Reading your tyre wear

sfcpiet said:
Not entirely true.

Road use gets tyre temps nowhere close to what would be attained on a forcefull track run.

If the bike has the power and the rider the speed on the track, the tyre will quickly reach a proper operating temperature and pressure will rise to a "normal" level if it has been reduced beforehand.  If not, pressure will rise to abnormal heights, causing all sorts of havok, especially playing tricks on the suspension.

When riding Spa on the 3C in warm to hot conditions, rear pressure was set at around 2.0-2.2bar in the 150/70 BT012S, measuring imediately after leaving the track showed a very normal and healthy 2.7-2.8bar, the pressure I would normally use on the road.  Tyre performance was perfect, as expected.  Wet conditions called for slightly raised pressures as not enough heat could be generated.  I also had the oppurtunity to run a set of slicks on the old banger, pressures needed to be reduced even further.  The performance these things offer cannot be described, it needs to be experienced! :D

Hard to overheat tyres at the pace our bikes are capable of, slight blueing at the edges can be considered quite normal after temps have returned to ambient.  Have yet to see a Lav that has managed to blister its tyres, provided they were run at appropriate pressures.

Badly chewed up tyres after track runs are not always the result of incorrect pressures, properly working suspensions go a long way to help reduce tyre wear.

piet
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My experiences were based on my Aprilia RSV and as rule-of-thumb estimate I?ve transferred this (maybe to much) in general. For example, the frequently
driven Pilot Power gets very quickly out of its temperature range when it is used on a racetrack:
49157506152_2e3aaaeca7_z.jpg

???

It also makes a difference whether you drive in Spa or Oschersleben, in Spa I measured a lower delta between cold and warm tires, obviously because
of the relatively long track in combination with the two high-speed sections.

As for the use of slicks and rain tires - yes, they make a big difference! I'll never forget the first full rain workout in Spa, when I decided to invest in rain
tires, unbelievable what's possible with them.



Tippie said:
And what is a pure racing tyre? My CBR600 track bike uses tyres approved for supersport which are dot road tyres and recommended pressures for the track are 1.4rear/2.4front kpa, they work brilliantly. On the road they would need heaps more in the rear, and many people use these tyres on the road. My race SF on Conti attack cr tyres which are also dot road tyres have under 30psi front and rear, had I used high pressures, even higher than road as you suggest I would get absolutely nowhere. Vince's experience is very common, I thought I was a real hero first time I road at a racetrack, sliding the back out and going nowhere with cold road pressures.
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These "Hypersport" tires you mention are actually road-legal racing tires. They should not be the first choice when driving on country roads or even in
the wet though.

Next, I want to put Contis on my Laverda, only that I do not intend to drive on the racetrack with her (in fact my suspension is the next big building site
I've to put my attention to).

In general, I have no experience on the racetrack with classic motorcycles, or with the tire dimensions used on classic bikes. I think that you have much
more idea about that ...


Cheers
Jo

 
Jo, you are right they are road legal race tyres (basically slicks with some tread to be allowed in supersport racing). Yes they are lethal in the wet and shit unless in their operating temperature. It is a mistake for people to think that because they are a sticky race tyre they will be good for riding fast on the road, they can't get up to temperature.
 
Tippie said:
I wouldn't complain about the look of that rear slick. What do you see wrong with it Carlo?
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When we see comet tails on the wear holes trailing backwards it indicate not enough rebound (rebound too slow), so tyre staying down too long. You can ride all day like it but depending on your track you might see better tyre wear and improved handling characteristics with some more rebound (wind out a couple of clicks and see what happens).
 
cbertozz said:
it indicate not enough rebound (rebound too slow)
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Those two statements are opposites, Carlo. Not enough rebound = retracts/rebounds too fast (bounces). Too slow (= too much) rebound can be blamed if the rear continues to sink over a series of short sharp bumps or corrugations.
 
In the dirtbike world that's called packing down, the shock gets another hit before its done its job on the first bump and this repeats till the shock bottoms and stays bottomed. That's why videoing or watching the bike from afar is a great way to see what's happening, it's easy to get it wrong just by your feel on the bike. Especially with short road bike suspension travel.
 
Piranha Brother 2 said:
Those two statements are opposites, Carlo. Not enough rebound = retracts/rebounds too fast (bounces). Too slow (= too much) rebound can be blamed if the rear continues to sink over a series of short sharp bumps or corrugations.
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Too much rebound damping - too slow
Too much rebound - too fast.

Fully closed rebound circuit = maximum rebound damping = slow

Fully open rebound circuit = maximum rebound = fast

It?s all semantics
 
I installed recently these rubbers:

IMG_7594.jpg


IMG_7589.jpg


IMG_7588.jpg


then I once drove around the cow pasture to control the fence.

Back home I checked the tire wear ----- but what the hell? Look at this:

IMG_7582.jpg


IMG_7571.jpg


IMG_7568.jpg



Can someone read that tyre wear?


Cheers, Jens  ;)
 
You really destroyed those K81s Jens. My Contis wear really well. This is after lapping just outside the class record, new rear damper units, fitted them as they came from Maxton. This tyres is three race meetings old. The tyres looked the same with the old Ohlins too. Used to chew the shit out of Avons but still always got a season out of them at least.
 

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Jens said:
I installed recently these rubbers:
.
.
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then I once drove around the cow pasture to control the fence.

.
.
.
Back home I checked the tire wear ----- but what the hell? Look at this:
.
.
.
Can someone read that tyre wear?


Cheers, Jens  ;)
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Jens, please name the track you rode on, as it seems to form a Conti out of a Dunlopp tire...  :o
 
Am I the only one who saw the humour in Jen's post?? Apart from the K81 joke, that destroyed tyre shows something must have been a tad wrong in setup!!
 
Piranha Brother 2 said:
Am I the only one who saw the humour in Jen's post?? Apart from the K81 joke, that destroyed tyre shows something must have been a tad wrong in setup!!
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If you think so, I think you missed the humour in the other posts (including mine...)  :D
 
the real humour is that he is going to use.... what..... TT100's in the current time???
ha ha ha

wait till you try them Jens, then report back.
CLEM
(ps is that Kronberg by any chance?)
 
Wouldn't it be interesting if some enterprising individual took a bunch of tyre pictures on Saturday's ride of all the Laverdas there and we had a guessing game as to who has good and bad issues?
 
the real humour is that he is going to use.... what..... TT100's in the current time???
ha ha ha

wait till you try them Jens, then report back.
CLEM
(ps is that Kronberg by any chance?)
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Clem,

You hit the nail on the head :)

To be honest, as you could see my story was not entirely true...

The Conti Road Attack on the photos served for many rounds on race track like Spa, Oschersleben, Spreewaldring (Berlin), Hockenheim, Schleizer Dreieck, Adria Track and also at tours around Breganze. So much fun, no issues. I used them longer than you should do. The wear pattern was always not too bad.

So I needed for sure new ones and at the same time got the offer to test for free, how the TT100 in the new version "GP" behave. The 100/90-18 version  of the Dunlop TT100 GP was new in 2019.

Did mount them, took the photos and was quite unsure if I should really use them even on the public road. The classic look ... did not look adequate for my eyes.

I was with them about 200 km on the street. Surprisingly a really good feeling. I would say, it is possible to use them not only to make a Laverda look classic but also to use them for a ride.

After that short intermezzo I immediately switched to the Road Attack CR 3 and I am looking forward to the 2020 season.

Dunlop TT100 GP: fun
Conti Road Attack CR: serious fun 

Jens
 
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