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Alexander

Really quick tyre question!

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Hi all,

 

Well, the C is in for MOT and service today, sailed through MOT only needing a headlight bulb :D

 

However, 3 of my tyres are very low, so I'm going to have to bite the bullet and buy her some new shoes.

 

The question is this - currently, I've got different sized tyres on the front than on the back. Why? I have no idea, I bought the car like that. It's got (I think) 195/45/15 on the front and 205/50/15 on the back. Which is "correct"? Is there anything wrong with having bigger tyres on the back?

 

As I say want to get this sorted today so a swift response from one of you clever bods would be appreciated!

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I should point out, although it looks like the car is on standard G60 BBS's, they're actually off a BMW, got a bit of a dish to them and they're wider than normal, 15x7 if I remember right.

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All the wrong sizes!

 

Should be 195/50/15... out the box... so your speedo will be out as the lower front profiles will give a smaller rolling radius...

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Yeah sorry, you're right - my mistake, it's currently got 195/50/15 on the front, 205/50/15 on the back.

 

You're saying 195/50/15 all round then? Bearing in mind my wheels are wider than standard G60 ones?

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Yup will be fine on 7's

 

Running 195/45/16 on my 2 sets of 16x7's

 

Toyo PX4's are pretty cheap in 195/50/15 ATM and a great tyre too! Had them on my Estorils

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Thank you mate, appreciate your help.

 

Just looking at the prices on etyres.co.uk - a lot cheaper than the garage is quoting me for Toyos! Might grab it back off the garage and get etyres out tomorrow to sort the rubber.

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This is fairly easy... go check the Wiki... HERE. There used to be tyre size calculators too, but I cannot get the links to work on my PC. If you go into the Tyre Bible at the bottom of the Wiki, there used to be a calculator in there.

 

Yawn... Basically you just said you've got 195 versus 205 - thats a whopping 10mm, or also known as 1cm. It really is small beans and not a big worry. Both would work on the standard 6.5 wide wheel; but you've got some BMW's at 7 wide, and therefore I can tell you that 205 works perfectly well and 195 is the minimum I'd try. I wouldn't mix, but if you're forced to, then this 1cm difference is minimal.

 

What tyres to buy; I'd consider matching the 3 tyres to your ok tyre. If the 4th tyre size is wrong, then replace all 4. If money wasn't an issue I'd go buy 4 new tyres for an even feel and SAFE ride.

 

In summary I'd always keep my tyres the same - same size, same brand. Read the tyre bible and you'll see why; theres muff about slip angles etc, but in summary the handling will be sorted and even. For better handling, people look to stickier tyres, then stiffer-side-wall tyres, lower profiles (on bigger wheel dias).

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Thank you matey, will check the wiki.

 

I'm going for all 4 new tyres, because they're all cheap and nasty and the 4th one can't have too much left on it anyway. I've never driven a car with decent tyres on so I'm interested to see what difference it makes.

 

I think I'm going to go for 4x Toyo T1-Rs, they seem to get pretty good reviews and they're a good price on etyres.co.uk. From what you're saying it's pretty much a free choice between 195 and 205 on 7" wide rims, as long as they're all the same. 195s are quite a bit cheaper so I think I'll just go for that.

 

Thanks a lot!

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I'd go with PX4's TBH, they as good dry weather and better wet.. and think tehy come out cheaper too as well?

 

I vouch for their wet performance... solid even with standing water!

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I'd go with PX4's TBH, they as good dry weather and better wet.. and think tehy come out cheaper too as well?

 

I vouch for their wet performance... solid even with standing water!

 

I've now heard loads of good reports for the PX4s in the wet... May have to consider some myself next time round...

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Have a look at the dedicated tyre thread - I've found Toyos to be very soft and wear out incredibly quickly - based on experience with 2 cars. I'm on Contis now and they're much better. Tyres aren't really something I like skimping on TBH.

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Toyo PX4 (also known as Pro-ox 4's)

 

Next Generation after the T-1R...

