Tyres - do I have a problem?

scanner · Post by **scanner** » Fri Feb 29, 2008 6:50 pm

pete wylie wrote:This is the plate on my Bongo.

http://s268.photobucket.com/albums/jj20/petewylie/

Strange, yours only shows the size that is the option on Trev's and mine.

trevd01 · Post by **trevd01** » Fri Feb 29, 2008 9:15 pm

Pete's is a 99 V6. Which by definition is 2wd. Ours is a '99 diesel 4wd.

So perhaps that bigger tyre diameter is specified to suit the V6 gearing.

Anyway I have finally decided one thing today:

The tyre size difference is nothing to do with 'pre-loading' the 4wd. (its less than 1% anyway).

It is to provide 'safer handling' characteristics, i.e. under-steer.

That is my considered view ...I did kinda like the pre-loading idea, but...

Why do 2wds have different front and rear tye sizes, if it isn't for 'safer handling'?

That's my view and I am sticking to it

dandywarhol · Post by **dandywarhol** » Sat Mar 01, 2008 1:48 am

trevd01 wrote:Pete's is a 99 V6. Which by definition is 2wd. Ours is a '99 diesel 4wd.

So perhaps that bigger tyre diameter is specified to suit the V6 gearing.

Anyway I have finally decided one thing today:

The tyre size difference is nothing to do with 'pre-loading' the 4wd. (its less than 1% anyway).

It is to provide 'safer handling' characteristics, i.e. under-steer.

That is my considered view ...I did kinda like the pre-loading idea, but...

Why do 2wds have different front and rear tye sizes, if it isn't for 'safer handling'?

That's my view and I am sticking to it

Hmmmmm......why do Freelanders have different ratios in the front and rear diffs but the same tryes all round

Bongo Boozer · Post by **Bongo Boozer** » Sat Mar 01, 2008 10:57 am

David,
were did you get the NANKANG tyres from for that price?
I have found the below but they are £37 each + £40 to deliver + me to get fitted.
XR611 NANKANG XR 611 - 205/65R15 96H

I need a set soon before I go to France so if you could let me know that would be great.

Cheers
Steve M

scanner · Post by **scanner** » Sat Mar 01, 2008 2:20 pm

Bongo Boozer wrote:David,
were did you get the NANKANG tyres from for that price?
I have found the below but they are £37 each + £40 to deliver + me to get fitted.
XR611 NANKANG XR 611 - 205/65R15 96H

I need a set soon before I go to France so if you could let me know that would be great.

Cheers
Steve M

£37 seems to be the right price but no extra for delivery from here.

http://www.camskill.co.uk/products.php?plid=m4b0s422p0

Still got to get them fitted though.............

mikeonb4c · Post by **mikeonb4c** » Sat Mar 01, 2008 7:24 pm

trevd01 wrote:Pete's is a 99 V6. Which by definition is 2wd. Ours is a '99 diesel 4wd.

So perhaps that bigger tyre diameter is specified to suit the V6 gearing.

Anyway I have finally decided one thing today:

The tyre size difference is nothing to do with 'pre-loading' the 4wd. (its less than 1% anyway).

It is to provide 'safer handling' characteristics, i.e. under-steer.

That is my considered view ...I did kinda like the pre-loading idea, but...

Why do 2wds have different front and rear tye sizes, if it isn't for 'safer handling'?

That's my view and I am sticking to it

You may well be right Trev. But the way I see it, if I had 4WD I'd be much more concerned to follow the manufacturers recommendations in case the 'wind-up' theory was valid (Dandy is in the trade after all). With a 2WD, I'd just go with how I felt about the handling. Mine has the same tyres all round and handles very well from all I can see.

John the sparky · Post by **John the sparky** » Sat Mar 01, 2008 9:10 pm

I have 225/55 16s all round on a 2 wheel drive......

I didn't get into a situation where I was pushing the front when I was running on standard correct tyre sizes.... so I'll take a chance,

I'm sure if it lets go now though.... I'll be in orbit

DemonAV · Post by **DemonAV** » Wed Mar 05, 2008 9:41 pm

This is translate from japan catalog about Friendee:
To increase the stability of the car traffic on expressways highways used diferent size wheels on the front and rear axles. The vehicle has a fairly large weight and wheel base of 2920 mm and a height at the expense of it is highly sensitive to the lateral wind. To compensate for this feature, establishes more high wheels to the rear axle, and the lower front. (translate from japan to russian, than from russian to english

)
We use one size for all wheels, and all work great.

dandywarhol · Post by **dandywarhol** » Wed Mar 05, 2008 9:49 pm

Thanks Demon - that stuffs my Viscous Coupling theory

mikeonb4c · Post by **mikeonb4c** » Wed Mar 05, 2008 11:41 pm

DemonAV - yet again you have come up with a definitive answer to an old, much debated issue.

I don't think you should be too hard on yourself Dandy. In the absence of knowing, all that's really being said is that if there is a possibility that fitting incorrect tyres may affect the viscous coupling then best to stick to spec. if driving 4WD. And there have been some problems in that area so its reasonable to speculate.

As DemonAV says, they seem to handle fine with same tyres all round. It's be interesting to see how much better they handle with proper spec. tyres on

Veg_Ian · Post by **Veg_Ian** » Thu Mar 06, 2008 8:49 am

Well I have a 4WD and until recently had standard spec tyres on. Following advice from chums on here I now have 215s all round. I notice it now tends to "wallow" a bit at low speeds despite running with 35psi at the front and 40psi at the back. However at motorway speeds the ride is a lot better and softer. I certainly don't regret the change.

Rhod · Post by **Rhod** » Thu Mar 06, 2008 8:00 pm

So I can leave my hardly worn 195/215s on until they're actually worn, without worrying too much then! Better change the 205 spare that it came with though! Now, a 195 or a 215 spare

On a bike it's always the rear that is more prone to puncture (you tend to steer the front clear of debris) - wonder if the same is true of a 4-wheeler

Rhod

scanner · Post by **scanner** » Thu Mar 06, 2008 8:10 pm

Veg_Ian wrote:Well I have a 4WD and until recently had standard spec tyres on. Following advice from chums on here I now have 215s all round. I notice it now tends to "wallow" a bit at low speeds despite running with 35psi at the front and 40psi at the back. However at motorway speeds the ride is a lot better and softer. I certainly don't regret the change.

I use about 35psi all round with 215s and find it's OK at all speeds.

DemonAV · Post by **DemonAV** » Thu Mar 06, 2008 8:30 pm

Manufacturer recommends installing at the front and rear axle different sizes, it is true difference in the length of the circumference of no more than 1%. And for 2WD car, and 4WD. The theory and practice show that the installation of wheels the same size on both axles does not lead to deterioration car behavioural, but noticeably simplifies search tires. Because transfer box no rigid connection between the front and rear axle, the error will not affect the work itself transfer. Ongoing experiments on measuring temperature transfer while driving on the recommended dimensionality and on the same wheels, were within the error of measurements. http://www.excite.co.jp/world/english/w ... N&wb_dis=2

dandywarhol · Post by **dandywarhol** » Thu Mar 06, 2008 9:08 pm

Wow...........excellent website Demon - so much to browse through hand the translating is erm........ amusing!

This is the bit on the VC temperature when using different tyre configurations - scientific in a practical way - I like it! So it seems the difference in VC temperature is minimal if the tyres are standard size or all the same.
I'd be curious to know how it would be affected by a set of worn tyres on the front axle and new on the rear

I had a look at the overheating info....