Ive asked this question on SELOC recently but didnt get a full answer.Standard size rear tyres, AO48,s always seem to be a pain to get hold of in the right compound.Question,will a 235 /45 /17 fit onto a standard S2 Exige rear wheel and clear the wheel arch etc. They appear to be available in both M and MH from a few suppliers.
Dunno about your rubbing question but I’ve had a few sets from Bookatrack and never waited more than a few days for delivery? Cheaper than from a dealer, and Johnny even hand delivers to my house in person at a time to suit me! Can’t beat that for customer service!
I belive the std rear is a 7.5 and you need the 8 to fit the 235 tyre - could be wrong (but don’t think so !! )
There’s a great wheel chart thingy on SELOC which details all the S2 wheels with offsets etc
I switched recently from the A048 to the Toyo R888 for the same reason as in Italy it’s always difficult to have the A048 LTS delivered in reasonable times. I did only one trackday for the moment but I am very happy for the change.
I had the R888 delivered from Camskill in a very short periodo of time.
Jus do it!
Which ever tyre you use put some heat cycles through it
One of the lads on Scottish Elises Craig gotham tune,CC Chrome Orange Exige S had to get tyres on a recent trip and nipped over to the factory motorsport section
They told him just by looking @his tyres they were knackered (On there 3rd track day) ~he knew that which was why he was there for some new boots and they were the only place close to Snetterton with some
They told him that he hadnt put any heat cycles through them apparantly you need to put 2 through the Yokos and 4 through the toyo’s
So it might be worth doing a bit of research from what I remember it was some fasr road driving to ge the tyre temp up then allow them to cool to 10’C and do it again ~I don’t know if all the heat cycles have to be put into the tyres in the same session or if you can break it up with some lunch so worth asking the question if anyones knows someone knowledgable in the field
Although I suspect few tyre suppliers volunteer information on how to make your tyres last longer ~bar check your tracking and tyre pressures
cheers Hamish
[color:“blue”]My name is Alan Meaker, I am the Motorsport Manager for Toyo Tyres (UK) Ltd.
I was at Rockingham on the Saturday 1st March at the LOT trackday and worked with a couple of cars using our R888 tyre regarding pressures and tread temperatures.
What I would like to do is to offer some advice on tyre temperatures and pressures and how to achieve the best from our tyres when taking part in either trackdays or racing.
The R888 has a semi race construction (very stiff) and a race tread compound. The optimum tread temperature range is between 85C and 95C measured using a probe type pyrometer, and ideally a maximum difference across the tread of 9C. The maximum hot pressure we recommend is 40psi. Camber angles up to 5 degrees are permissible but the final setting will depend on tread temperatures. It is advisable to have as much positive castor as practical as castor induces a beneficial camber change during cornering. I recommend that the tyres be put through 2 heat cycles before hard use.
The pressures you use will initially depend on the weight of the car, too little pressure on a heavy car can lead to over deflection of the tyre and subsequent failure.
Below are some basic settings:
VEHICLE WEIGHT COLD PRESSURE HOT PRESSURE
Very Light < 800kg 17 - 22 psi 22 - 29 psi
Light 800kg - 1000kg 20 - 26 psi 24 - 32 psi
Heavy 1000kg - 1400kg 23 - 27 psi 28 - 40 psi
Very Heavy > 1400kg 27 - 35 psi 37 - 40 psi
As a tyre gets hotter the pressure increases, this is due to the moisture in the air. The cold pressure you set to achieve a desired hot pressure will depend on the conditions on the day i.e. ambient and track temperature, wet or dry. If the day/track is cold you will need to start with a higher cold pressure as the tyre will not get as hot therefore the pressure increase will not be so great.
Hot pressures must be balanced side to side. Once the tyres have cooled you will find that you will have a difference in pressure side to side, if you have been racing on a right hand track you will find the offside pressures will usually be higher than the nearside.
Changing hot inflation pressures by small amounts can be used to fine tune handling.
Reduce Oversteer Reduce rear pressures or increase front pressures
Increase Oversteer Increase rear pressures or reduce front pressures
Reduce Understeer Reduce front pressures or increase rear pressures
Increase Understeer Increase front pressures or reduce rear pressures
Achieving the required tread temperatures will depend again on the conditions on the day i.e. ambient and track temperature, wet or dry.
You often here competitors saying �My tyres started to go off towards the end of the race�, this is usually due to the tread getting to hot.
The tread temperatures are constantly changing through out a race, hotter when cornering and cooler when on the straights and cooling even more when you are slowing to come into the pits. Therefore the temps you record in the pits will be lower than those during the race. So if you record temperatures within the range given above the probability is the temps will be too high during the race.
Increasing your tyre pressures will cause your tread temperatures to increase, more pressure stiffens the tyre�s casing which results in the tread having to do more work resulting in the tread getting hotter. Lowering your pressures will cause them to decrease.
Inevitably changing one thing will affect other things, the whole set up of your car is a compromise between anything that is adjustable.
Some of you are also asking about different compounds. Originally we only had one compound �GG� (medium hard), but we have now introduced some sizes in a �SG� (soft/wet) compound. This was done primarily for sprint/hillclimb (around 60 second runs) where the distances covered are relatively short and you need the tyres to work/heat up very quickly. This is not a compound I would recommend for race/trackday dry use as the tyres will go off very quickly.
The sizes that will be available are:
185/60R13, 205/60R13, 195/50R15, 205/50R15, 225/45R16, 225/45R17.
Another subject is the introduction of our Proxes R1R. This tyre was due to be launched at the beginning of 2008, unfortunately this has been delayed to at least mid 2008 but there is a good chance it will be latter than this. Regarding sizes, initially we will have a rear fit (225/45ZR17) but not the front (195/50R16).
I hope this is of some use to you.
If I can be of any further assistance please give me a call.
01933 414537
Best Regards
Alan.
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A+P tyres supply Yoko’s in the correct sizes and should have stock (elise trophy official suppliers)
01494 525971 speak to Stewart
Thanks Pesky
I knew I’d read something before just couldnt remember where
cheers Hamish
I totally rate both tyres but so far in my 3 year Exige ownership (almost 3 ) mainly trackdaying I’ve yet to take either to the tread markers. Yoko’s gave wheel wobble despite rebalancing continually and Toyo’s just didn’t hold the road last track day (8/5/08). Had just done Spa hard for two days prior and about 6 others before that in the year. So what’s that… too many heat cycles, poorly run in or what?
I’m also unsure by what it means “put through at least two heat cycles before hard use” is that a couple of normal road drives ? I only ask because every trackday I go on someone is getting a new set of boots…Yoko’s or Toyo’s!
[quote)
I’m also unsure by what it means “put through at least two heat cycles before hard use” is that a couple of normal road drives ? I only ask because every trackday I go on someone is getting a new set of boots…Yoko’s or Toyo’s! [/quote]
What he said!
I have found that the A048’s are at there best on there first outing and they get progressivly worse and by there 5th heat cycle they are shagged. To be fair the Mediums are down to the wear marks by then as well, especially the rears.
just had my first experience at A&P… what a bunch of total… stars! very helpful offering great advice! certainly seem to know their stuff!