 

Had some T-1S on the rears for a while (on my Compo) and noisier than PX4's so guess the T-1R with harder side walls will be noisier again..

 

PX4's lasted a good 10,000 on the front... just make sure if you get 4 to rotate (as you should with all tyres to get max life)

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Neil - which Contis in particular?

 

Isn't there always a trade off between grip and longevity, though? I mean the tyres I've currently got have lasted years, but then they do seem to be made out of plastic. I don't mind changing tyres more frequently if they're grippier, and safer (and quieter).

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Alex

 

Did you read the wiki? Theres actually some good stuff there; and if you had time you'd find some interesting stuff in the Bible.

 

Never had new tyres? Well enjoy; and having 4 the same makes a difference. Just remember most new tyres can feel odd and slippery; the massive deep treads can seem to make the blocks wobbly; depends on the tyre make and rubber solidity.

 

You're pondering over Toys, then Proxis etc. If you read the sticky thread on tyres you'll get some feedback on tyre life and performance (for instance I got about 5 or 6k miles out of Toyos compared to 11k on the front with Uni). The Toyos Proxis tend to be sticky, but dont last long. The Uniroyal Rainsports last a little longer, but maybe not as solid - however do shift water easily (the Toyo PX4s look similar). Then theres Eagle F1's if they do your size - a great all rounder. Then you get into Conti, Michelin (SP'1 - not the 2's), Bridge' etc - these pricey boys tend to last longer, but also you'll find they have a stiffer side wall and general good construction, giving a stable ride.

 

Enjoy your purchse and post on the Tyre sticky thread with feedback after a month or so.

8)

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Thanks Stuart, yeah loads of great info in there. Went for the Toyo PX4s after all, I'll see how they wear! At only £40 a corner from mytyres.co.uk I'm not too fussed if they only last a year.

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Yeh, tonnes of links, sorry. Look forward to feedback.

Yep, 40 isnt bad (even if you add 40 for fitting all), and much better than the 160/corner i was paying for some michelin 245/40/17 SP1s. :gag:

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OK looks like I've failed epically here!

 

Bought 4 at 195/50/15 and went this morning to get them fitted at my local (trusted) tyre fitters. The guy there said they're the wrong size, and didn't advise fitting them because my speedo would be out! Bearing in mind he passed up £60 to tell me this, I can't see why he'd lie :(

 

So, it looks like 205/50/15 is correct for my 15x7 wheels then, so although my C has 205s on the back and 195s on the front, I picked the wrong pair to be correct. Bah.

 

Looking at the wiki, the VR6s came with 15x7s as standard, and they were on 205/50/15 so I should really have picked up on this myself. Feel like a bit of a knob, but hey ho.

 

Anyone want to buy some Toyo PX4s? :D

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He's talking boolox mate... probably wanted you to buy some off him instead... 195 are correct for a G60/16v... so your speedo will be spot on. He must be doing well not to want your money, plenty of other fitters will do it!

 

Go find another tyre fitter... My local Kwick-fit even fitted a set of 195's to my 7" wide Porsches so there's no issues with width...

 

Yes a 7" should "Technically" have a 205/215 tyre on it but that's rubbish a 195 sits fine with almost no stretch!

 

See my Gallery for the Porkers and the Compo's they both have 195 tyres, my LM's which were 7.5's had 205's again no stretch!

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Aye yeah that's what I'm saying, 195 is correct for a g60, but they came with 6.5" wheels, unless I'm being dense.. mine are 7" wide like the vr6, which took a 205 out of the factory? I really don't want my speedo to be out, that's my main concern.

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OK so if it came with a 195/50/15 tyre then the speedo's set for a 195/50/15... so you'll be fine!

 

The difference isn't much TBH... I was running 17's with 205/40/17's and speedo read 40 and speed was 38 (according to roadside radar)... so don't stress...

 

Stay with what you have bought they are correct for the car, and won't make a difference if on a 6 or 7" wheel..

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Chill out and blame your self, lol. Try reading all those links I gave you. Then you'll be well eqipped next time some idot tries to palm off some Nasty-Tyres off on to you.

