GR Yaris Do not buy CUP2 tyres for track use

991RS said:
Second track day last weekend with same cup2.

To summarize, the tyre you see in pictures has done :
- One track day on the front axle with left/right exchange mid-day (low ambiant temperature)
- One track day on the rear axle with left right exchange mid-day (low ambiant temperature)
Second track day was very wet all day so I guess not hard for the tyre, except I oversteered (on purpose) all day long (it was very fun 😅 )


Next weekend Nurburgring TF with new AR1 :love:
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btw what camber etc are you running?
 
991RS said:
Same thing, It seems very high too me, but if it worked for you why not.....
What is the feeling of the car with such tyres pressure ? Any good laps time ?
I wonder.
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again, my suspension is stock apart from -3deg camber so there is some body roll.
my track has tight corners and quite grippy surface. I can get to 1.3-1.4G combined acceleration on street tires, and I pulled ~1.5G on Cup2's. Maybe this is why it needs more tire pressure? I don't know.

First I tried 2.2-2.4bar hot (32-45 PSI) but the tires started to roll on the shoulders pretty badly. I usually set my hot tire pressure based on temperature accross the tire and the inner-outter shoulders were much hotter with 2.2-2.4bar, it was most linear around 2.6-2.7bar.
This was one year ago, but even then I was settings lap times with the Cup2 that people on that track said would only be possible with more serious semi slicks -- I guess they didn't know how capable this car is on this type of track :-).

You can check out the track and my pace e.g. on this youtube video
 
991RS said:
Yes but the Yaris is relatively light so we should be able to run lower tyre pressure. 2.3 / 2.7 seems pretty high to me.
On a 991 GT3RS nobody runs 2.3/2.7 it's too high whereas the car is heavier than the Yaris.
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I think tire width (and maybe wheel width as well, i.e. tire support) also plays a role here. I am sure a 991 has much less body roll
1.3 tons is relatively heavy for a 225 width tire

BTW I also saw an Alpine 110R the other day on this track, Cup2's on its front tires were in same condition as ours :(:unsure:
 
Humptydumptyhadabigone said:
You can always do the simple chalk mark on the sidewall to see if you are rolling too far onto the side of the tyre. I am down around 2.2/2.1 cold on 60 sec sprints with AD08R and R888R. Yet to test the AR1.
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I am also constantly checking this, along with tire temperature pattern
For instance, the Goodyear F1 Supersports -- in stock size -- did not roll over the side with 2.2-2.4hot, the same pressure that would destroy Cup2, PS4S, CSC7 shoulders in no time.
Cup2 sidewalls seemed pretty stiff at low temperatures and on street, but they felt soft when reached 80+degC
 
Onehp said:
Great camera angle, can 'feel' the, excellent, pace. Where is the (go pro?) fixed?
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Lately I am fixing it on the bonnet, close to the toyota badge using a 3rd party suction cup type mount.
The other end of the bonnet, next to the windshield, vibrated a lot more.
Its really hard to find a good spot that gives some feel of the speed and doesn't look like granny was driving 🤣
 
Michael Knight said:
btw what camber etc are you running?
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I have KW clubsport V4 with a geo setup mainly for track but not 100% for track use.
On the sheet I got from Raeder Motorsport it says :

temp.webp
 
@Orion
So finally I understand we both had the same issue whereas we run different tyres pressure
Me : "low" tyres pressures
You : "High" tyres pressures
And same thing happened ! May be less violent on yours CUP2

I'll try some low and high pressures with the AR-1 to see what is the best.
 
Late to the party but I had the exact same experience with Cup2's in my GRY as the post owner, after the first track day the middle rubber was gone, pretty much like the pictures posted. Switched to Yoko AD09R and they have been fantastic (still to need to find optimum pressure but in the next track day)
 
DraPPer said:
Late to the party but I had the exact same experience with Cup2's in my GRY as the post owner, after the first track day the middle rubber was gone, pretty much like the pictures posted. Switched to Yoko AD09R and they have been fantastic (still to need to find optimum pressure but in the next track day)
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Useful to know. Thanks for posting.
 
