Uniroyal Rain Expert 3 - Tyre Pressures?

[Midas]

I was running 13 inch rims and 185/70 A021s, on 18 psi. The ride height is set at 80mm under the sump.

I loved this set up and have waited until the last safe moment to change the tyres from the A021s.

In their place are Rain Expert 3 Uniroyals, initially at 18 psi.

My problem is that after doing now about 200 miles on the new tyres I am not impressed. I can 'sense' a lot of tyre wall movement, as if the car is squirming - indeed the turn-in is much poorer. You get the feeling the car is sliding before it does grip.

I know a lot of people are very happy with this tyre, so am I doing something wrong? Am I running them too soft?

Otherwise it is more money on Toyo R888s instead.

 

[Golf Juliet Tango]

I run on much the same set-up . I agree that it isn't quite as good as Yoko 21s but can not say I have felt it squirm as you describe.

[StevehS3]

I have the Rain Sports which is 185/55 so much lower side wall. I haven’t noticed excessive tyre wall movement but when pressing the side of the tyre with my thumb the side wall does feel soft at 18 PSI. I run mine at 20PSI.

[DJ.]

I have 60 profile on 14s and run 19 psi cold as I noticed more movement in photos at a track day. Try 20 psi. I know what you mean, I had an Elan with 80 profile tyres and used to put the tyre pressures up 8psi over the Lotus recommendation on a dry track day.

Duncan

Ps. They aren't as good a a021r obviously, but good in all weathers and safe in my experience.

[grumpy the 7th]

I blame the EU safety rule makers & the Brit government for not knowing sh!t from sugar when it come to common sense. Grrrr! for the lack of AO212's because they're too noisy at 73dB (just look at your wheely bins they're limited to 90 dB)

It'll be the same with the auto speed limiters coming with the 2022 edition of 'How to be an arse when in power'

Rant over...............................  

Back to the question. I've now reluctantly gone the Rainmaster 3 route and YES they do roll when turning in and leaning into corners. Your backside moves sideways even before you turn the wheel.

I used to run my 21's at around 15psi and found them more than firm enough to trust on corners. I've been increasing the pressures on the rainmaster 3's  by 1psi after a few blats over the past few months.

I've now got to 22psi where I think the car has almost the same feel as before.

HoHum

[Midas]

Thanks for the replies Guys - very helpful. I recognise all the symptoms above, so I will start raising the pressure.

[Midas]

Went out today with the pressures at 20 PSI and already a difference. I'll keep experimenting. On a positive side the grip is good, although I am comparing them to worn AO21s.

[grumpy the 7th]

DON'T go 2 psi more in 1 go but when you get to 22 psi, let us know what you think. You could even try another 1 for good luck. (I've not done so yet)

[Johnh]

20 psi on mine and no problems 

[Midas]

Over the last week I've driven about 750 miles in the Caterham - Belgium, France and East Anglia. Weather has been anything from drizzle and cold, to sunny and warm. In all this time I had the tyre pressures at 21 PSI. Tyres are 185/70 on 13 inch rims, so high sidewalls.

In East Anglia I was in the company of a group of friends with Sevens, and they were running Toyos R888s or Avon ZZSs, so I feel I have a good basis for how these tyres are working for me.

Compared to the A021s, they are a good alternative. They gripped really well in the dry, and were as good as the AO21s in the wet. I suspect that my friends with the Toyos and Avons have a bit more grip in the dry, as witnessed by a spirited afternoon of following them on a drive on twisty roads through the countryside.

I also noticed that the Avons and Toyos provide a wider contact patch - the tyres are 'squarer' than the Uniroyals, so this might also have an effect on grip levels.

After nearly 1000 miles there is little wear, and I would be surprised if these tyres don't outlast the A021s by some margin (I used to get around 4000 -5000 miles out of a set of the AO21s).

On tyre pressures 21 psi feels good with none of the squirm I first experienced. A well-regarded race engineer did tell me he thought that was too low - they have the Uniroyal as a control tyre on a number of their race series and he suggested 25 PSI.

Anyway, if you are after a good touring tyre at around £50 a corner, then the Uniroyals should be worth a look.

 

[Golf Juliet Tango]

I would agree with much the above.

They are great value, certainly.

I think AO21R are/were more confidence inspiring.

I have had no problems driving in the wet.

I don't value longevity, if they last for a couple of years that will do for me (see point 1). Discarding tyres full of tread is crazy. I have just got rid of the winter tyres for the Seven; although they were visually new, they were from 2011.

P.S. 25 psi? Nooooooo.  Unless Billy Bunter is keeping the car pinned to the track.

[Colin Cooper]

Also agree with Midas.

A positive from the passenger seat is the ride. The Uniroyals are much more compliant over bumps.

Col

[Wrightpayne]

Reading all the comments the Uniroyal does seem one of the best choices for touring / more sedate driver. Bit of extra ground clearance, good in the wet and cheap.

Just wondered how they compare to the Yoko A539. Anyone driven on both?

Ian

 

[Alastair B]

Not had Uniroyals but did have Yoko 539 on my car when I got it, I was not pleased with the grip with the 539’s for fast road driving and quickly changed over to A021 which were much superior,night and day comparison.