Road handling behaviour transformed

[iRS]

I've just put my winter tyres on and I am astonished by the difference. I'm sure this is nothing to do with the tyres being winter ones, but everything to do with going from 19" to 18" and from what I believe are original spec Pirellis to another brand.

I got the wheels and tyres last winter locally in Aberdeen. The seller had bought them all together from the dealer sometime before (at no doubt top price). I got them at a very good price mainly because the alloys were so badly kerb damaged. The wheels are off an XF and the tyres are Nokian.

This year ahead of fitting them, I repaired the damage with body filler and painted them black with a bit of paint I had lying around. The front ones are painted with POR15 and the rear ones with some old black enamel, I think the brand is repaint.

Once I drove the car with the winter tyres on I suddenly became aware just how quiet the car was and then did remember that the noise increased when I put the 19" ones in the spring. Now I can just hear the aged supercharger and a bit of whine from the gearbox in lower gears.

But not only that, the road holding has been transformed. Gone has the pulling to one side according to camber, tracking road contours, gripping white lines and general jitteriness. Now it just goes where its supposed to. I have spent an age tweaking camber, tracking and caster, but all pointless when it would seem it was the tyres causing the problem. The question now is what to do in the spring. I certainly shan't be putting the Pirellis back on, but do I trust spending a few hundred quid on 19" tyres in the hope it was the tyre brand itself and not a function of wheel size or should I stick with 18" wheels and suitable tyres?

[J44EAG]

Interesting, Roger.

Our Uncle Rob maintains that best comfort and ride are on 19". From my own experience, 20" rims will always give a less compliant ride with more general suspension NVH being transfered to the body structure. Remember old tyres can develop a "set" depending on their running location. I`ve experienced a couple of elderly tyres that would pull the front of the car in one direction despite copious camber, toe and caster corrections. To cure the issue, I fitted new tyres on the front having checked rims were not buckled. I then finished the old carcasses off on the rear wheels just to get as much value from them as possible.

I moved away from Pirelli many years ago. Noisey, skittish when worn, tendancy to understeer even at slow speed, just not my kind of tyre. Dunlop Mxxx are a revelation by comparison. Avon ZZ5 I like very much but wear rates are rather high. They do however stay sharp to the bottom of the glass and they are a very grippy tyre.

I started today with a deflated NSR tyre. Puffed it up and went to my now local tyre man near Caterham in Surrey. Given a coffee, I sat there waiting for the repair to be done. In came John from the tyrebay..."Come and have a look please, Mike". One ZZ5 with a nail right on the turn of the carcass, a bulge on a well worn NSF tyre, another ZZ5 nearly down on the blocks and the last tyre ok but again not far off the block limit. Four new boots needed. So it appears because I use my car hard, I`ve managed to wear out the ZZ5`s in 15k miles. I can`t say I`m suprised. I do use this car quite brutally at times. That is why I bought it....

The tyre company MD, Mark, suggested his top budget tyre. I was initially sceptical until John showed me his Porshe shod with a set of Jinyu YU63 boots. He said he was more than happy with them. I needed four new, reliable tyres at a reasonable figure. Wet grip is slightly down compared to the Avon ZZ5. So these new tyres have 97Y rating, Class C1, Fuel C, Wet grip C, Noise DB70, Noise 2. Cost £100 each fitted with VAT. It could have been a £630 invoice instead of the £400 had I gone ZZ5 or Mxxx again.

In perspective and bearing in mind my own typically high rear tyre consumption and very hard everyday use, I found it hard to justify spending an extra £230 going for the upmarket "well badged" Avon or Dunlop option when these new Jinyu boots will probably suit my needs well enough. Being LP 35% tyres, damage is easily done. On 20" rims, regular tyre damage can be a frequent occurance and no doubt a couple of these new tyres will get hit before they are worn out. A £100 per unit write off is more acceptable than £150. After fitting I needed to spin the rear wheels up a couple of times to achieve some grip with the new tyres on our wet, greasey, slippery November roads. That done, rear grip seems to be coming on line after thirty miles or so.

