Just thought I'd seek peoples opinions regarding tyres losing grip with age.

I'm still getting used to my Spyder. I took her out for a quick spin at the weekend and nearly did! (twice!). To be fair the road was quite greasy and I've not really got used to driving a lightweight rear wheel drive car. My last RWD was a MKIV Cortina that I sold back in 1989. I remember having fun power sliding the rear on that (in the days when power meant about 70hp - bog standard 2.0 pinto). The GTM seems to be quite keen to step out of line at the rear on relatively light throttle changes and the traction pulling away isn't as good as I'd hoped with the weight mostly on the driven wheels. Now I'm more aware its likely to happen I'm ready to lift off and opposite lock and starting to think it could be quite fun to enjoy some fairly low speed sliding. This is with a 1.6 so I'm thinking the 1.8 VVC must be quite a handful though. Do other Libra/Spyder drivers find them tail happy?

I'm thinking about the tyres. They are Goodyear Eagle F1, 205/45/16 all around with loads of tread (at least 6mm). I've always thought of those as quite good tyres. Checking the date codes it seems they must have been with the car its whole life as the car was registered May 2004 and the tyres are all coded around week 40 of 2003. The wear seems to be even on all 5 (the spare is on a matching alloy). Seems hard to believe that even with swapping them around that 15,000 miles could be done on just 2mm of tread wear. Although the car spent the first 9.5 of its 10.5 years with a 1.4 single cam single point injection engine so maybe wasn't driven very hard.

I've checked the tyres and they have no obvious visible signs of wear, no cracks or suchlike, in fact look like new. I'm advised she's always been garaged so no overdose on sunlight or extremes of temperature.

So, I'm wondering whether purely their 11 years of age would have made them hard and slippery. If so, how deep would the hardness go? Would a few doughnuts scrub enough hard rubber off to reveal something softer and grippier underneath? Maybe I should just ditch them and get a set of R888s but it somehow offends me to waste so much treadwear depth. If I knew for sure that they have gone off it would make it an easier decision but a nagging concern says what if its no different with new rubber...

Certainly their age will not be helping 11 years is old for a tyre! Rubber does age especially from UV etc.

Neil

before you spend money on new tyres it maybe with giving tyre softener a try as you could do all tyres a few times for less than the cost of one new tyre and if there isn't any improvement you won't have spent as much as new tyres

What tyre pressure are you running? it sounds like you may be too high.
I am running 18psi front and 20 rear. I know of people who are running as low as 14psi.

I should have added that my car is a Libra.

Thanks for the responses. Following advice back from a similar post on the Bristol Kit Car Club forum I checked the tyre pressures and found them to be at 32 all round. When I bought the car I only did a visual check and there was plenty of tread, even wear, no cracks splits or bulges so didn't actually check the pressures. Even if I had I probably wouldn't have thought there was anything wrong with 32 as most "normal" cars run that sort of pressure. I've now dropped them down to 22 back and 21 front (based on the average of the advice I've now had/read). I didn't have a chance to drive it today to see if its made much difference but the contact patch looks much bigger and the sidewalls don't appear to be bulging out or looking under-inflated in any way.

If this improves things (and based on stories of other kit cars using "normal car" pressures when they were newbies and scaring themselves I hope it will) I'll keep using them for the winter to get a bit of use out of all the tread that's left and maybe go for some R888s for track day season!

I'll look into tyre softener - didn't know it existed!

Tyre pressures will have a huge effect on how it feels

possibly some useful reading

http://wiki.seloc.org/a/Tyre_pressures


Neil

Well, it looks like the tyre prsssures were certainly a big factor. Unbelievable difference. With 32 in them I was having to be really gentle with the throttle to avoid having the back kick out. Now with 22 I can boot it as hard as I like and it just grips. If this is how it grips with 11 year old tyres then it must be awsome with fresh soft rubber. Maybe I do need a VVC after all! Thanks for the responses.