Observations on my tyres

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Observations on my tyres

2668GRIFFIN

''LUIGI''
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Thats it..my OCD has just kicked in
I just could not have two different makes of tyre
So why?
If you bought a brand new car would you not complain if there were different tyres on it?
Luigi
 

chris3234

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Thats it..my OCD has just kicked in
I just could not have two different makes of tyre
So why?
If you bought a brand new car would you not complain if there were different tyres on it?
Luigi

Who said anything about it being brand New?
And most cars more then a few years old on the road will have different tyres I try to have the same accross an axle but wouldn't think twice about having two pair of different tyres front and rear
 
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Who said anything about it being brand New?
And most cars more then a few years old on the road will have different tyres I try to have the same accross an axle but wouldn't think twice about having two pair of different tyres front and rear

This is one of the reasons that tyre manufacturers compete strongly for contracts to supply production lines, as many will stick with the same tyre throughout their ownership. Nothing wrong with that, if you have the budget, and supply is acceptable.

All tyre manufacturers update their specifications regularly, and usually change the sesing of tread patteern and sidewall markings for each new version. Maintaining the same tyre for several years can therefore be difficult or impossible, and the next generation tyre can be as different in performance and feel as another brand. So your OCD might get a bit of a workout there, unless you wish to stretch the budget and buy a full set every time. (Necessary on many 4wd systems, as they cannot handle minor rolling diameter differences well.)

My choices are based on budget, and availability. When I put the Firestones on the front, all four were old Continentals. Impossible to match, as Conti were by then two generations on, and very expensive at the time. They were also a bit harsh in ride, and not particularly grippy in the wet.
Later when the rears needed replacement, Firestone were difficult to find, and these Semperit were available, and a comparable price. alternatively I could have just not used the car for a week or so, waiting for Firestones.

The Fabia, a working car, with learners, who try to attack kerbs, needs a good brand, but without breaking the bank each mishap. The original Goodyears are expensive, and not particularly good. I've had experience with Tigar, and they were available at a good price, and seem to suit the car well, so have two of those on the rear, and the spare. Supply is generally good, so the fronts will be the same sometime soon.

Mixing across axles is not desirable, some fight, others seem fine, but you won't know until after you've spent the money of course, but for the reasons above, even the same brand across an axle may be different. With 'normal' driving, few will ever notice anyway. Higher performance cars matter more. I don't think either of my cars fit that category.
 

StevenRB45

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As long as it's not the cardinal sin of 4 budget tyres of varying ages..nothing screams car that's been maintained with sellotape and chewing gum louder.

If I lost a tyre to a puncture I'd have to go mismatched currently Goodyear Vector 4Seasons gen 2 have been replaced by Gen3 in my size now.

Will say I was vaguely furious when I picked my current car up. When I test drove it had 4 matched factory toyos on it at 36k miles which spoke of it having had a reasonably easy life up to that point. They were beyond their best with 3.5 on the rear and 4.5 on the front so had been rotated. I mentally put it on my list of things to sort in next 6 months or so and got on.

Pick up day comes, "Good news we've put 2 new tyres on it for you" and they had indeed I now had two Landfill ls388s instead of my nice matched set. Oddly enough they went in the bin barely worn.
 
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...
Pick up day comes, "Good news we've put 2 new tyres on it for you" and they had indeed I now had two Landfill ls388s instead of my nice matched set. Oddly enough they went in the bin barely worn.

I had a tyre shop in Swindon do something similar to me many years ago. I was running a Fiat Argenta, used to eat front tyres. An unpopular size, so choice was poor. Was good on Firestone, very good on Goodyear, but they were expensive, so had to get them when on offer.
Tyre shop in Swindon had offers on, confirmed that they had two Goodyears of my size in stock, so booked an appointment. Despite the appointment, they were busy, and would take 40 minutes, so I wandered off. When I returned, they proudly announced that they only had one in stock, so had fitted two cheap ones instead. No offer of cheaper price, but that was irrelevant, as I was not having them. They were a bit miffed when I told them they'd have to refit my old ones, on the correct wheels, and the correct orientation, and balance them, which they did. It is a carpet shop now.
 
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Pugglt Auld Jock
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I suppose they thought they were being helpful, and a lot of people would, probably, be happy enough - not me though! One fundamental I learned early on was that you do nothing to a customer's vehicle without first getting their agreement and then don't do anything which inflates the price by more than a smidgeon without getting the go ahead.
 

StevenRB45

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They were a bit miffed when I told them they'd have to refit my old ones, on the correct wheels, and the correct orientation, and balance them, which they did. It is a carpet shop now.

As I'd not paid for them at all...I wasn't going to ask them to dumpster dive for some 70% worn Toyos.

