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Super Mod,
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Discussion Starter #1
I need help in determining if the tire wear seen in the picture is due to the tire ending its life or something in the suspension. The tire was giving me issues on my last track day.

I picked up the tires as race take offs from Nate Kern (1 race / 15 laps) and have done 4 track days on them since then. This is the first time on these tires (Super Corsa Pros Soft/Medium) so I'm trying to get an understanding of them.

I did make some changes to the bike which included adjusting the swingarm pivot with the eccentrics in the +2mm position. Ride height was lowered so overall ride height did not change. I did make a minor change to the damping (compression) but it was 1 click to make it 'softer'. I do not use tire warmers but do not push the bike during the first lap or so.

So do you think it's just the tire or is something else at play?

 

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Upside Down Super Mod,
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:dunno Could be suspension, could be you, could be the track. Did it only do it on the last track day and none of the other 3? No signs of that sort of wear when you got them? Looks like it might have been a bit cold.

I'm just digging up some pics of the last 3 rears I ran. I'd wear rubber off them but not tear them. I'd run between 31 - 33 psi only a tad more than your 30, but might have been on warmer tarmac too.

Supercorsa SC1 120/70 Front
Supercorsa SC2 190/55 Rear
 

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Upside Down Super Mod,
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I probably don't push my street bikes on the track as hard as you push your track bike. Another difference is I fit new tyres before each track day, so these pics are on tyres that have done less than 200km / 125 miles. The GSXR one might only be a session or two old. (And I'm a shit photographer.)

Phillip Island is full of lefts. (CFB1)

SC2 - TLS Sep 05 stripped rubber off it but not really tear it up.


SC2 - TLS Feb 06 one of the best track days I ever had. Even wear.


SC2 - GSXR Sep 06 Took it pretty easy, but I wasn't all that shy on the exits. Similar wear to the TLS.
 

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Super Mod,
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Discussion Starter #4
Nope, this was the first time they wore like this and the second time on this particular track with them. It was quite a bit cooler than before (over all temp) on this day. I originally throught it was due to cold tearing but thought I'd get a second opinion. :)
 

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Upside Down Super Mod,
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Probably cold. Better wait for a 3rd, 4th, 5th and 6th opinion though :laugh
 

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I had similar wear to what is seen on the chain side of your rear.Mine was so bad the tyre was concave on one side..That was 1 track day (100miles) ...I put it down to the fact I was not going in to the corners as hard as I could have been which meant I was able to accelerate harder than I should have (give it big handfulls of throttle) on the exits and was tearing up the tyre. the rear was sliding all over the place by lunchtime but with a little finess on the throttle I was maintaining lap times throughout the afternoon..I think it was mainly down to my poor throttle control and lack of realisation of what the tyres go through that lead to my wear..

I was running about 33 psi front and rear it was about 20-23 deg c air temp and sunny.I was by no means fast but was dragging the pegs every lap....

i would like to see if this is suspension related or just me.
 

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First of all: This is not bad after 4 track days. A rear SC2 usually lasts maximum 3-4 days on my TLS.

There are two and a half reasons for the torn tyre:

1) too cold ambient temperature. I made the experience that the rear Supercorsa Pro SC wear like this with ambient temperatures below 25° Celsius. Solution is to raise the cold tyre pressure about 5 to 10%. (2.0 to 2.1 bar instead of the recommended 1.9).
Btw: Pirelli compound vs ambient temperature: Choose a HARD compound for low ambient temperatues. The SC3 rear is the only tyre that works below 20° C. Don't ask me why, but that's how it is!!!

2) too much mechanical grip. Solution is to lower the rear / to change the swingarm pivot accordingly.

2.5) Your driving too slow into corners and thus accelerate too much at the exit ;)

I love these tyres :)

Here's a photo of a Supercorsa Pro SC2 take-off that I found in my garage:

I bought it used from Tom$lick and used it for another four days: Two days Misano and two days Spa Francorchamps. This one is really trash on the left side, right side is almost over (tyre is upside down). Middle would last for another 2000km of highway :)

PS: And think about tyre warmers. It's worth the money IMO.

Greetings
Rufer
 

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When my UK Dunlop went off it started with cold tearing like that. I did it on a 104 degree day and it was shit after it started.

Right side = good grip. Left side = over!:coocoo

 

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I'd say if you've got four track days out of a set of take offs, you're doing well.
Looks a little like cold tear, but being through that many heat cycles I'd say it's just done
 

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Mine still looks like that now after my last track day, with a nice Blue colouration on the outside too, interesting theory about the coldness though, how do folk learn these things:banghead
 

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Posh Johnny said:
how do folk learn these things:banghead
In spring a rear lasted max. 1.5 track days on my TLS
--> Experience :O

Greetings
Rufer
 

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Super Mod,
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Discussion Starter #14
A couple of you suggested going in to slow then powering out too hard. At first I thought that was a little preposterous but then I got to thinking about how I spent the first part of that track day...

I run with quite a bit of corner speed, a lot more than others at times (in the intermediate group anyway). Since I spent the morning in the that group I had to restrict passing to the outside. Since this is also only a track day and I'm not there to impress anyone so I wait until after the apex to make that pass. So this would mean I'm on the brake more going in then hard on the gas on the exit as suggested. When I was in the advanced group things were rolling smoothly but by then I was fighting grip issues.

With all that was suggested and some pondering I think it may have been a little of everything.
1. Tires near end-of-life
2. Colder temp
3. Slow in / Hard out

I spent today swapping out my rims back to the white ones so I can get new tires mounted to them when I'm at the track on Monday. Tire warmers are high on the 'get' list for next year. :)
 

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Doesn't look too bad. I'd be tempted to drop 1-2 psi on the back and see how it works. Tracks and days at the same track are different, along with the tires and compounds. The place that I always start is at the tire pressures.
 

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mine was looking like that but finally ended up like this after a few days at the nurburgring, i was running it about 33 psi, felt it squirming about a bit but still gripped fairly well,
 

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I think it is because U are to slow :dunno
 

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Come over to Bridgestone. :) I've got a set(BT002 medium) with two days on them if you'd like to sample. $50.00 + 15.00 to ship. 190/55 rear.

I'd be curious to hear your comparison.



I added the Eccentrics to my K5 and the tire wear has been very good even though I've heard they will accelerate the wear in the +2mm position.
 

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well I haven't seen nate kern race but to finish where he does on a bmw I know he is not leaving any time on the track, so out of the gate those tires have a pretty good heat cycle on them, and from the heaviest racebike in the world at that. And then 4 track days on a TL? They could look a lot worse than they do.
I have found that on my SV650 racebike that the pirellis will show very little wear until they are about cycled out, and then they will develop that torn up strip in a relatively short time, no matter how I ride or how suspension is working. Now if you are getting that wear on new tires you need to speed up your damping, but it is impossible to second guess suspension problems on a tire that is running past its service life.
 
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