tyreleader cups performance on track :(

khooni · 04-08-2015, 08:33 AM

with a set of "new" 2012 Michelin pilot sport cups from tyreleader, i went to silverstone GP yesterday to try them out.

Other than the bonnet catch issue (thanks Shimmy), the cups started ok but degraded consistently throughout the day with even weather conditions and track becoming grippier due to laid rubber. I went from a 2.40 to a 2.49 from 1st session to the final session at 4pm. Dropping at least 1 sec per session of about 5 laps. The car got noticeably edgier, I couldn't turn in as well and once turned in , I couldn't get on the power as much. I also couldn't trail brake very well into the lower speed stuff. It stops ok but I think that was because of my inability to carry enough speed.

This is my second set form tyre leader. The first set was great. I had no issues and they performed flawlessly for 5 trackdays. Even at the end, it felt loads better than the new ones I had, except maybe for the first session. The last time out I got 2.38 so I am bit annoyed that with new tyres I am slipping backwards.

Any suggestions as to why? Have the tyres been heat cycled to death (why and how?). Are they simply too "old" such that the compound hardens right after the first layer wears off? If you ask me now, I'd only be buying proper NEW tyres i.e. made in 2015............... too much of a gamble for me.

**alexk** · 04-08-2015, 09:09 AM

What tyre pressures ?
What suspension ?
What geometry settings ?
What tyre temperatures ?

Rick H · 04-08-2015, 09:25 AM

I bought a similar set from Tyreleader.

I'm not really any good as a judge, but my car was recently driven by a racing driver on Anglesey and he remarked specifically on the huge amount of grip the car had.

You got 5 trackdays from a set of Cups ? ? ? ? ? ? Is that normal ? ? ? ?

khooni · 04-08-2015, 11:26 AM

tyre pessure is 35psi all round.
suspension is kw clubsport (gen 1) non adjustable
track geometry setup by simpson motorsport

none of the above had changed. I just went on a track day at Snetterton 2 weeks ago and the grip was fantastic.

Yes.. 5 trackdays on a set of cups.

Yes the previous set had a huge amount of grip as well. Maybe this is a 1-off... but.. wtf.

billyboysm3 · 04-08-2015, 11:35 AM

Quote:

Originally Posted by khooni

tyre pessure is 35psi all round.
suspension is kw clubsport (gen 1) non adjustable
track geometry setup by simpson motorsport

none of the above had changed. I just went on a track day at Snetterton 2 weeks ago and the grip was fantastic.

Yes.. 5 trackdays on a set of cups.

Yes the previous set had a huge amount of grip as well. Maybe this is a 1-off... but.. wtf.

I run 30 psi hot, how hot was it yesterday.

mattCSLnut · 04-08-2015, 03:19 PM

Your tyre pressure was too high @ 35 psi (hot or cold) and Cups are very sensitive to both pressures & temperatures. Sounds like you were overheating them from the start.
On track the correct tyre pressure for Michelin Cups is 26 psi (cold) and should hover around low 30's psi hot unless there's something amiss.
The 2012 DOT is perfectly acceptable as the rubber life span of these tyres is around 5-6 years (if they were heat cycled correctly from the start) although they don't phisicaly tend to last that long if you track your car frequently

khooni · 04-08-2015, 04:18 PM

Hi Matt,

I accept that the pressures could be a bit high. What it doesn't account for is consistency of the track and why it degrades evenly through out the day.

It should be a 1-time.. oh that's bad and remain the same. But it doesn't, it just constantly goes down. NB I have tried these 35 psi HOT temps for 8 trackdays now and have never felt the tyres going off the way they are doing now. Gradually rubbing off performance the entire day such that at the end, it was basically understeering everywhere.

I'm going to try again and see if i can get new cups on soon and report back.

billyboysm3 · 04-08-2015, 11:38 AM

And how many laps per session,

khooni · 04-08-2015, 11:49 AM

5 laps.

22deg ambient temperature.

It just wasn't turning in and when I put the power down it just wanted to understeer. My car is setup to understeer so I can brake as late as possible and trail. It's gives me great confidence in that the tail won't snap on me and just gives me the extra turn in required when trailing the brakes. Yesterday it was just a pig, and when i gave up setting times and wanted to hoon, I discovered that because my front end doesn't grip, I have difficulty booting the tail out. The symptoms are that the tyres are fooked.

I'm buying a new set now. ............. but i'd appreciate if anyone thinks it could be something else..

oh, 1 more thing. that bonnet is really irritating me... I'm gonna tape it shut with masking tape.... is it ok to use masking tape on the paintwork?

billyboysm3 · 04-08-2015, 12:02 PM

Grant went to Silverstone a few weeks ago and that had poor grip, Id say tyre pressures to hot and track had poor rubber laid down on it.

