I guess on really hardpack stuff and rocks, then yes, a soft tyre is good. Clearly soft will grip on asphalt better due to the larger contact patch and the way it will shape to the road. Hardpack is going to be similar.
But... if you're riding on a loose surface I feel a hard compound is going to work better, it will cut through the stuff on top and bite into the firmer terrain underneath. I'm not talking about muddy conditions here, just *any* trail which has a bit of dust on it.
Imagine you had a really really really soft tyre compound (think marshmallow-soft), and now imagine that tyre going around a corner which whilst not what you'd call "loose" has some surface dust as the top layer.
If the compound is soft enough the tyre blocks will just deform into a flat surface and be pressing down on all of the loose stuff - this will not give optimum grip since the loose dirt will slide.
Now imagine your favourite tyre tread made out of something totally rigid - metal. It's not going to be a comfortable ride, but think how well that's going to bite through the dust and into the hard terrain udnerneath - it really would be like cornering on rails.
Obviously these are extremes, I just find it easier to think something through if you take the extreme ideas and work back from there.
Are we in fact just being sold all these soft compound tyres because of a placebo effect - after all, it's in the tyre company's interests to sell us the softest tyre they can...
But... if you're riding on a loose surface I feel a hard compound is going to work better, it will cut through the stuff on top and bite into the firmer terrain underneath. I'm not talking about muddy conditions here, just *any* trail which has a bit of dust on it.
Imagine you had a really really really soft tyre compound (think marshmallow-soft), and now imagine that tyre going around a corner which whilst not what you'd call "loose" has some surface dust as the top layer.
If the compound is soft enough the tyre blocks will just deform into a flat surface and be pressing down on all of the loose stuff - this will not give optimum grip since the loose dirt will slide.
Now imagine your favourite tyre tread made out of something totally rigid - metal. It's not going to be a comfortable ride, but think how well that's going to bite through the dust and into the hard terrain udnerneath - it really would be like cornering on rails.
Obviously these are extremes, I just find it easier to think something through if you take the extreme ideas and work back from there.
Are we in fact just being sold all these soft compound tyres because of a placebo effect - after all, it's in the tyre company's interests to sell us the softest tyre they can...