Track Days - Are Slicks Allowed?

stockcar · Post by **stockcar** » Fri Nov 17, 2006 9:09 pm

generally speaking, most slick type tyres will operate best at a HOT pressure of around 30psi...............

you will need to gain a little experience to judge where to start your COLD base pressure to achieve the correct operating set-up

cheers, alyn

jdening · Post by **jdening** » Thu Jan 04, 2007 9:02 am

Andy916 wrote:As for rollover probability, I'm not convinced it's any more likely than with trackday tyres. Sure, going from road tyres to trackday tyres you increase the cornering forces, and increase them potentially further with slicks. But, how handleable it is depends on progressiveness and predictability of a slide more than anything.

cheers
Andy

Arf arf! Andy's about as progressive as a well aimed half brick. And I stuffed him once on a TZR in a race at Cadwell.

We won't mention the fact that I wrote off the bike on the very next corner, if I recall correctly. Bit careless, that...

Wotcha Frogman!

IWANT1 · Post by **IWANT1** » Thu Jan 04, 2007 12:56 pm

Stupid question :!:

But why do u need a cage if using slicks :?:

andycaca · Post by **andycaca** » Thu Jan 04, 2007 1:01 pm

IWANT1 wrote:Stupid question :!:

But why do u need a cage if using slicks :?:

slicks give you more grip when theyre hot, more grip means higher corner speeds which means in the event of an off, that accident is likely to be larger. the cage will help protect you

jungle-jim · Post by **jungle-jim** » Thu Jan 04, 2007 1:14 pm

but is that often?

surely relying on road tyres requires more safety?

its worrying if track days get more restrictive over the coming years!!

typical nanny state stuff.

i will start going to paul ricard or mangy cours

or better still. go to spa a couple of times a year!!

IWANT1 · Post by **IWANT1** » Thu Jan 04, 2007 1:28 pm

just seems like over kill better tyres more chance i wont have an off as its my tyres that have given in not me?. Fair play in a real racer but for a track day that little bit more grip to shave some time off seem's good to me without the need for a cage

jdening · Post by **jdening** » Thu Jan 04, 2007 2:09 pm

IWANT1 wrote:just seems like over kill better tyres more chance i wont have an off as its my tyres that have given in not me?. Fair play in a real racer but for a track day that little bit more grip to shave some time off seem's good to me without the need for a cage

With my serious hat on for a moment, there's a massive (and dare I say incorrect) assumption there, that slicks behave just like road tyres, but with more grip. Not true, IMHO.

That simply ain't true. For example, slicks are a bastard to warm up - going out on cold slicks is like ridin..erm, driving on marbles - feels like it's greasy and 3 degrees underfoot. But the biggest problem is on the limit. Tyres are funny things - some slide progressively, and others let go with a bang. Slicks in general are designed for the ultimate in grip, so the rubber compounds tend to be designed with maximum grip, rather than maximum forgiveness in mind.

It's not *when* they let go that screws you, it's *how hard*. Road tyres tend to be designed to slide progressively, giving you plenty of time to release the numpty pedal in your cockpit. Slicks hang on and on and on and WOOOOAH!!!! Hello Mr Tyre Wall. DAMHIKIJFKOK. :?

As a secondary factor, it may also be that cornering speeds are that much higher so when tyres do let go, the accident is that much bigger. You may say that if you have more grip, you're less likely to have an off - I would say that is total bolleaux. Show a track fiend a grippier set of tyres, and I'll show you someone who goes 'Kewl! I'll 'ave some of that!' and promptly starts pushing a bit harder round corners.

As a tertiary factor, possibly there has been a history of other parts letting go (suspension mounts etc.) because of the additional stress caused by slicks.

Whatever - the fundamental is there - give people higher corner speeds, and the accidents will be bigger.

J.

Post by **Stuart** » Thu Jan 04, 2007 4:29 pm

:patself:

Fine post

IWANT1 · Post by **IWANT1** » Fri Jan 05, 2007 4:19 am

I would say that is total bolleaux.

Bit Harsh as I have never used full sliks just asking :!:

Good points tho maybe try some cut slicks if i can find some new rims
l

jdening · Post by **jdening** » Fri Jan 05, 2007 8:55 am

IWANT1 wrote:
I would say that is total bolleaux.
Bit Harsh as I have never used full sliks just asking :!:

Good points tho maybe try some cut slicks if i can find some new rims
l

OK, serious hat back on

Traditionally, the big advantage of race tyres for trackday use is cost. Race tyres don't have to be MOT/DOT certified, and don't need to cope with real world use (i.e. potholes and the like). THey are also more fit for purpose.

But don't expect miracles. Yes, there is a big gulf between something like an R888 (e.g. Racetek/208GP on a bike) and a road tyre like a Prox (e.g. 207ZR on a bike).

But you will find a relatively small difference between a good semi-slick, and a full slick. The compounds used will be similar. The extra tread (what tiny <5% there is) makes FA difference - look at F1 tyres with tread on them!

BUt they should be a lot cheaper, certainly compared toa fast road tyre (e.g. Pole Position, Mich Pilot, Chunghwa Sliderator Special)

In a lot of ways semi-slicks are a better idea as they will cope with rain a bit better, and will warm up quicker, and warmers are a pain on trackdays.

You'd be amazed how fast you can go in the wet with semi-slick or even slick tyres....when I was a youngster at Brands once...waffle warble scrote bleat etc......szzzzzz....

James