Those little hole things in the tyres

[speedy king]

I know they're there to show how much grip is left (honest, i'm not as thick as i may sound ) however what difference does the depth of the hole make? I've always run with in my head the assumption that you don't change them when they only have 2/3 mm left but when they're about quater to half warn down, is that right or am i wasting my money? This occured to me as my current Vega slicks have done two race days (club level) and are now coming up to their third and i've been suprised with how deep the holes still are on the rear and a Senior racer at my local track (Ellough) said that the track surface seems to prefer worn slicks over new ones.

Still following?

Is it possible that some tracks prefer worn tyres and how deep or shallow should the holes be before i throw them in the "spares" pile?

[Mackmot]

Tyres will only be good for a qualifying session maybe less. Then they will be the same for about 100kms as long as you keep siding and turning them to even the wear.

[speedy king]

So, it's better to slide? And on a new set by the team i get to Heat two (completing two practice sessions and heat 1) i'd be the same as people on warn tyres?

[Mackmot]

Pretty much, there will be a small advantage to the newer tyres but it is negligable. They tend to last a bit longer during a race when they are newer before they go off and need to cool down again but there wont be much difference in laptimes at the start of the race.

[Revracing]

I would like to add my two penneth to this one, During my own karting stint we experimented a great deal with this one, what we found was that "used tyres" performed pretty much the same as new ones up till the second race meeting (or 1 race day and 1 test day, which is what we settled on) at championship level. We used to extend this to 3 or 4 sessions at club level with no significant loss of performance.
Losses tended to materialise in less efficient grip under braking and greater tendancy to slide wide under acceleration out of corners. which you should be able to get away with at club level.

Before the new tyre rule was introduced at championship level we only used to buy new rears every other race, and baring punctures a set of fronts would do half the season, we did this to balance the grip levels front to rear.

If your setup is good then hot weather will bring out the advantages of newer tyres even more...

[Mackmot]

Ive just thought, Im talking about radials do you use crossplys in Karting? Cos revracings comments do sound like crossplys

[Revracing]

Mackmot, Can't say as i've ever looked into their construction, I still have bucket loads of old tyres lying around, I'll have to have a look....

[speedy king]

The current Vegas i have have done two club race days (3x 10 lap heats, 14 lap final of 800m circuit per day) and the holes have got about 25-50% shallower so they should last me for Monday?

[DSM]

Most of the tyres used in karting are x-ply. The holes have nothing to do with the grip, they just indicate how much tread rubber is still on the casing. The tyres will gradually harden each heat cycle and can certainly lose a lot of grip well before the holes have disappeared. in fact, once the tyres have reached a certain state, they will physically wear more slowly but will have lost an awful lot of grip.
Revracing - that's very unusual in my experience fronts usually wear out more quickly than rears. Half a season? wow!! Again, we always found tyres well past their best after, maybe, a couple of racedays, 1 test day.

[speedy king]

Would a very grippy track surface compensate for not such grippy tyres? (3rd race) As like i said in my first post, i know of a Senior Rotax driver who won a heat on his 3rd race day with the same Vega's? The surface at Ellough is very grippy

[Revracing]

DSM, it was down to my driving style, whatever I race I always need less grip on the front than the rear (I like a degree of understeer).
People used to watch me and wonder how I got round because they couldn't see any steering input.
Hence a very low front wear rate.

[DSM]

Not arguing! Just surprised. However, are you mixing up under/over steer?
If you are getting round with very little steering input then the kart is oversteering (loose) and the fronts won't slide and would minimise the wear.
Understeer would imply sliding front tyres (push) and a higher rate of wear.

[Redlake27]

Are they to put the wheels into?

[G Halls]

I Have had trouble with new tyres at ellough in the past, have been told the track does favour worn tyres by a few people so there must be some truth in it

[Alex Hodgkinson]

When you say you've "had trouble with new tyres" what kind of trouble do you mean exactly?

[G Halls]

we ran a prokart in a race here a couple of years ago and started with some very lightly scrubbed new tyres the kart was off the pace in qualifying and for the first 10 laps of the race as the tyres wore they gradually came in and the L/times dropped
The same problem was experianced by a cadet that we ran last bank holiday new tyres and again no grip.
old tyres were fitted and the lap times dropped

have heard the same thing occuring from a couple of other racers at that track so must be something in it

[speedy king]

Is it best now it's October and getting pretty nippy to take the wheels off and keep the tyres in an airing cupboard to keep them warm? They apparently get damaged in cold weather and need to be kept warm?

Kinda sweet really, i may put a blanket over them!

[Revracing]

The idea is keep them at as constant a temperature as possible, room temperature is fine. The thing to avoid is heat cycles i.e warm then cold then warm again. Otherwise your tyres will end up like blocks of wood....

[speedy king]

So as it is getting colder outside now i'll just bring them inside to keep them to a similar temperature as what they were in, but not put them in a warm place such as an airing cupboard

[Revracing]

An airing cuboard is probably the best place for keeping a constant temperature. I used to pack mine round the boiler flume in the loft...... worked a treat

[MMiller]

Take your tires - unmounted.... wrap them in seran wrap then take a heat gun and heat the wrap so it wraps around the tire (you can also use a hair dryer)... then take a garbage bag and take each set and tie them up in the bags. I stored mine in my basement - anywhere with a constant temperature... this has been the best way to keep tires during offseason.

As far as the wear indicators - they are only there for reference. I've had tires that have lost very little grip all the way down to where the indicators were gone.. then other sets where the tire looked brand new but it had so many heat cycles that the tires were junk. Lap times are the only way to truly tell. Testing is the best way to find out if scuffs will be better for stickers or not. A lot of times the stickers will be super slick then come in quick and set a faster time but level out faster... if you go too many laps.. they lose longevity and the tires will wear out faster over the next few sessions.. compared to scuffing a set in - letting them cool then using them - they tend to last longer.

Hope that helps.