Tyre Advice

[JohnC]

On 11/13/2024 at 5:33 AM, jerrytr5 said:

Having read the Longstone article, I think that there is a degree of economy with the truth going on.

I refer to the statement "Some TR6 owners install 185/70R15 or 195/65R15 tires. We believe that if bigger tires enhanced the TR6's driving abilities, Triumph would have installed them as standard."

I recall in the late '70's early '80's it was almost impossible to get 15 inch tyres as almost all cars of the period ran on 13 inch. I don't know when profiles lower than 80% were introduced but when the TR6 was in production I suspect the only car using 70 profile with a 15 inch rim would have been the XJ6 on 205/70, which I did have to resort to on my 4A as nothing else was available/affordable for the average driver (perfectly safe on those narrow rims, Officer).

To suggest that BL might have re-assessed the tyre on an outgoing model does not seem realistic to me particularly as 70% profile was in it's infancy and 65% not yet developed.

Surely to get the best experience you would want to use the best tyre technology affordable and if 'vintage' tyres are using old tread patterns (rubber compounds?) can that be considered best practice?

My thoughts exactly. Tyres are so much like baby products - "surely you want the best for your child?". There is benefit (safety) in quality, but what does that mean in practice? I would love to see a side-by side comparison of tyres with different specs on a TR6. For example, modern 185/70/R15 "white van" tyres, vs super expensive 185/70/R15 "period" tyres, vs a tyre with a (for example) 55 profile on the appropriate rim to give the correct rolling radius and fill the wheel arch. I wonder if the white van tyre with current composition and tread technology might be much better than we purist /period correct snobs (me included) expect...
JC

[stuart]

44 minutes ago, JohnC said:

My thoughts exactly. Tyres are so much like baby products - "surely you want the best for your child?". There is benefit (safety) in quality, but what does that mean in practice? I would love to see a side-by side comparison of tyres with different specs on a TR6. For example, modern 185/70/R15 "white van" tyres, vs super expensive 185/70/R15 "period" tyres, vs a tyre with a (for example) 55 profile on the appropriate rim to give the correct rolling radius and fill the wheel arch. I wonder if the white van tyre with current composition and tread technology might be much better than we purist /period correct snobs (me included) expect...
JC

Van tyres normally have a lot stiffer sidewalls to cope with weight carrying capabilities plus the speed rating is usually a lot lower.

Stuart.

[dougal]

On 11/12/2024 at 6:33 PM, jerrytr5 said:

Having read the Longstone article, I think that there is a degree of economy with the truth going on.

I refer to the statement "Some TR6 owners install 185/70R15 or 195/65R15 tires. We believe that if bigger tires enhanced the TR6's driving abilities, Triumph would have installed them as standard."

I recall in the late '70's early '80's it was almost impossible to get 15 inch tyres as almost all cars of the period ran on 13 inch. I don't know when profiles lower than 80% were introduced but when the TR6 was in production I suspect the only car using 70 profile with a 15 inch rim would have been the XJ6 on 205/70, which I did have to resort to on my 4A as nothing else was available/affordable for the average driver (perfectly safe on those narrow rims, Officer).

To suggest that BL might have re-assessed the tyre on an outgoing model does not seem realistic to me particularly as 70% profile was in it's infancy and 65% not yet developed.

Surely to get the best experience you would want to use the best tyre technology affordable and if 'vintage' tyres are using old tread patterns (rubber compounds?) can that be considered best practice?

Jerry

nearly all wrong.

Yes 13" was comon on Spitfires and Ford and Vauxhall, etc, but 15" 70 profile tyres were comon place in the 1970s. Porsche, Volvo, Maserati, Citroen, Aston Martin, Rolls Royce, Jensen, Bentley, Lamborghini, Cadilac, De Thomaso. But really, to be more precise; 185/70R15 tyres were comon place since 1968 because it wasn't only De Thomaso that fitted them, it was Volvo and Porsce fitted it as OE. However it was a comon size, because as well as those car manufacturers that set there cars up to sduit these tyres cars like TVR, MG and swathes of TR's that fitted 165R15 fitted 185/70R15 as a misguided up grade. However in those days they were at lease putting tyres on that were designed to be used in that enviroment; presesnted to the road at that much of a variable angle.

lower than  70% profile was developed in 1971. (Lamborghini Miura SV 1971, Porsche RS 1972 from memory i think there was a Lotus in there as well.)

the best experience is the best carcass that suits your car, with the best build quality, and modern improved compounds that are better in the wet. looking good is a bonus.

I understand not wanting to spend the money. But it should be accepted why the determination is there to buy a cheaper tyre it is because of the price; but these high quality performance period tyres are better as a road tyre on your old car geometry and suspension.