Tonight I`m glad to get a fully matched set of tyres on this car. I knew I`d have to replace a couple of them before the MOT in February. This tyre change happened just a bit faster than I anticipated. No moans though because I now have a fresh set of rubbers for the winter even not though winter tyres. I think I can live with that.

For those near to Caterham needing tyres, I heartily recommend Tyremark. Mention myself and the JEC to get a reasonable deal from MD Mark Webber or his Manager Anthony Hazel. All there are top guys and are very used to working on high performance cars. Not a hammer gun in sight and everything torqued up properly at the end of the job. A refreshingly nice gang of spirited blokes to do business with.

Hope that helps, Roger. Stay in touch.

Mike

[iRS]

Mike,

That's quite timely and very interesting. I shall check back in a few months to see what your lasting impressions of your new tyres are. I'm still amazed how much quieter my car is now its off Pirellis. Its a joy to drive again. You may remember commenting about it pulling to the left when you briefly drove it back in early summer. That's completely gone now.

Did I see somewhere else that you had a new windscreen fitted? I was told around a year ago that screens were not available for our cars, so good to hear that that's not true.

PS I hope the two photos at the top of your post weren't both taken at the same time - the whole car on trolly jacks?!!!

[J44EAG]

Yes, Roger. The whole car on jacks at the same time. No problems.

Nationwide fitted the windscreen less that 48hrs after I contacted the insurance company. They said availability was no problem at all.

Mike

[3.8etypephil]

My wife converted me to the use of seasonal tyres when I first drove her then car in the depths of a Hungarian Winter at -20c.
We have found Nokian to be the best Winter brand irrespective of price, not altogether surprising since they are a Finnish brand. Continentals are a little more expensive, but noticably inferior, for example. The Nokians cope with the XFR far better than the Dunlop Winters that the second hand Winter wheels came fitted with. The Dunlops have been relegated to the XJR, and although better than Summer tyres in the current low temperatures, thus equipped, the XJ is unable to put down the power anything like as well as the XF, despite the XF's 150 bhp power advantage. Investing in a second set of wheels and tyres for each car is a painful outlay, and can present storage problems, but is well worth it, especially if one plans to keep vehicles for a long time, or even to stay with a particular brand.

[J44EAG]

Some interesting observations being generated here.

I`m still "running in" my new boots. The wet weather grip with the new set is lower that the Avon ZZ5 which I had on the back end. I`ve only seventy miles on the new set so it is early days for me to form a true impression of grip capabilities. So I`m still slithering around a bit if I give the car a bit of throttle say on a roundabout. Break away though is quite predictable and controllable. I don`t really mind what happens at the back end of the car as long as I retain control at the front!

November weather is most unpleasant especially in the cold morning conditions with greasy semi-frozen tarmac. I`m doing a fair amount of country B-road work at present due to my Father being in hospital presently and having to do a twice daily run from Caterham down to East Surrey Redhill Hospital. So far, I`m happy with the new rubber wear on the R in its new virgin state. I`ll be even happier once we tow my Father back home. He is 89 today but we had to dash him into hospital with double pneumonia and a lung infection. Poor fellow is in a bit of a state but recovering slowly. Just glad I have the XJR to help make the trips as comfortable for us as possible. How I hate Mothers 1.6 auto 61 plate Focus with its brutal suspension and overly direct steering. It makes my carpal tunnel damaged hands sting and buzz.

Mike

Mike

[3.8etypephil]

At just seventy miles Mike, you are probably still running on the mould release agent; give them another one hundred and fifty before expressing disappointment.
For Summer use, our favourites are Bridgestone Potenzas (sourced from My Tyres) on the XF, and as Spring arrives, I plan to "borrow" the XF's Summer wheels to try on the XJ prior to any financial commitment. Both cars are on 255 35 20 all round (Winter) & 255 35 20 front / 285 30 20 rear (Summer).

[J44EAG]

I think you are correct, Phil. Now with about 100 miles covered, these tyres appear quite acceptable. They do run very quietly. They are in fact Gallapro manufacture not Jynti as on the invoice. Not worried about that as they are certainly coming on line nicely. A fair bit of muddy back lane use around Redhill Aerodrome. Loads of grease muck and slush. No problems at all and I`m to date quite happy with them.

Mike