How to get heat into the tyres
Discussion
Fair question.
The car's not turned a wheel since September. I work overseas. Tyre pressures cold are normally 22psi all round for me. After disconnecting the trickle charger I checked the pressures and found more or less 19psi all round. I was about to top them up but thought maybe best to leave them be. So at 19psi I headed out. For about 12 miles on a Scottish A road (English B road) I maintained as close as I could to the speed of the road without provoking the car. After 12 miles I booted it out of a junction, turning right, and rode out the wheel spin in first, second, third and a nadge in fourth before easing off. The road was dry and not yet salted/gritted but damp in the shadows although not frosty. I wanted to know what braking capability was available so after that last change to fourth I deployed the anchors and for the first time (I bought the car in July '18) succeeded in locking the fronts. Although this is not the R, I still feel the standard setup runs way too much front negative camber for the road...
Beyond this I did nothing more to get heat into the tyres on the public highway. The braking test was enough to tell me what sort of margins I had to bear in mind. Traction issues are more of a constant so are mitigated against with judicious throttle application. The caveat being over rotation of the rears whilst cornering results in a more rapid break away than I encountered during the summer months. Nothing surprising in that.
I enjoyed being out in the car but didn't relish it to be honest. The skittishness of the setup in the summer was tolerable because I knew I could recover the odd lurch but yesterday with large vehicles doing what they do all year round I felt way more exposed and trimmed my speed accordingly. The one constant, summer or winter, is the absolute positive reaction form almost all road users. Such a joy to drive fast or not so fast.
The car's not turned a wheel since September. I work overseas. Tyre pressures cold are normally 22psi all round for me. After disconnecting the trickle charger I checked the pressures and found more or less 19psi all round. I was about to top them up but thought maybe best to leave them be. So at 19psi I headed out. For about 12 miles on a Scottish A road (English B road) I maintained as close as I could to the speed of the road without provoking the car. After 12 miles I booted it out of a junction, turning right, and rode out the wheel spin in first, second, third and a nadge in fourth before easing off. The road was dry and not yet salted/gritted but damp in the shadows although not frosty. I wanted to know what braking capability was available so after that last change to fourth I deployed the anchors and for the first time (I bought the car in July '18) succeeded in locking the fronts. Although this is not the R, I still feel the standard setup runs way too much front negative camber for the road...
Beyond this I did nothing more to get heat into the tyres on the public highway. The braking test was enough to tell me what sort of margins I had to bear in mind. Traction issues are more of a constant so are mitigated against with judicious throttle application. The caveat being over rotation of the rears whilst cornering results in a more rapid break away than I encountered during the summer months. Nothing surprising in that.
I enjoyed being out in the car but didn't relish it to be honest. The skittishness of the setup in the summer was tolerable because I knew I could recover the odd lurch but yesterday with large vehicles doing what they do all year round I felt way more exposed and trimmed my speed accordingly. The one constant, summer or winter, is the absolute positive reaction form almost all road users. Such a joy to drive fast or not so fast.
You will just have to wait until the weathers warm!
I bought my car on the south coast of England in October and when I drove it there it was great, yes you get wheel spin but the tyres hook up and consequently you can enjoy opposite lock slides which I love.
Since I got the car home to N.Ireland and the weather has been cold and grey I find slides are to be feared a little as the tyres don't hook up, they just keep sliding.
Its too cold and the rubber is too hard!
My car won't be out until the spring now anyway.
I bought my car on the south coast of England in October and when I drove it there it was great, yes you get wheel spin but the tyres hook up and consequently you can enjoy opposite lock slides which I love.
Since I got the car home to N.Ireland and the weather has been cold and grey I find slides are to be feared a little as the tyres don't hook up, they just keep sliding.
Its too cold and the rubber is too hard!
My car won't be out until the spring now anyway.
I've treated my tyres to about 7 Coats of hot lap and the rubber appears to be softer even tho the average temp is well downtown a before and after, I,m pretty friendly with a local Motorsport team who have a rubber measuring stiffness device I should have done a before and after, I'm also going to have a custom cut applied to the zzr and see how that goes after all the tyres are so cheap it's worth a try along with a proper set up when it warms up a tad Spring is coming I saw some new born lambs jumping around in the fields last week that's a real pointer were going in the right direction.....
I have a 220bhp superlight R which I have used over the years with Avon CR500 / ZZS & ZZR. I have also competed in sprints and on track with most Avon tyre combos.
I have tried all 3 tyre compounds of the ZZR (soft A24 / medium and then the 620R commissioned compound). Unfortunately I cant run MSA blue book list 1c tyres so I can now only use the 620R compound which is slightly harder than the medium compound. I can also confirm that the ZZS and ZZR are definitely not the same compound.
I had a discussion with the director of motorsport for europe at Avon regarding selecting tyres for the superlap scotland which has a one lap final around knockhill. You have an outlap to warm up tyres then a flying lap. So getting heat in the tyres is key. He recommended the ZZS would be higher up its temp gradient and closer to the ultimate grip (although he reckoned 4 laps min to get up to ultimate grip) than the ZZR would be. I did a bit of testing with a vbox and found that was mostly true, but if the ambient temp was above 15c or so then it swung to the ZZR being the better tyre for the flying lap.
If you are not competing then see if you can get a hold of soft ZZRs as the best bet. My wet weather tyre on track and also the road tyre is the ZZS, its a very good tyre and is better suited to cold weather but ultimately you can very easily spin the rears if you want to. I havent tried the CR28 as again it is a list 1c tyre, I would imagine it would be better in the cold weather.
My conclusion is that the ZZS makes a great road tyre (not surprising since caterham developed it with Avon) and should be fine for winter. Have a separate set of alloys and put the ZZR on for track. I have been caught out on track in the rain with the ZZR and they arent too bad in a track environment as long as there isnt standing water. I wouldnt bother altering the tread pattern of teh ZZR, you are just compromising dry weather ability.
Hope some of the above helped!
I have tried all 3 tyre compounds of the ZZR (soft A24 / medium and then the 620R commissioned compound). Unfortunately I cant run MSA blue book list 1c tyres so I can now only use the 620R compound which is slightly harder than the medium compound. I can also confirm that the ZZS and ZZR are definitely not the same compound.
I had a discussion with the director of motorsport for europe at Avon regarding selecting tyres for the superlap scotland which has a one lap final around knockhill. You have an outlap to warm up tyres then a flying lap. So getting heat in the tyres is key. He recommended the ZZS would be higher up its temp gradient and closer to the ultimate grip (although he reckoned 4 laps min to get up to ultimate grip) than the ZZR would be. I did a bit of testing with a vbox and found that was mostly true, but if the ambient temp was above 15c or so then it swung to the ZZR being the better tyre for the flying lap.
If you are not competing then see if you can get a hold of soft ZZRs as the best bet. My wet weather tyre on track and also the road tyre is the ZZS, its a very good tyre and is better suited to cold weather but ultimately you can very easily spin the rears if you want to. I havent tried the CR28 as again it is a list 1c tyre, I would imagine it would be better in the cold weather.
My conclusion is that the ZZS makes a great road tyre (not surprising since caterham developed it with Avon) and should be fine for winter. Have a separate set of alloys and put the ZZR on for track. I have been caught out on track in the rain with the ZZR and they arent too bad in a track environment as long as there isnt standing water. I wouldnt bother altering the tread pattern of teh ZZR, you are just compromising dry weather ability.
Hope some of the above helped!
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