 

look it is all on were. 2 different back to back tyre tests against totally modern tyres that have benefitted from all that clever computer modeling. by your theory they should be better but they aren't. Pirelli knocks all these modern tyres into a cocked hat, because a period tyre works vbetter on a classic car, and they are top quality.

https://www.longstone.com/classic-tire-test 

 

[Adrian Steele]

 Dunlop Sport BluResponse 195/65 R15 H (91) are a really good choice. Look good and drive well.

Gave had them for 3 years now and very pleased with them. 

[dougal]

19 hours ago, Adrian Steele said:

 Dunlop Sport BluResponse 195/65 R15 H (91) are a really good choice. Look good and drive well.

Gave had them for 3 years now and very pleased with them. 

Hmm

sorry; they are not a good choice for a TR. They have completely wrong structure and size. They are designed to operate in a completely different enviroment than that provided by a TR6. it is like trying to play a CD in a record player.

[Mike C]

23 hours ago, Adrian Steele said:

 Dunlop Sport BluResponse 195/65 R15 H (91) are a really good choice. Look good and drive well.

Gave had them for 3 years now and very pleased with them. 

I'm also very pleased with my P6 Pirelli's in this size , mine are now seven years old and will be due for replacement soon even though they are only slightly worn. Whatever tyres are fitted to a TR6 most will age expire long before they are worn out-that's why I stick to a common , mass produced tyre- they're cheap and fresh from the factory

But then TR6 tyre selection is a personal preference, select whatever you believe works best for your car- a bit like gearbox oil.

[Adrian Steele]

On 11/19/2024 at 4:59 PM, dougal said:

Hmm

sorry; they are not a good choice for a TR. They have completely wrong structure and size. They are designed to operate in a completely different enviroment than that provided by a TR6. it is like trying to play a CD in a record player.

Funny, but 10k miles suggests they are really a very good choice. Agreed if you want factory a standard car they aren’t right - but I’m guessing a lot of us aren’t running factory standard cars anymore. 

[Tom Fremont]

On 11/19/2024 at 11:59 AM, dougal said:

Hmm

sorry; they are not a good choice for a TR. They have completely wrong structure and size. They are designed to operate in a completely different enviroment than that provided by a TR6. it is like trying to play a CD in a record player.

I ran a set of 195/65s in Michelin Pilot Exalto on my [ triple Webered CP spec ] TR250 for over 43,000 miles. Do they work? Yes. Do they have the best grip? No. Do they have the meaty appearance favored by U.S. TR6 owners [ with their under powered emissions engines mostly ]? Yes. But they don't even touch the pavement 1/2" in from the edges at 25 psi and their diameter is less than that of the 165-15s fitted to cars with the 3.45:1 differential ( I've got in that one ).

Since I have 6" Panasport wheels 165s are too narrow. I wound up with Michelin 185/70 XWX and am on my second set; first was good for about 25K miles, a disappointment but they're fine otherwise. They don't have the grip of the NLA 185-15 XAS which I had until about 14 years ago and I doubt anything else does either. Both sing a charming tune at 30+ mph and the iconic look can't be beat. Hope that choice doesn't incur the wrath of Dougal 

 

[dougal]

Ha ha! No Tom, XWX are very much a suitable carcass for your chassis. (though i might personally have unofficially stretched a 165R15 on a 6" rim. or on a US model i might have stretched a 180HR15 XAS for the longer legs. https://www.longstonetyres.co.uk/michelin-classic-tyres/xas.html ) The XWX are great tyres for your cars https://www.longstonetyres.co.uk/michelin-classic-tyres/xwx.html i sell loads of XWX to some very exotic cars from that period.

 

Adrian Steele 

You might not have factory settings, but a modern cars suspension is incredibly different; in the way it presents a tyre to the road. All you can do is lower and stiffen and change your camber to try to keep your footprint on the road in the corners while sacrificing other characteristics like wear and ride . It is worlds apart from a modern car they have caster and the camber changes as the car leans.

[JohnC]

On 11/20/2024 at 3:59 AM, dougal said:

it is like trying to play a CD in a record player.

I'm sorry Dougal, but that's not helpful. CDs are digital; record players are analogue. One is blue; the other is hard (or smelly, or quiet, or ...). Having said that, I believe you know what you're talking about. Is there a book or similar that those of us who have enough time and interest (aka we're old) can read? I, for one, am interested in the way tyre and suspension design have evolved. And I'd like to be able to make an informed decision about what tyres to use. Particularly when there's such a price difference between the choices. Perhaps I would prefer to modify my suspension once (concours judges cover your eyes) rather than pay more per year for tyres?
JC

[dougal]

Changing your suspension to suit derive more grip from a modern car just means compromising your ride, in that you stiffen and lower it. You then add adverse camber which will mean that when driving in a straight line you are riding on the inboard edge of your tyre. modern cars suspension and steering is dramatiaclly different to yours. you just need to buy a record instead of a CD. It depends what you are prepared to compromise.