 

195 versus 205.... like I said, wow all of 1cm difference. And you've got a wheel all of half an inch wider too. Its not going to make all that much difference. You know the speedo should be about right - so that just leaves the 'stretch'.

 

If you find one of the old tyre size calculators, (eg the Bible), you'll see that if you change wheel sizes you actually change the speedo reading anyhow, as its millimeters difference. For instance, the well trusted tyres sizes in the wiki; try putting in 205/50 versus a 195/50 versus a 195/55 ; they all give tiny different speedo readings. Why? Because remember that the 50 stands for the side wall height, as a percentage - that is 50 percent of 205 which is 102.5 versus 50 percent of 195 which is 97.5. You're changing the diameter of the tyre here and thus the cirumference too (rolling radius).

 

I think going by those tyre widths in the wiki, you could technically go up to a 215 wide tyre; but it'd look crazy. And you might need to drop to a 45 profile at that point; not sure, you'd have to calculate it. I cannot get onto the Tyre Bible site from work to check for you. And the lower limit of width recommended? Not sure; but certainly 205 works. So if you've got 195, a 1cm difference (at worst); that equates to a huge 5mm stretch to either side of the tyre... not so huge huh.

 

In summary, yes the 195 might be a strech, hence I said I personally went for 205's on my 7j BBS. I personally do not like a strech for handling reasons - but most people like a stretch for the look. People go for a far bigger stretch that what you've bought - much bigger. Try finding some photos on here and you'll see what I mean. Rest easy and go get those 195's fitted*. Next time, dont dilly-dally over £5/tyre difference.

 

* Im sure I said go to a trusted fitter, lol. Go somewhere decent. Look on forums etc for ideas. Roll up in person and ask. £15/corner isnt bad.

The place I went, the guys donned white gloves and used rubber-end protected levers; not a single sign of a scratch on my wheels anywhere. Compare that to Britannia Tyres in Coventry and ouch, they're animals.

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22042009141.jpg

 

In the foreground is a 195/45/16 on a 7" as you can see no "stretch" as such... only small issue is that the lips of the rims aren't as protected as they would be with a 205... however from memory the Toyo PX4 has "rim protectors" which sould sort that!

 

So in short don't worry... be happy! Get them fitted!

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Perfect, those 195's look fine on the 7 wide rim. And the photo I sent you, the 205's looked chunky on the 7 wide rim; yet they work. From a practical point of view, you can clearly see 195 works; however, the numbers are below:

 

Now I know you've made your decision, but for the benefit of any other new raddo folk:

 

I'll say it once more; the speedo difference is tiny.

50 percent of 195 is 97.5mm

50 percent of 205 is 102mm

 

Thats a whopping 5mm (0.5cm) difference in tyre wall height. Yes the diameter of the 195 ends up being less (actually 1cm in total), but its not biggie.

 

Technically you'd need a 195/52/15 ... but they don't do a 52 percent sized tyre wall. Hence Im sure VW say that 195/50 is fine too. (forget about your rim width, its not related - rim width is concerned with the tyre being stretched or not). The ratio of 195/50 is fine.*

 

Hence I was concentrating on the stretch factor of a 195 onto a 7 wide rim. Its a tiny stretch as said before; as you can see my 205's looked chunky. Not only that, but you will find different tyre manufacturers measure the width differently, and so line up a Michelin back to back with a Dunlop and you might find the Dunlop is narrower of a couple mm; no worry.

 

================================

* if or when you increase your rim diameter (not width), from 15 to 16 inch, then you have to reduce the tyre wall height if you keep the tyre width the same; for example a 205/50/15, going onto a 16 rim you'd need a 205/45/16 (thats 5 percent reduction on 205, which is 10mm on the tyre wall height; but look at your wheel and you can see tyre wall at the top and the bottom, so double that figure of 10 and you get 20mm reduction in tyre height, which is roughly counteracting the 1 inch wheel increase)

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so what if your speedos out, all the speed cameras give you 10% anyway ;) as long as you dont go above the limit on the speedo you will be fine dont worry about that!!

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