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No change in tyres performance

Is this some weird bug ? Or something that's already known?
I have noticed that tyres have no change in performance when below 40%  I would expect a huge reduction in lap times if the tyres were burning out...I find its the same on any tyre.

That's true for soft and supersoft. Medium tyres seem to drop around 50% due to temperatures in northern hemisphere. Hard tyres are a good choice if you like to finish last and I won't check it.

I think you are right anyway.

It's not a bug, do you analized data to support what you are saying? I guess not if your level 8 account is your main account you need more experience.

There is a drop in performance but it's just too poor to notice in combination of the fact that the car is way lighter (so faster) due to fuel consumption.

If you lies your expectations on real f1 (that is wrong because this is a simulation), when refuel were admit drivers got fastest laps always at the end of each stint where tyre was consumed and fuel load was minimal.

What i'm saying it's that this game need a full balance work looking at the big picture, not just tyre. 

Since the last tyre update the wear rate has increased but performance lasts longer, they now can be run to lower wear percentages. There is still a drop off but it's not as noticeable as before, you will during races have to see how far you can run them, too much and lap times will tumble 1-2 secs per lap.

Yeah it's somewhere between 25-32% now and you will suddenly notice a drop mid lap if you have two cars and one has just a lap fresher tyres. You can lose 0.5s a sector at that point. They will start to lose time from around 55% but the time lost is more than made up for the time gained in fuel loss at this point.

You just have to record the data you see as you race and gradually build up a picture of the maximum life you have for each track on each tyre.