[John Morrison]

On 12/6/2024 at 12:10 PM, JohnC said:

I'm sorry Dougal, but that's not helpful. CDs are digital; record players are analogue. One is blue; the other is hard (or smelly, or quiet, or ...). Having said that, I believe you know what you're talking about. Is there a book or similar that those of us who have enough time and interest (aka we're old) can read? I, for one, am interested in the way tyre and suspension design have evolved. And I'd like to be able to make an informed decision about what tyres to use. Particularly when there's such a price difference between the choices. Perhaps I would prefer to modify my suspension once (concours judges cover your eyes) rather than pay more per year for tyres?
JC

Hi John, 

on cars of our era, tyres were, ball park, 50% of the suspebsion, by design, just look at the height of the sidewall.

Moderns, even non exotic moderns are nothing like that, just look at the sidewall, 

you can't compare apples and pears.

I run 165 x 15 (80% aspect ratio) and happen to buy Michelin XAS, have done for 30 years plus now.

I've heard it said 'Good, but eye wateringly expensive, milage I do I'll never wear them out'' - well really, guess you pays your money and takes your choice, but

tyres are the only thing between you and the road, they transmit everything, and I prefer to be confident that I don't need to think about them.

To visit your original post, they happen to be 'Period correct' XAS that is, as well as 165 x 15, over the years I've seen some absolute horrer fitments, in the name of improving cornering, wet grip etc. I've also learned, as have others, sometimes the hard way, that Triumph knew what they were doing, and there is a mountain, of 'Fixing stuff, that ain't broke'

Whatever you do fit, look after them, Especially, pressures.

John.

[Dag]

I have an ex U.S. 1969 TR6 (3.7 ratio diff), which I purchased with 195/65R15 tyres.  Not a good match in my opinion; heavy steering, incorrect speedo and high RPM when cruising - even with overdrive.

I changed to Michelin XAS 180/80R15 in 2023 which completely transformed the car.  With the XAS the car feels more agile.  It is easier to drive with lighter steering.  It goes dead straight when cruising.  The speedo is correct, and the RPMs have gone significantly down.  I'm very happy and will never go back to the wider, low profile. 

[John Morrison]

Welcome to our forum, Dag.

John.

[Dag]

Thanks. I love the forum.

Dag

[dougal]

On 12/10/2024 at 10:16 AM, John Morrison said:

Hi John, 

on cars of our era, tyres were, ball park, 50% of the suspebsion, by design, just look at the height of the sidewall.

Moderns, even non exotic moderns are nothing like that, just look at the sidewall, 

you can't compare apples and pears.

I run 165 x 15 (80% aspect ratio) and happen to buy Michelin XAS, have done for 30 years plus now.

I've heard it said 'Good, but eye wateringly expensive, milage I do I'll never wear them out'' - well really, guess you pays your money and takes your choice, but

tyres are the only thing between you and the road, they transmit everything, and I prefer to be confident that I don't need to think about them.

To visit your original post, they happen to be 'Period correct' XAS that is, as well as 165 x 15, over the years I've seen some absolute horrer fitments, in the name of improving cornering, wet grip etc. I've also learned, as have others, sometimes the hard way, that Triumph knew what they were doing, and there is a mountain, of 'Fixing stuff, that ain't broke'

Whatever you do fit, look after them, Especially, pressures.

John.

 

Well said John. Nicely said. the XAS are a great choice. In fact I beleive Triumph agreed with you as well, in i beleive the TR6 fitted 165R15 XAS. we have been shipping the XAS all over the world for some time now. they are definitely great tyres i have had them on several cars and raced a fast Cortina on them.

https://www.longstonetyres.co.uk/michelin-classic-tyres/xas.html

The Cinturato is, sort of, a new tyre on the market and one that Pirelli started making again recently, but again last decade. Like the XAS they were the best tyres around in period for these cars, and the new productions maintain all that benefit of having the right carcass but with modern build quality and modern compounds that are just so good in the wet. the fact is we are in good order for 165R15 tyres.

https://staging.longstonetyres.co.uk/tyres/165-15.html

On 12/10/2024 at 10:52 AM, Dag said:

I have an ex U.S. 1969 TR6 (3.7 ratio diff), which I purchased with 195/65R15 tyres.  Not a good match in my opinion; heavy steering, incorrect speedo and high RPM when cruising - even with overdrive.

