way HS rods, GOE underbody plates and sliders, 275/65R18 Courgia MT

I can see why people stick to 275x45 I don't mind a little bit of a Challenge , what could possibly go wrong

I do take it if I've got it in in " rock " mode so anti roll bars are disconcerted there is no rubbing issues on the arches on full articulation ? that your aware of ...

disco4x4au wrote:

I've squeezed a 275/65R18 up into the spare well (albeit fully deflated and with a lot of swearing), and that's 814mm diameter. So I wouldn't think there'd be too much involved in fitting a 285/50R20 (793mm). I removed the heat shield and as mentioned, deflated the tyre - no need to cut anything.

Cheers,

Gordon

Oh dear that's not good .. Now I understand why most people go for the 275-45's instead .. This looks like a lot of work

It really isn't as hard or difficult as it sound's just a lot of trial and error i.e up and down with the wheel until it fit's in. I think the main issue would be not removing to much from the rear tie bar bracket's, although they are quite substantial I would be concerned that removing to much would weaken them, although saying that I did mine some time ago and have checked them regularly as a precaution and have no issues.

I don't think I would attempt to fit a 285/50 but you could use a 275/50 x 20 which is only 2mm bigger diam. than the 21" I fitted. I suppose you could also use a worn tyre down to a couple of mm (I used a brand new tyre) or so if it is only for a spare which would help with the space.

Cheers
Col

Double post.

Last edited by Oz Sport on Fri Dec 11 2015 10:35pm. Edited 1 time in total

I always have my compressor in the car as I am regularly off the road.

I beleive Disco is the same as his was near the most complete offroad RRS I have seen without significant changes to the car.

The only reason for a 285 50 is iff you go offroad. The extra sidewall makes a big difference.

Col wrote:

disco4x4au wrote:

I've squeezed a 275/65R18 up into the spare well (albeit fully deflated and with a lot of swearing), and that's 814mm diameter. So I wouldn't think there'd be too much involved in fitting a 285/50R20 (793mm). I removed the heat shield and as mentioned, deflated the tyre - no need to cut anything.

Cheers,

Gordon

Am I missing something here? as I am under the impression a spare is carried in case you damaged a wheel or puncture a tyre, it seems a pretty pointless exercise to carry a totally deflated spare unless you carry a compressor or some means of inflating it as well.

There is no way on earth you will get a fully inflated 285/50 x 20 into the space without modifying something. To get in a 275/45/ x 21 (781mm diam.) fully inflated. I had to grind and smooth off the weld where the tow hitch receiver is welded in to the rear cross member, reshape the heat shields and grind and re-shape the rear tie rod brackets slightly where they are welded to the rear sub-frame this is due to the increased Radius of the new inflated size wheel/tyre.

Cheers
Col