Nearly had cause to regret that decision as due to now having 4.5mm on the front and 8mm on the rear new tyre purchase was delayed.

Until one morning I entered a corner I've done a 1000 times and have done 1000 times since on a slightly wet cold morning. Little late for work so carried maybe 1 or 2 mph more than usual but not excessive, or so I thought.

The old toyos on the front just didn't bite and I was on a straight line for a lamp post on the corner exit, then when they did bite that overwhelmed the available grip from the Landfills. So went from terminal understeer to snap oversteer in about 2-3 seconds. Thankfully I was only doing 30 mph or there abouts so got it gathered up and continued.

Booked it in for 4 new boots that day and it's never surprised me since.
 
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Pugglt Auld Jock
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Well done on the car control Steven. Inducing oversteer deliberately in the "right" circumstances - closed circuit or skid pan come to mind - is highly entertaining and can teach you a lot about car control but when it happens in circumstances such as you mention above I think most people would be caught out and recovering control is more a matter of good luck than skill. My perception is that most people, once the tyres loose adhesion, have very little idea what to do and even less idea how to put theory into practice. I remember vividly an incident when a young passenger with my mum in Dad's Mk2 3.8 Jag (his "special" toy) when we hit what I now think was probably black ice on a country road near home in the Borders and it became obvious the car was just going where it wanted! She took her hands off the steering wheel altogether! I couldn't wait to be able to drive when young so I already had a good idea of what driving was all about and I knew it didn't involve letting go of the wheel! I later asked her about it and she said, Cars have a lot in common with horses you know (she was a keen horsewoman, riding with the hunt etc - which I hated her doing) and when a horse looses it's footing the best thing you can do is slacken the reins and allow it to have it's head. Yes but -------, I said. Well it all worked out didn't it? she said, We didn't crash did we? I gave up at that.
 

DaveMcT

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The General (brand) tyres on my 100HP are getting near to end of life. At £50 each the price is very fair. They are not especially noisy and cope well in wet weather. Aquaplaning happens in heavy storm rains but the Bridgestone Potenzas on the Audi were much the same. By the way the fancy Goodyears I fitted when the Potenzas wore out were horrible -noisy harsh ride - yuk.
Back to the 100HP, Generals will be my first choice when they are due. Saying that Black Circles has Avons at £50 so will see what my local tyre guy can offer. He's is usually the best price fitted.
 
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StevenRB45

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Well done on the car control Steven. Inducing oversteer deliberately in the "right" circumstances - closed circuit or skid pan come to mind - is highly entertaining and can teach you a lot about car control but when it happens in circumstances such as you mention above I think most people would be caught out and recovering control is more a matter of good luck than skill. My perception is that most people, once the tyres loose adhesion, have very little idea what to do and even less idea how to put theory into practice.

I spent a lot of time sliding about in my formative years. There's definitely a difference between pedalling a kart, or a rally car or a grass track buggy full belt provoking a 4 wheel drift or over steer slide knowing you've got a bit of space to play with or at least a helmet and a full cage if it goes wrong and the situation just arising out of nowhere.

While I'd love to say it was extreme helmsmanship that saved the day, from the exterior it was probably deeply undramatic to watch. Scarier from the drivers seat than exterior I'd imagine but obviously you know what you've requested and the reaction you are experiencing so it tends to widen the eyes when you get something else. Only time the very hands off DSC system has intervened in anything not wheelspin or ice related. It jammed a rear brake on shortly after I'd got it straight, expect it was expecting an over correction and was doing so to pull it straight.

I feel like you've mentioned your mam doing this before, she's actually using an advanced drifting technique...if you can't get enough lock on fast enough release the wheel and it'll find it's happy place. Obviously in a drift car that has a specialised suspension steering set up and 90 degrees of lock available...:ROFLMAO:
 
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For many years I participated in autotests, slinging a car through coned routes on an airfield. Much of this was in a Triumph Stag automatic, possibly one of the least suitable cars, as understeer was easily induced. Dad, who's car it was (we still have it, but not used since mid eighties, anyone fancy a restoration project?), kept a set of spare wheels, not for winter tyres, but for the old worn out ones for such events. With some of the tight turns, it was possible to overwhelm the steering pump, making the steering very heavy. Taught me a lot about understeer and oversteer, which was useful when trying to pilot Mum's Mk2 Cortina, and later my Marinas in snow and ice.

Here's one for Jock, the DAF 66, with its nearly 50/50 weight distribution would grip tenaciously, but then let go with all four at once. Quite exciting. I've always puzzled when journalists wax lyrical about 50/50 being so good, give me predictable under or oversteer every time. The Argenta could be provoked easily into oversteer on wet roundabouts, but very easy to control, lots of fun.
 