I changed to Michelin XAS 180/80R15 in 2023 which completely transformed the car.  With the XAS the car feels more agile.  It is easier to drive with lighter steering.  It goes dead straight when cruising.  The speedo is correct, and the RPMs have gone significantly down.  I'm very happy and will never go back to the wider, low profile. 

 

Yep a 195/65 R15 tyre will have a totally unsuitable cacass design for a TR and any of the modifications you do to try to derive extra grip by keeping the foot print on the tarmac while cornering, just goes toward making it a less pleasant road car.

 

yep the 180HR15 Michelin XAS is a great option for the US cars where they like a bit more diameter. they are similar in width to a 165 while they are just a bit taller to try and keep your exhaust pipe on when you drive over all these horrible speed bumps.

 https://www.longstonetyres.co.uk/michelin-classic/xas/180-hr-15-michelin-xas.html

 

[DRD]

22 hours ago, dougal said:

 

The Cinturato is, sort of, a new tyre on the market and one that Pirelli started making again recently, but again last decade. Like the XAS they were the best tyres around in period for these cars, and the new productions maintain all that benefit of having the right carcass but with modern build quality and modern compounds that are just so good in the wet. the fact is we are in good order for 165R15 tyres.

https://staging.longstonetyres.co.uk/tyres/165-15.html

 

I've just got hold of a set of Cinturato 185R15 tyres and am looking forwards to trying them out on my ex US car.

[dougal]

Please let us know how you get on. 

if you are going to fit a 185R15 on a TR6 Then the Cinturato CA67 is the best suited.

https://www.longstonetyres.co.uk/tyres/185-15/185-vr-15-pirelli-cinturato-ca67.html 

And these sets are a bargain

[DRD]

3 minutes ago, dougal said:

Please let us know how you get on. 

if you are going to fit a 185R15 on a TR6 Then the Cinturato CA67 is the best suited.

https://www.longstonetyres.co.uk/tyres/185-15/185-vr-15-pirelli-cinturato-ca67.html 

And these sets are a bargain

Yes this is what I've now got.

First impressions are very good, although I haven't pushed it yet.

What has surprised me is the ride is much better, and as expected the steering lighter as well.

[DIYBOSSCAT]

On 11/14/2024 at 12:02 PM, JohnC said:

My thoughts exactly. Tyres are so much like baby products - "surely you want the best for your child?". There is benefit (safety) in quality, but what does that mean in practice? I would love to see a side-by side comparison of tyres with different specs on a TR6. For example, modern 185/70/R15 "white van" tyres, vs super expensive 185/70/R15 "period" tyres, vs a tyre with a (for example) 55 profile on the appropriate rim to give the correct rolling radius and fill the wheel arch. I wonder if the white van tyre with current composition and tread technology might be much better than we purist /period correct snobs (me included) expect...
JC

Hi John, 

There is a Osprey Restoration Guide book on "How to restore Suspension and  Steering" by Roy Berry.   ISBN 0-85045-715-7

Whether you can still get a copy or not or if its what you are looking for, as it was published in 1987.

Vince

[dougal]

On 12/18/2024 at 12:28 PM, DRD said:

Yes this is what I've now got.

First impressions are very good, although I haven't pushed it yet.

What has surprised me is the ride is much better, and as expected the steering lighter as well.

What are you comparing them to? what was on before?

 

i must say everyone we sell these tyres to is always happy with them. once you have recovered from your credit card bill they are brilliant, they will be fitted to your car long after you have recovered from that, specially with the really special price we currently have on a set of these tyres

https://www.longstonetyres.co.uk/185-vr-15-pirelli-cinturato-ca67.html

 

[jimt]

On 12/12/2024 at 1:35 PM, DRD said:

I've just got hold of a set of Cinturato 185R15 tyres and am looking forwards to trying them out on my ex US car.

On the USA cars was the suspension set up or spring ratings any different to the U.K. spec cars? 

[DRD]

2 hours ago, jimt said:

On the USA cars was the suspension set up or spring ratings any different to the U.K. spec cars? 

Not as far as I'm aware!

[Trumpy]

Did the Tr6 come with Michelin tyres as standard ?  I ask as a picture taken of my car when it was new appears to show crossplys.  Admittedly it’s a Tr5 so a year or two older ( yeh, i know I’m in the wrong forum  ) but I’m surprised Triumph supplied their new 150hp roadster on poor tyres . 
It had worn but Michelin XAS on when I bought it but being on a tight budget I replaced them with much cheaper Dimax classic 185/70 s . They have period looks and shape  and four years in are performing well . 
pics to show old and new 

 

[Keith Warren]

As I understand the TR6 could have had either Dunlop SP Sports or the XAS tyres my Heritage Certificate from a CP 1972 stated Dunlop.

Keith