A question re. motorcycle tyres

I crashed on the 4th of October; felt like the front end gave way on a bend, so ended up belly sliding along the road at 60; breaking a finger in the process and causing some damage to the bike.

At the time I didn’t notice anything on the road that could have cause me to lose grip, I have taken this bend 100s of times before at the same speed and lean angle with no problems whatsoever, only that day the bike went down. Initially I thought that a drop in ambient temperature was to blame, as that day I did actually feel the cold on my chest, so wrote it off as a mistake on my part (thankfully I got to walk away from this one!).

I used the bike yesterday and when wheeling it out I noticed that the rear tyre is blue towards the outer right edge, the front too – I have heard about this sort of thing before, but don’t fully understand it, so I had a quick Google this morning and read a couple of forum posts about it and it seems that this could/may be a factor in me coming off; as the bluing leads to a total loss of grip!

I’ve had the tyres fitted for a couple of thousand miles now, they are Pirelli Diablo Corsa 3s, I noticed about a thousand miles back that you could clearly see the compound change from hard/medium in the middle to the soft outer edges, which I don’t recall seeing on my last set on my old bike, so whether this is an issue as well, who knows?

I guess my question is, as the tyres are pretty new and have only been used on the road, if they have failed this early and contributed to my crash, would I have grounds to complain to Pirelli and maybe get something towards the cost of repairs/a free set of replacement tyres?

Also, what is the general consensus on tyres going blue?

There are two reasons I know of (and experienced) where tyres go blue..

1. If unused, tyres do go 'blue', I've had this on all my tyres after a winter lay-up, but they blue tends to disappear if you gently re-scrub them in, and they seem fine again.
2. Large heat cycles - e.g. if underinflated and the tyre gets too hot then cools and you do the same again they can go a bit blue, but usually you can see the tyre also starting to blister badly..

From what you describe, it could be they where underinflated for a period of time, as it would really start to stress the softer rubber, which would deteriorate first?

Just a thought..

Hey Demon, thanks for the reply

The bike has been constantly used prior to coming off, and the pressures checked before I went out, they never lost a single PSI, so I am pretty confident that this wasn’t an issue.

You point about them being unused is interesting though, as prior to yesterday I had not ridden the bike since the crash, so that was a month laid up in the garden; maybe they went blue during this period of inactivity?

Now that I think about it, I am unsure if they were blue at the side of the road; all I can recall seeing was the scrape where they had slid down the road, but I had a lot of things going through my head at that point, so I may have not seen the bluing

I think my main worry now is whether they will be safe – it’s going to be quite some time before I’ll be using that patch of the tyre again, but when I do, the last thing I want is for them to give up the ghost again! Will roughing them up with sand paper do the trick?

You can always see the change between the compounds on the Corsa 3's
As for blueing as said above either been sitting outside for years or heat cycles, and its unusual to see a big obvious blueing from daily riding unless you like doing burnouts
Was most probably either a greasy road if the tyres have been fine since?

And yes probably being sat in the garden now its getting colder will cause the tyres to go blue, the supercorsa's on my sv thats been sat for a year in the back yard are lovely and blue!

Chuffed, well I’m satisfied that that didn’t cause the crash then, must just be the sitting idle waiting for repair day (next week!) that has blued them up – I take it it’ll be ok to scrub them down with something abrasive then?

Scort said:

I take it it’ll be ok to scrub them down with something abrasive then?

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No you should never do that. Just ride them like a set of new tyres and they will get up to temperature and regain their grip.

Finglonga said:

No you should never do that.

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Excuse my ignorance, not wishing to argue or anything though, but why is this?

Scort said:

Excuse my ignorance, not wishing to argue or anything though, but why is this?

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Will only heat up the top layer of rubber and it will do it too quickly and unevenly..

warming up the tyre gradually (like you would with general riding) means the heat cycle is slower and more even.