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Pugglt Auld Jock
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For many years I participated in autotests, slinging a car through coned routes on an airfield. Much of this was in a Triumph Stag automatic, possibly one of the least suitable cars, as understeer was easily induced. Dad, who's car it was (we still have it, but not used since mid eighties, anyone fancy a restoration project?), kept a set of spare wheels, not for winter tyres, but for the old worn out ones for such events. With some of the tight turns, it was possible to overwhelm the steering pump, making the steering very heavy. Taught me a lot about understeer and oversteer, which was useful when trying to pilot Mum's Mk2 Cortina, and later my Marinas in snow and ice.

Here's one for Jock, the DAF 66, with its nearly 50/50 weight distribution would grip tenaciously, but then let go with all four at once. Quite exciting. I've always puzzled when journalists wax lyrical about 50/50 being so good, give me predictable under or oversteer every time. The Argenta could be provoked easily into oversteer on wet roundabouts, but very easy to control, lots of fun.

Wow PB, autotesting in an automatic stag? As you say, has to be one of the most unlikely cars I could think of for this activity but I'd have come to watch you just to hear the lovely exhaust burble! Was it a Borg Warner auto box? actually, no matter what make I can't think of a much tougher way to use one - did it give a lot of trouble? For anyone who's never seen auto testing take a look at this. https://www.youtube.com/watch?v=QpoIs9iPHoM If you get a chance do go along to a live one, it's crazy stuff and, as you can see, some very interesting and specialized machinery to be viewed.

Marinas, like their earlier relatives the Minor, were "horrible" in slippy conditions, mainly, in my opinion, because they had no weight in the rear and were, of course, rear wheel drive. I can remember on one occasion actually getting out of a Minor on an icy brae, with it still in first gear and the engine ticking over, to watch the O/S rear wheel slowly rotating on the ice with no sign of forward movement of the vehicle at all!

I never drove a 66 in a "spirited manner" but I did have a few very entertaining moments in the boss's 55 Marathon with it's swing axle rear end! luckily the relatively skinny tyres brought on the "excitement" long before I terminally lost control - which would no doubt have resulted in a loss of employment also! Here's a clip of a 55 marathon being very capably hurled about: https://www.youtube.com/watch?v=jXRKsxrlNCA watch the rear wheels and you can see the "odd" angles of attack induced by the swing axle. The worst thing you can ever do when cornering fast in a vehicle with swing axle rear suspension is to lift off the throttle - almost guaranteed to induce an uncontrollable spin!
 
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Wow PB, autotesting in an automatic stag? As you say, has to be one of the most unlikely cars I could think of for this activity but I'd have come to watch you just to hear the lovely exhaust burble! Was it a Borg Warner auto box? actually, no matter what make I can't think of a much tougher way to use one - did it give a lot of trouble?

The autobox never gave trouble. Borg Warner type 35. Was just prior to them upgrading to the type 65. For autotests, Dad had taken a file to the selector gate, so only needed sideways movement for P, all other positions were straight back/forward. This gave a simple pull, all the way back for 1, and all the way forward for R. When we ran out of room on an autotest, the lever was pushed, car went back, shift again and forward. Very quick. Drive with one hand on the steering, one on the selector, and one foot on each pedal. Brutal. I've still got a few trophies here somewhere.

Club Triumph, the umbrella of all Triumph clubs, run a 'round Britain' event every two years. We did this in the Stag, 1984, still have the Barclaycard receipts for the fuel, strange souvenir. And a commemorative tankard too.
The run starts from North London, teatime Friday, arrives John O'Groats for breakfast Saturday, Land's End for breakfast Sunday, then back to North London, arriving teatime.
Dad had driven from Bristol to Portland, and I'd driven from there to North London, so a faie few miles before the 'start'. And of course, the return afterwards. I got to bed around midnight, Dad a couple of hours later. I remember waking up around midday Monday. (Had taken the day off.)

After breakfast Saturday, having neither of us slept since Friday night, we stopped for a nap. Slept for over an hour, so were behind schedule. There's a B road on the south side of Loch Ness, around 35-40 miles. We did that in just over 30 minutes. Not a pampered car.

Had a track day at Castle Combe too with the Triumph Club. With me driving, I was third fastest. Against tuned Spitfires, TR6s and TR7s. Only faster were a proper race prepped TR6 and a race prepped TR8, and I nearly caught him, but the temp sensor on the autobox showed hot, so had to pull off for it to cool.
Same day, brother was using a 1200cc Herald. Not quick, but an unusual technique. Flat out in top gear, everywhere. As he entered each corner, the outer rear wheel tucked under, scrubbing speed. Hilarious to watch, but still slowest of the day.

