Are sliks directionl?

The Oily Bits S1 Specific Topics
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I got some slicks from deans on the rimstock,they have a direction of drive arrow.Forgive me for being a nurd but does this mean they should only be used one way round?If so they have sent me them fitted as two left feet

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Hi Brannan. Some slicks are, some aren’t. If they have a direction of rotation marked on them, then they are I’m afraid! [image]http://www.exiges.com/ubb/NonCGI/images/icons/frown.gif[/image] I’m not sure what the consequences of running them the wrong way would be, but I personally wouldn’t want to do it.

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Nither would ICheers Tony [image]http://www.exiges.com/ubb/NonCGI/images/icons/frown.gif[/image] [image]http://www.exiges.com/ubb/NonCGI/images/icons/frown.gif[/image] [image]http://www.exiges.com/ubb/NonCGI/images/icons/frown.gif[/image]

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Tony,How can something like a slick be directional? I thought the directional bit applied to the direction the tread rotated. Can you elaborate further??

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I’d imagine the internal construction is optimised for the direction of rotation. It may, for instance, overheat or under-heat if rotated the wrong way. I had to fit a “wrong” slick to due to a puncture in an endurance kart race once and I can’t remember noticing any great difference.

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Howard, like Jimbo says, the design of the internal construction is optimised in such a way that the tyre becomes directional. I believe that a directional slick, although it doesn’t have a tread pattern, can start delaminating / degrading if run the wrong way.

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I’ll have to have a closer look, next time I see a slick. I would never have thought to look for direction arrows. You learn something new everyday!

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quote:I would never have thought to look for direction arrows.Don�t worry about it, most people just think in terms of the tread pattern, and don�t stop to think about what’s underneath!

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The Yoko slicks for the Exige are definitely directional. I assume these are what you’ve got.The construction of the tyre considers the direction of rotation - in particular the interface of the rubber and the carcass.There may well be some directional component to rubber layer itself too. I don’t know about this there. I guess you’d not spot this so easily but would probably result in feathering/difference in surface between the tyres.There has to be a greater risk of delamination if these are the wrong way round esp. considering the increased load. Former colleague had two sets of race/track rim and tyres and destroyed one of the rears by not keeping them in the right pairings. He only discovered they were directional when he complained to Firestone (I think) assuming that one of the tyres was faulty given then other was behaving fine.Did Deans give/do you have any guidance on pressures? Mine still haven’t hit the road, Donington was a bit damp!

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No I have not been given any guidance on pressures either.Please let me know if you get a result.CheersBran

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Help!Does any body know the tyre pressures for slicks on a Exige??

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Brannan,If they’re the Yoko A005’s you’re talking about you should set the COLD pressures to the following:Fronts = 20psiRears = 18psiNote that these are COLD temperatures, when they are hot they should read:Fronts = 24psiRears = 25psiIf they are brand new, do 3-4 WARM UP laps to get some heat into them, them come in for 5mins to let the heat dissipate properly through the wheel/tyre, then go give it some stick [image]http://www.exiges.com/ubb/NonCGI/images/icons/grin.gif[/image]The one thing you will notice is a major difference in braking distance, you will be able to brake A LOT later than you would on road tyres. Obviously cornering speeds will be slightly quicker to, but as you gain greater experience with them you will learn to push harder as you have greater grip.Hope this helps.Deano

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Very detailed response nice one Deano [image]http://www.exiges.com/ubb/NonCGI/images/icons/wink.gif[/image]

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Hey Brannan,Let us know if you get any probs. There have been other reports that slicks knacker the uprights. Have you uprated yours?How about anybody else? Any runners with no probs?Cheers, Ian

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IDG,The upright issue will only be a problem if you have a car with aluminium rear uprights. As far a I know, most of the exige’s were fitted with steel ones. The steel ones have no problems what’s so ever. Brannan, Just another note I’ve thought of, get your geometry checked to make sure that your camber is set correctly. If you’ve got a standard car with normal ride height 112/122 then the normal camber setting will be fine.Deano

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quote:Originally posted by Deano:As far a I know, most of the exige’s were fitted with steel ones.I’m not so sure about that…

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OK so the easiest way to check would be to get a good old magnet on the job just to be safe.Deano

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quote:Originally posted by Deano:OK so the easiest way to check would be to get a good old magnet on the job just to be safe.Sure, but don’t forget that the aluminium uprights have steel inserts…

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Opps yep forgot that bit.

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Thanks chap its on the list of tricky questions for the dealer.Not that I’ll necessarily trust the answer!Cheers, Ian