To see if they move relative to the wheel. Apparently tires move easily on forge wheels due to it's smooth inner wheel surface. My wheel shake badly on the track after couple track events and my wheel balance is all off. I could not figure out why until I mark the tire position relative to the valve stem on my CCW wheel and the darn thing move by about 1-2 inches after two track sessions. Some race cars drill hole in their wheel and screw down the bead of the tire to prevent it from sliding ... I am not going to do that

Easy fix is to rotate your wheels from side to side let's say 1/2 way through your track event to even things out (if you don't have directional tires). I am going to give that a try to see if I can keep the wheel balance relatively intact.

 

That's amazing....I would have never thought the tire would spin on the rim like that.

 

interesting......

very good research techniques too

 

You should also check your rotors, the spider cracking is getting to the point where it is time to swap rotors.

I would recommend slotted (Brembo or Giro) as the drilled are bad for the spider cracking.

 

Ah, that's what you meant. I misunderstood you when you spoke about this at T-Hill. That's amazing. It was good meeting you, albeit briefly, and I'll see you on the 11th.

 

Yes, a simple mark on the tire does the trick

What crack? .... lol

It was nice meeting you too. I had bad brake pads and off balance wheels last time out at Thunderhill ... how horrible. Glad you sign up with Lotus club. Will see ya in couple weeks

 

You should have the wheels checked for proper dimensions.
If the bead seat was machined to the smallest part of the SAE (USA) or ETRTO (European) standard, or is out of spec, the tires just may just be too loose on the rim.
It is quite rare to have the kind of slippage you describe and inexcusable in a competition wheel. For really high load or high horsepower applications, we recommend building the wheels on the very tight side of the bead seat spec and knurling the bead seat (this technique is used by Nissan on the GT-R).
Wheel vibration is very distracting, can affect traction and ALWAYS has a negative impact on driver concentration and confidence.
Lastly, we recommend all competition wheels hold to a maximum radial and lateral runout of .3mm (.012 in). This will provide superb smoothness at speed and allow you to concentrate on having fun or passing the guy in front of you.

 

Very common problem especially with slicks. I had tires doing almost a full spin on wheels in the past... Make sure your tire dealer do not grease the tires when they mount them and use degreaser instead. One good trick is also to use some spray net to "glue" them to the wheels.

 

Interesting suggestions. Many have report the same issue on rennlist as far as tire slipping on forge wheels. Some use hair spray to mount the tire and that seems to minimize the slip somewhat ...