Did a production car trial too, in a steep field just south of Bristol. Somewhere there was a photo of me cresting a steep climb, with both front wheels off the ground momentarily.
 

DaveMcT

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Everything from around that age suffers with rot so whoever take your Stag will need some bodywork skills. It was heavily criticised for cooling problems and many were fitted with a Rover V8. The fix was a thicker radiator and today you could consider a waterless coolant. But PB knows all that without me wittering on.
 
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Everything from around that age suffers with rot so whoever take your Stag will need some bodywork skills. It was heavily criticised for cooling problems and many were fitted with a Rover V8. The fix was a thicker radiator and today you could consider a waterless coolant. But PB knows all that without me wittering on.

My father put a lot of thought into the cooling issues. A thicker core radiator is only addressing the effect, not the cause.

He realised that the auto gearbox filled the tunnel, with very little clearance. This is where air drawn in through the radiator needs to go, to exit at the back bumper, as the air under the car is high pressure when moving. with only a small gap, airflow might be insufficient.

On a dry day, he placed a couple of old oily rags under the bonnet, and set fire to them. They smoulder slowly, and give off lots of smoke. With the roof off, he drove away, with him and brother lookiing for the exiting smoke. There was none. Brother laid over the rear deck/bootlid, but none exiting from the rear.

He found that the air through the radiator, exits forward past the headlamps, to be drawn in through the radiator again. Not much cooling effect from that.

Next stage was to stick bits of wool over the car to determine airflow, particularly around the bonnet and front wings. The bonnet does not reach the front of the car, there being a short deck in front of it. He found the front edge of the bonnet, maybe 4-5" from the front of the car, had the wool standing straight up. So a low pressure area there. Aerodynamics of the car, poor. So he cut two slots each side at that point, relit the rags and off for another test drive. Two lovely plumes of smoke each side, rising about 6" before dissipating. He also added a plate beside each headlamp to prevent the air escaping that way.

If you've ploughed through my story above, you'll know the car led a hard life, lots of amateur motorsport events, a session around Castle Combe racetrack, and driven briskly on the road. No more overheating. Standard radiator.

Another issue is the V engine. Block, heads and manifold are all alloy, but different, forming a triangle, and as they heat up, are pushing against each other. The manifold gaskets get a hard job keeping coolant in with this expansion/contraction, and generally last only around 24,000 miles, so became a service item to replace every 12,000. Coolant leaks into the inlet manifold, drawn into the cylinder, to be expelled throught the exhaust, or dropped into the sump, diluting the oil. Oil pressure is low on these, diluted oil is not good, and the crank bearings have a short life as a result.

He bought the car with 35k on the clock, already with a replacement engine. He reshelled the bottom end and resealed the manifold at around 50k, at which point he performed his cooling mods. Last used at around 140k, needs another engine rebuild, as oil pressure was almost zero again.

Structurally, I think it needs sills, and the front wings are a bit frilly at the wheelarches and rear edge.
 
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Pugglt Auld Jock
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Here's an interesting site for you PB. https://www.favershamclassics.co.uk/engines Bears out what you were saying about the inlet manifold problems.

We never really had anything to do with the Stag, but their cooling problems were legendary. Maybe once in a blue moon you'd see one for a service, but there were a lot of 1850 Dolomites. I seem to remember the plugs weren't too accessible due to the slant on the engine installation but mostly what I remember was one which I got the job of taking the head off. Everything corroded to a ridiculous degree! Glad I've never had to do another.
 

DaveMcT

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PB. Thats a very interesting tale about the poor cooling airflow. You can see why Jags and Land Rovers have exit louvres at the back of the front wings.
 
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StevenRB45

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PB. Thats a very interesting tale about the poor cooling airflow. You can see why Jags and Land Rovers have exit louvres at the back of the front wings.

If memory serves on a land-rover they are an intake (or at least one of them is.)

Both makes it easier to fit a snorkel and less likely to drown while fording, other is probably a blank for symmetry.
 

s130

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It has long been recommended that caravan and trailer owners replace their tyres every 5 years regardless of mileage.

I can see some of logic in this:

o wheels parked up and stationary and loaded for lengths of time without rotation
o often (coupled with the above) left open to UV degradation etc.

Another problem with trailed units is that any tyre issues (short of a rapid blowout) take their time to be detectable in the towing vehicle.

The point I'm making is that the caravan/trailer industry recommend tyre replacement every n years. I've never seen this/similar in the motor car industry. Here the rules/requirements are legal minimum tread depth and visible damage/deterioration.

So no person is allowed to travel in a trailed unit (the law) which has recommended tyre replacement every 5 years but people can travel in cars with very old tyres that may have internal etc. issues due to age.

Both approaches/perspectives make an interesting debating point. :)

Have fun!
 
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