Tyres skipping on full lock

[scoates]

Moderator note: copied from another thread and edited

Also has anyone noticed the tyres skipping when manoeuvring on full lock e.g. parking? Not sure if an Emira thing, a Cup 2 thing, or just a Cup 2 in cold and damp conditions thing.

 

[d15b7]

The skipping when parking is most likely the LSD being tight/aggressive. When making maneuvers like that with my Camaro ZL1 1LE there is all sorts of knocking/ratcheting from out back (especially with the GY 3Rs on there. I promptly bought another set of wheels/tires and mounted Falken RT 660s which are a thousand times more streetable!). The ZLE has one of the most racy/aggressive LSDs out there on a street car, and it shows when making tight parking moves.

 

[Forlorn]

I've got my car booked in to get the Cup 2s changed for the Eagle F1 SuperSports tomorrow so will hopefully be able to do a wee comparison on the ride between the two. I haven't been able to drive properly with the Cup 2s due to weather and road conditions so can't give any performance comparison. Will also see if the tyre place will let me weigh the wheels while they are off as I can't remember if we have any actual weights measured yet, but not sure if I'll be able to if they're too busy.

Also has anyone noticed the tyres skipping when manoeuvring on full lock e.g. parking? Not sure if an Emira thing, a Cup 2 thing, or just a Cup 2 in cold and damp conditions thing.

Evora was the same, something to do with Geo set up.

 

[KJD]

Evora was the same, something to do with Geo set up.

Look up Anti-Ackerman effect.
All Lotus (and some other cars) do it to some extent.
Nothing to do with the LSD. That’s at the rear, and this is a front geo/steering thing.

 

[mjw930]

The skipping is more than likely the Ackerman Effect when the fronts are in full lock and yes, the Cup2’s exaggerate this as there’s very little tread “wiggle” to absorb the sliding.

Explaining the "Ackermann Effect" in the 2014 Corvette Stingray - McGrath Auto Blog

If you take the all-new Stingray for a drive, you may notice something before you even leave the parking lot. This little something may seem like a defect, but it’s not. It’s called the “Ackermann Effect”, and although the issue was resolved 200 years ago, Chevy left it alone on the Corvette...

www.mcgrathautoblog.com

 

[Shahaf2911]

Look up Anti-Ackerman effect.
All Lotus (and some other cars) do it to some extent.
Nothing to do with the LSD. That’s at the rear, and this is a front geo/steering thing.

Exactly, also some Porsche cars do it, the panamera had it for sure, the 718 and 992 might have but I’m not certain (at least one of them did it for sure).

 

[schorsch]

I have the same issue on my Evora S (front tires skipping). The effect is significant and I was wondering whether the car has an issue or whether this is normal. I only own the Evora for 3 months now and it is my first Lotus. My Emira is arriving in a few weeks and I was hopong that it doesnt habe that problem.

 

[TomE]

The skipping is a consequence of the steering design and is nothing to worry about. It’s disconcerting when it happens for the first time but not a sign of a problem. Evoras do it too.

 

[ADC]

The whole Ackerman steering thing is super interesting... and I feel like a total noob for not having heard the actual term/name for it before
Excuse me while I go and geek out about steering geometry for a bit....

 

[Tonyshepp]

Some Mercedes’ cars some suffer from it, they call it crabbing. I drove a manual 2020 plate vantage which suffered from it in the wet on full lock and slow speed, yet the Auto version didn’t which was weird. None of my cars have ever done it.

 

[JohnHoward]

As others have said 100% Ackerman Effect, my F type was the same, also happened on my 410 Sport. It is indeed disconcerting the first time you experience it. For any passengers that haven't experienced it, you can have a bit of fun by saying "Oh no, is that back wheel loose again" and then give it the beans

 

[Toomanyloti]

Exactly, also some Porsche cars do it, the panamera had it for sure, the 718 and 992 might have but I’m not certain (at least one of them did it for sure).

We have two Taycans a RWD and 4s and they both do it. (on goodyears)

 

[emiraspain]

Yes 911, 718s..... do it... when on full lock, although its potentially for other reasons....
Just ease off full lock a little and it will prevent it. It may not prevent you from hitting other cars while parking, BUT you cant have everything.... And if you hit a porsche or a BMW< then you've done well by Lotus

 

[Evotion]

All my cars do it.

 

[emiraspain]

All my cars do it.

funnily enough, now I think about it, only good cars do it..

 

[BeHappy]

My R8 used to do it - I was told this is normal

 

[scoates]

After getting the tyres changed to Goodyears today I have noticed a lot less of the skipping. Still slight I think but might have been exacerbated on the Cup 2s due to dampness/temperature which definitely doesn't seem to affect the Goodyears as much.

 

[TomE]

The shape of the tread block, pattern of grooves and tread depth will also affect it.

 

[NicolasB]

My R8 used to do it - I was told this is normal

Yes, mine does it. Don't like that