Orion said:
Exact same issue
As you can see its really this second outter thread that gets destroyed.
I think its too soft, cant deal w/ higher lateral forces
I was paying extra attention on tyre temperatures.
Similar issue w/ otherwise excellent Continental SpC7
PS4s had some shoulder wear
GY EF1SS wear was fully even
All tyres used in same conditions, abused on same track, w/ lap times 41.4-41.8s
View attachment 23933
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IMO there seem to be an overspin problem, or overpressure when hot :unsure: in the pic the pressure is down again, but when hot maybe the weight focus contact in the schreded area
 
ordered a temp monitoring system so helps in keeping the tires in shape during drives. could maybe crank up front camber to -3 as driving less street with the car to help front tire temp
 
True, these Michelin PSCup2 are very good for fast road driving, but when it comes to track they seem a bit "fragile".

Have any of you tested the Yoko A052 ?
I had a set on for the past 2 years, did only one track afternoon, but easy to find the good operating pressures (as per OEM requirements) 2.2F and 2.0R seemed optimum that day (Autumn, warm day around 24°C with stock suspension & géo settings).
The rest of these tyres' life was spent on fast road fun, and even on the wet are unbelievable for semi-slicks ! They covered 8400 km before needing to be (legally) replaced, but were nicely evenly worn. The best tyres I have had so far ! Really recommend.
I have now PSCup2, happy for dry road, but much less at ease when wet.
Next set I plan to test are the Bridgestone Potenza RACE semi-slicks ? Unless I go back to Yoko A052...
 
micsub said:
True, these Michelin PSCup2 are very good for fast road driving, but when it comes to track they seem a bit "fragile".

Have any of you tested the Yoko A052 ?
I had a set on for the past 2 years, did only one track afternoon, but easy to find the good operating pressures (as per OEM requirements) 2.2F and 2.0R seemed optimum that day (Autumn, warm day around 24°C with stock suspension & géo settings).
The rest of these tyres' life was spent on fast road fun, and even on the wet are unbelievable for semi-slicks ! They covered 8400 km before needing to be (legally) replaced, but were nicely evenly worn. The best tyres I have had so far ! Really recommend.
I have now PSCup2, happy for dry road, but much less at ease when wet.
Next set I plan to test are the Bridgestone Potenza RACE semi-slicks ? Unless I go back to Yoko A052...
Click to expand...
no experience with Yokohamas, could be nice to test.
Agree that Cup2 is maybe too fragile for heavier track driving. Could make nice pairing with full blown track tyre - cup2 for fast road and then proper track tyre for serious track driving.
 
micsub said:
True, these Michelin PSCup2 are very good for fast road driving, but when it comes to track they seem a bit "fragile".

Have any of you tested the Yoko A052 ?
I had a set on for the past 2 years, did only one track afternoon, but easy to find the good operating pressures (as per OEM requirements) 2.2F and 2.0R seemed optimum that day (Autumn, warm day around 24°C with stock suspension & géo settings).
The rest of these tyres' life was spent on fast road fun, and even on the wet are unbelievable for semi-slicks ! They covered 8400 km before needing to be (legally) replaced, but were nicely evenly worn. The best tyres I have had so far ! Really recommend.
I have now PSCup2, happy for dry road, but much less at ease when wet.
Next set I plan to test are the Bridgestone Potenza RACE semi-slicks ? Unless I go back to Yoko A052...
Click to expand...
Maybe try the new AD09? Bit friendlier for street driving....
 
Onehp said:
Maybe try the new AD09? Bit friendlier for street driving....
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Yes, AD09 appears to be a very good semi-slick tyre (that is supposed to replace the A048 I understand). I have only driven them one dry track day on my MK Indy RR so far. I have these AD09 (205/50/15) on the rear, and A052 on the front (185/60/13 - because AD09 were not available in that size). Waiting for a damp / wet day to say which is best on the wet ! If I survive, that is, this car is already suspected by my wife for having tried to kill me !
 
Have been running AR1 on past couple of track days, had zero issues, Truth to be told, I was rather gentle with the car with 2 hot laps then 2 to cool down.

Running 235/40 as this was what was left from previous car (Megane RS). I'd say that wear on edges was much more prominent on Megane - maybe due to heavier car and more aggresive suspension setup (running stock GR).
 
The good thing about cup 2 is that they are cheap on stock size. But the Yokohama ad09 seems to be the best option out there for street and track use.

I have tried them in 245 size and can directly compare them to ar1s. The caveat is the speed code that is not Y and there is not 225 size atm.

AR1s are superior on dry track on feel and speed, but much worse on anything else, and a problem with rain.
 
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