04-08-2015, 08:33 AM	#1
khooni S5 - Full Throttle Join Date: Aug 2012 Location: east london Posts: 309 Casino cash: $3592	tyreleader cups performance on track :( with a set of "new" 2012 Michelin pilot sport cups from tyreleader, i went to silverstone GP yesterday to try them out. Other than the bonnet catch issue (thanks Shimmy), the cups started ok but degraded consistently throughout the day with even weather conditions and track becoming grippier due to laid rubber. I went from a 2.40 to a 2.49 from 1st session to the final session at 4pm. Dropping at least 1 sec per session of about 5 laps. The car got noticeably edgier, I couldn't turn in as well and once turned in , I couldn't get on the power as much. I also couldn't trail brake very well into the lower speed stuff. It stops ok but I think that was because of my inability to carry enough speed. This is my second set form tyre leader. The first set was great. I had no issues and they performed flawlessly for 5 trackdays. Even at the end, it felt loads better than the new ones I had, except maybe for the first session. The last time out I got 2.38 so I am bit annoyed that with new tyres I am slipping backwards. Any suggestions as to why? Have the tyres been heat cycled to death (why and how?). Are they simply too "old" such that the compound hardens right after the first layer wears off? If you ask me now, I'd only be buying proper NEW tyres i.e. made in 2015............... too much of a gamble for me.

04-08-2015, 09:09 AM	#2
alexk Driving it like I nicked it Join Date: Mar 2009 Posts: 2,786 Casino cash: $29971	What tyre pressures ? What suspension ? What geometry settings ? What tyre temperatures ? __________________ www.clubcsl.com - I am a BMW Motorsport fan ! My youtube channel is here

04-08-2015, 03:19 PM	#6
mattCSLnut CSL Register Uber-poster! Join Date: Sep 2009 Location: Cambridge Posts: 6,460 Casino cash: $27763	Tyre pressure too high Your tyre pressure was too high @ 35 psi (hot or cold) and Cups are very sensitive to both pressures & temperatures. Sounds like you were overheating them from the start. On track the correct tyre pressure for Michelin Cups is 26 psi (cold) and should hover around low 30's psi hot unless there's something amiss. The 2012 DOT is perfectly acceptable as the rubber life span of these tyres is around 5-6 years (if they were heat cycled correctly from the start) although they don't phisicaly tend to last that long if you track your car frequently __________________ UK CSL No.020 ... after 7 years of ownership I've now SOLD it !!! Last edited by mattCSLnut; 04-08-2015 at 03:23 PM.

04-08-2015, 09:25 AM	#3
Rick H S5, Sport Off, DSC M-track Join Date: Oct 2012 Location: The North West Posts: 801 Casino cash: $12295	I bought a similar set from Tyreleader. I'm not really any good as a judge, but my car was recently driven by a racing driver on Anglesey and he remarked specifically on the huge amount of grip the car had. You got 5 trackdays from a set of Cups ? ? ? ? ? ? Is that normal ? ? ? ?

04-08-2015, 11:26 AM	#4
khooni S5 - Full Throttle Join Date: Aug 2012 Location: east london Posts: 309 Casino cash: $3592	tyre pessure is 35psi all round. suspension is kw clubsport (gen 1) non adjustable track geometry setup by simpson motorsport none of the above had changed. I just went on a track day at Snetterton 2 weeks ago and the grip was fantastic. Yes.. 5 trackdays on a set of cups. Yes the previous set had a huge amount of grip as well. Maybe this is a 1-off... but.. wtf.

04-08-2015, 04:18 PM	#7
khooni S5 - Full Throttle Join Date: Aug 2012 Location: east london Posts: 309 Casino cash: $3592	Hi Matt, I accept that the pressures could be a bit high. What it doesn't account for is consistency of the track and why it degrades evenly through out the day. It should be a 1-time.. oh that's bad and remain the same. But it doesn't, it just constantly goes down. NB I have tried these 35 psi HOT temps for 8 trackdays now and have never felt the tyres going off the way they are doing now. Gradually rubbing off performance the entire day such that at the end, it was basically understeering everywhere. I'm going to try again and see if i can get new cups on soon and report back.

04-08-2015, 11:38 AM	#8
billyboysm3 CSL Register Uber-poster! Join Date: May 2011 Posts: 3,001 Casino cash: $25206	And how many laps per session,

04-08-2015, 11:49 AM	#9
khooni S5 - Full Throttle Join Date: Aug 2012 Location: east london Posts: 309 Casino cash: $3592	5 laps. 22deg ambient temperature. It just wasn't turning in and when I put the power down it just wanted to understeer. My car is setup to understeer so I can brake as late as possible and trail. It's gives me great confidence in that the tail won't snap on me and just gives me the extra turn in required when trailing the brakes. Yesterday it was just a pig, and when i gave up setting times and wanted to hoon, I discovered that because my front end doesn't grip, I have difficulty booting the tail out. The symptoms are that the tyres are fooked. I'm buying a new set now. ............. but i'd appreciate if anyone thinks it could be something else.. oh, 1 more thing. that bonnet is really irritating me... I'm gonna tape it shut with masking tape.... is it ok to use masking tape on the paintwork?

04-08-2015, 12:02 PM	#10
billyboysm3 CSL Register Uber-poster! Join Date: May 2011 Posts: 3,001 Casino cash: $25206	Grant went to Silverstone a few weeks ago and that had poor grip, Id say tyre pressures to hot and track had poor rubber laid down on it.