How to tell if a tyre is past its best

[MaxCannon]

I have a Conti Sport Attack on the Front and a Metzler M3 on the Rear.
Part way through turn 4 at Hampton downs the bike suddenly lowsides.
No warning at all. Up to that point (this was the 5th session of the day) the bike has been feeling excellent.
I still don't know why I ended up on my ass in the middle of the track but I'm wondering if I could have cooked the tyres.
Can a tyre shop do any checks on the rubber - it still feels soft to me but I'm not a tyre expert.
The track was scorching hot at the time and I tend to work the tyres quite hard - is it possible that the sticky hot track has overheated the rubber ?
Just before the session I'd set 31 PSI cold front and rear.

[AllanB]

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The track was scorching hot at the time and I tend to work the tyres quite hard

Sorry to hear of the off. I take it it slid out from under you?

I'm figuring you found the limits of your available traction at that given point for that given speed. If the tyres had gone off they would be feeling weird prior to the off at earlier corners, squirming and pissing you off.

The best bet is to delete this thread and post a new one called something like "Piece of Shit Conti' (or M3) - blame the tyres. It won't help your racing but it will be very entertaining!

[yachtie10]

I saw you come off but unfortunately not the leadup
I got the impression you were going wider (maybe a bit quicker)than usual and leaned in extra to compensate ( like I said I did not see it all but just my impression)
Did you ask Ash afterwards (I think he was the one who stopped to help) I think he or Darren maybe could have helped by looking at the tyres.

You did move well after the off

[MaxCannon]

Cheers Dave - I didn't want to get run over like the poor guy from the earlier session. Hope he's alright.
As soon as I hit the ground I was trying to run towards the sandtrap.
Then I had to run back onto the track and pickup the bike.
I think you may be on the money. I'd thought I hadn't changed my line but with the initial shock wearing off the more I think about it maybe I did just get too aggressive.
The tyres (to my uneducates eye) look fine. Might stop in to KTL and as them to have a look just to be sure.
I talked to Ash when I went back to the pits. His words "sometimes - shit happens".

Yeah Allan - it was just a sudden straight out from under me slide. Completely unexpected.
The look on my face must have been priceless- WTF ! - I'm on the ground.
Didn't notice any odd behaviour earlier and turn four is one of the slowest on the track.
Into turn 6 I'd run in hot a couple of times and the bike would drift wide as I ran out of grip.

Anyhow - no harm no foul. I'm fine, the bike is fine (needs another head guard but those BMWs sure do crash well).

[sinfull]

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Anyhow - no harm no foul. I'm fine, the bike is fine (needs another head guard but those BMWs sure do crash well).
Don't like the miss match of tyres, say there lies half your problem as the M3 would handle a workout (possibly) better than the sport attack !
2nd point i'd make is that i have learnt that road tyres (my whoops was on a road attack but close yeah) aint designed to get as hot as they would have been and when overheated will lose grip (whereas track designed tyres get stickier), so i'm picking the rear was gripping when the front had lost its grip and just washed out on ya !

[Mishy]

Don't like the miss match of tyres, say there lies half your problem as the M3 would handle a workout (possibly) better than the sport attack !
2nd point i'd make is that i have learnt that road tyres (my whoops was on a road attack but close yeah) aint designed to get as hot as they would have been and when overheated will lose grip (whereas track designed tyres get stickier), so i'm picking the rear was gripping when the front had lost its grip and just washed out on ya !

Some of what you say is quite correct, and it's cerainly possible to get a road tyre so hot that it "smears" and looses a little traction.
Generally this give long predictable pushes on a front tyre, and is not normally associated with sudden unpredictable loss of traction. That's normally low temp related, or simply one of those "shit happened" crashes.
As far as Sport Attack goes, I'm afraid you really don't understand what that tyre is capable of., and it's not close to Road Attack at all.

[sinfull]

Some of what you say is quite correct, and it's cerainly possible to get a road tyre so hot that it "smears" and looses a little traction.
Generally this give long predictable pushes on a front tyre, and is not normally associated with sudden unpredictable loss of traction. That's normally low temp related, or simply one of those "shit happened" crashes.
As far as Sport Attack goes, I'm afraid you really don't understand what that tyre is capable of., and it's not close to Road Attack at all.
Still at the counter there Mishy haha
I do like the sport attacks actually, done a couple of sets on the speed triple and a set of road attacks and i think they're (sport attack) wicked road tyres and i'm hard on em !
My whoops on the road attack was a rear slide (had me kissing the dash in a learning curve not to decellerate completely), 5th or 6th session, cocky as, on a hot sticky trackday ! Went there with the thought why take a near new tyre off the bike, may as well use it up in a few practise days prior to my first race meet ! First mistake !

My main point was the miss match !
When i posted that, i was thinkin he'd probably replaced the rear tyre and went for the M3 for whatever reason and there he was on a track, 5th session, with a front thats done god knows what milage and a rear thats probably in better nick ! Sport attacks have grip yeah but M3 are a good tyre also (newer too perhaps ?)
I'd be interested to know what lap he found himself on his arse at turn 4 ! First lap ? Would see him out there feeling confident after a good day, cold rubber, missmatched road tyres and prob a rear tyre that has more grip ! And just to top it off suspension that possibly aint cut out for the (as he put it) aggressive track riding he was doing !
Hell who knows, shit does happen lol

[MaxCannon]

Some good healthy discussion on tyres - I love it.

The M3 on the back was new at the start of December - the Sport attack on the front was new at the end of Decmeber - probably about 800km between them.
When I got the bike there was an M1 on the front - the original 2006 M1 which was perished and downright dangerous in the wet.
I wanted another M3 but just after christmas there were none to be had and I really needed a new tyre.

It was the the 7th or 8th lap on the 5th session of the day - tyre was definetely not cold.

After chatting to a few people my best guess is that I have suspension at the front setup too soft and with the increased speed I'd started carrying the rear which is set correctly for my weight held longer than the front.
It's also quite possible I wasn't hanging off as much as I had been - hot day, lots of laps, started getting lazy.

[Mishy]

It's also quite possible I wasn't hanging off as much as I had been - hot day, lots of laps, started getting lazy.

I'm with ya there !
The suspension thing is a real possibility too.
Too soft, and blowing through too much of it's stroke early would load the front heavily, and can easily account for a front end loss.
As usual with race track stuff, it can be several things put together that end up with you having a bum scraping moment :)

[Mishy]

[QUOTE=MaxCannon;1129674075]
The M3 on the back was new at the start of December - the Sport attack on the front was new at the end of Decmeber - probably about 800km between them.
When I got the bike there was an M1 on the front - the original 2006 M1 which was perished and downright dangerous in the wet.
I wanted another M3 but just after christmas there were none to be had and I really needed a new tyre.
QUOTE]

FYI - the M3 and Sport Attack are very mutch equivalent tyres, and there is no real likelyhood of the M3 dominating the other because it's "more grippy". Very similar tyres designed for the same market, and a reasonable match on a bike.