Tyre Philosophy
 

Hope the title makes the thread sound very deep.

I'm a bit obsessed with tyres and tyre pressure these days I don't know if Im just zoning in on it or it actually really matters but this week I think it does matter.

I bought pair of HALO Knobblers a while ago, 2.2, for XC and a lot of people were commenting on how big and arkward they were. They were right too, these tyres have big grooves etc and really stuck to the road, you can actually hear the back wheel peeling off the road as you cycle. So, very grippy which was great off road and also the tyres were so tough I never got a puncture. (Im talking tyres with tubes here not tubeless). However, I reckon they were slowing me down a lot on fire roads etc. They're big tyres!

I switched to Nobbly Nics recently to do a couple of faster races. Not as grippy and on a very mixed terrain race I got a couple of punctures.

The past few days I've been riding some "downhill" stuff so I put the big tyres back on. But I can't make up my mind about how much pressure. I have them very hard. I know they say you shouldn't have tyres too hard for grip. But Ireland is all muck and roots. So, for muck and roots do you really want hard tyres to roll over things? or is it going to make you slide too much on slippery surfaces?!

This is a bit involved I know. Normally, I'd just say ride your bike!

Are tyres on downhill bikes usually kept very hard?

Keep them lower PSI for the traction and to absorb some of the shock from the roots.

Don't know what pressure that your running now but try something in 30 pound range. Less air pressure lets the tire morph to the terrain and not skip off of it but the lower the pressure the more chance of flatting you have.

those are some serious looking knobbies...

I like!!!

I run my tires with the lowest pressure possible. Traction is good.

Lower PSI here as well.

Also keep in mind, when we say lower, it means relative to our weights. I'm a heavier guy, so I run my tires at a pressure that would probably be very high for other people, but right for me. Too low, and it becomes easy to pinch flat.