Hey, what´s up?

I use a Michelin trial compettion fron tyre with still 1/5" (5mm) knobbles, I´m not sure if is just paranoia but I have the "feeling" that I don´t have too much grip.

I set the pressure at 6.5 psi

How do you know when a tyre is over and need to be replaced? what´s the limit?

I ride mostly over hard terrain, wet rocks with lots of stones, no mud. Would do you suggest me to keep with Michelin or better try Dunlop?

Cheers

Drop the pressure to 4 psi then also try 3.5 psi then see how you go. The tyre is shot when the leading edge of the knobbles are rounded not square.

5MM Knobbles!!!!!!!!!!

it was knackered about 6 months ago.

4 psi is a starting pressure. Bit less for mud and perhaps a bit more when dry and sunny on rocks.

If you only have 5 mm of tread then it worn out. I rarely take more than a couple of mm off the height of the tread. Its the squareness of the tread that grips. Rub your hand over the tread of a new tyre and a used tyre to feel the difference.

If you are riding dry rock a tire will last until it can`t hold air any more! But at 6 psi you are not getting all the grip possible.

6.5psi is too much...? but, i'm talking about the Front tyre..

5 psi is ok for the front in rocky conditions, although you need to be careful, you don't realise how bad tyres are until you put new ones on !!