PDA

View Full Version : BFG 265/75/R16 on the Fender?



Greylandy
7th June 2004, 05:18 PM
Anybody got experience with 265/75 BFG muddies on a TD5 Defender (16' alloys)? Any issues with rubbing on the radius arm? I was looking at 255/85 but have been told more than 15mm in diameter would make the setup unroadworthy.

Any suggestions...

rmp
7th June 2004, 09:02 PM
Henry, you're correct re the 15mm. The 265/75/16 are the same diameter as the 235/85/16, or very nearly. The additional width shouldn't be a problem in terms of flares. I don't think it'll fit on the stock rim, but ask a dealer. The wider tyres will give better on-road handling but slightly decrease fuel economy. I doubt offroad ability will be affected one way or the other. Post your results back please.

HSVRangie
8th June 2004, 09:32 AM
265/75/16 fit on 7 inch rims no problems.

Yes they will rub on radias arms.

Michael.

Greylandy
8th June 2004, 05:35 PM
Thanks gents .. I reckon they will be the go.

VladTepes
16th June 2004, 03:47 PM
Originally posted by HSVRangie
265/75/16 fit on 7 inch rims no problems.

Yes they will rub on radias arms.

Michael.

to what extent will they rub ? is this a problem ? what needs to be done to fix it ? (I understand this whole tyre thing not at all).

How do 265/75's compare to 235/85's ? wider i take it ? what else ?
is the overall rolling diameter the same or will it affect speedo etc.

Please tell me. I am stupid. :oops:

rmp
16th June 2004, 03:58 PM
Originally posted by VladTepes+--><div class='quotetop'>QUOTE(VladTepes)</div><div class='quotemain'><!--QuoteBegin-HSVRangie
265/75/16 fit on 7 inch rims no problems.

Yes they will rub on radias arms.

Michael.

to what extent will they rub ? is this a problem ? what needs to be done to fix it ? (I understand this whole tyre thing not at all).

How do 265/75's compare to 235/85's ? wider i take it ? what else ?
is the overall rolling diameter the same or will it affect speedo etc.

Please tell me. I am stupid. :oops:[/b][/quote]

265/235 = diameter in mm
75/85 = aspect ratio in %
16 = rim diameter in inches

Total diameter = 265 + ((265*0.75) *2) + 16 inches

235/85/16 (never forget the rim size) is the same diameter is 235/85/16, or very very close.

Wide tyres generally have better on-road handling, but are heavier and greater drag. Wide vs thin is an ongoing debate. Wide tends to look better and more "serious".

32 x 11.5 x 15 is 32 inch diameter, 11.5 inches wide, on a 15 inch rim.

LT = light truck (good)
P = passenger (bad, weak)

and no apostrophe required to pluralise 235/85s!

etc.

VladTepes
16th June 2004, 04:52 PM
Originally posted by rmp
235/85/16 (never forget the rim size) is the same diameter is 235/85/16, or very very close.
.

D'uh :!: style_emoticons/<#EMO_DIR#>/tongue.gif


32 x 11.5 x 15 is 32 inch diameter, 11.5 inches wide, on a 15 inch rim

What's that in metric - why are sometimes quoted metric and sometimes imperial ?

rmp
16th June 2004, 05:11 PM
Originally posted by VladTepes+--><div class='quotetop'>QUOTE(VladTepes)</div><div class='quotemain'><!--QuoteBegin-rmp
235/85/16 (never forget the rim size) is the same diameter is 235/85/16, or very very close.
.

D'uh :!: style_emoticons/<#EMO_DIR#>/tongue.gif


32 x 11.5 x 15 is 32 inch diameter, 11.5 inches wide, on a 15 inch rim

What's that in metric - why are sometimes quoted metric and sometimes imperial ?[/b][/quote]

Why imperial and metric.

Why was imperial ever invented in the first place.

Why base 10.

Why a GST.

Why do we have steering wheels on the left.

Why is the brake pedal in the middle.

Answer; no idea, it's just the way it is, some weird historical happenstance I expect!

I shall send you my Tyre Calc spreadsheet.

Defender200Tdi
16th June 2004, 08:39 PM
<div class='quotetop'>QUOTE</div><div class='quotemain'>265/235 = diameter in mm
75/85 = aspect ratio in %
16 = rim diameter in inches

Total diameter = 265 + ((265*0.75) *2) + 16 inches [/b][/quote]

Not quite.

265 = Width in mm, not diameter.

Aspect ratio is the height of the sidewall as a percentage of the width. Thus 265/75 has a sidewall height of 75% of the 265mm width. 235/85 has a sidewall height 85% of the 235mm width. Both have a rolling diameter approximately the same, which is also approximately the same as 7.50R16.

Therefore 265/75R16 has total diameter of ((265*0.75)*2) + 16 inches. That's about 804mm or 31.7".

Most 15" offroad tyres quote the imperial (US) sizes because that is what is used over there the most. The rest quote metric (Euro) sizes because that's what the rest of the world use.

The old imperial (non US) tyre sizes like 7.50R16 and 9.00R16 assume an aspect ratio of 100%, hence no ratio is quoted. Modern metric sizes that do not quote an aspect ratio like 205R16 have an aspect ratio of 80% and they don't quote it just to confuse everyone. :?

<div class='quotetop'>QUOTE</div><div class='quotemain'>to what extent will they rub ? is this a problem ? what needs to be done to fix it ? (I understand this whole tyre thing not at all). [/b][/quote]

265/75 will rub a little on the radius arms at the front on full lock. It's not really an issue and you can ignore it and just avoid full hard lock when turning, or prevent it by adjusting the lock stops on the front. This takes about fifteen minutes including jacking up the front and putting the stands under. There should be no issue at all for the rear tyres.

That's probably confused you even more. style_emoticons/<#EMO_DIR#>/tongue.gif


Paul style_emoticons/<#EMO_DIR#>/biggrin.gif

rmp
16th June 2004, 10:39 PM
Yes, my mistake, should have been width, and more specifically, tread width not section width. 235mm isn't a very large diameter for a 4WD tyre.

I think the strangeness is the mix of metric and imperial for 235/85/16s.

And the formula was wrong as well:

275/75/16
((265*0.75) * 2) + 16 inches

BTW the "R" stands for Radial.

A 32x11.5x15 is equivalent, roughly, to 285/70/16 but I'm not sure such a tyre exists, have a look on something like Coopers' website.

VladTepes
17th June 2004, 09:42 AM
I shall send you my Tyre Calc spreadsheet.


and then


That's probably confused you even more. style_emoticons/<#EMO_DIR#>/tongue.gif
[/quote]