Tyre Pressures

[beefcake]

I would like to hear what sort of pressures people are running in their tyres for XC riding. I have got 26X2.0" tyres and I wouldn't have a clue where to start (in terms of pressures). Some people say over pressurize, some people say otherwise.

Any ideas? I am generally on gravely/rocky terrain, and my tyres aren't tubeless.

[orchie]

By gravelly you mean loose rocks? I'd start around 35-40psi. Going harder will mean that you have less grip, softer more chance of flatting.

Grant

[...jim]

By default (non-UST tyres + tube on XC rim) I start with 35psi in each end, regardless of tyre.

Then I'll add or decrease depending on what tyre I'm running or the terrain/conditions. But 90% of the time it's 35 all round - either because that's what I get used to, or I have a pea-sized brain and can't remember variations.

[porter_111]

I have been riding a dually for over a year now and have found that running higher pressures is better. I remember as a kid what a difference riding my BMX with its tyres pumped up hard on the road made (so much less rolling resistance).

I use that idea in the bush now. It makes a lot less resistance on the fire trails, the dual suspension soaks up the rough stuff, and I don't sacrifice to much cornering grip. I agree that there is less contact surface with high PSI, but it seems minimal.

Of course I'm not talking about pumping the tyres up to 100psi, but try out a harder pressure. It works for me.

[AUDIOZ]

I have been riding a dually for over a year now and have found that running higher pressures is better. I remember as a kid what a difference riding my BMX with its tyres pumped up hard on the road made (so much less rolling resistance).

I use that idea in the bush now. It makes a lot less resistance on the fire trails, the dual suspension soaks up the rough stuff, and I don't sacrifice to much cornering grip. I agree that there is less contact surface with high PSI, but it seems minimal.

Of course I'm not talking about pumping the tyres up to 100psi, but try out a harder pressure. It works for me.

High pressures work for me too. I run 48 psi front and rear on my Top Fuel Dualie - and set the suspension a tad softer to compensate and I find it has made me heaps faster on the trails with very little cornering compromise. I run tubeless however. See Spec. and pics here. http://forums.farkin.net/showthread.php?t=38402

[Gripper]

Generally, these PSI's are my starting points for XC/trailriding on 1.9-2.1 tyres.

Front: 30 to 40
Rear: 35 to 45

Most often it's 35 front/40 rear

Suspension is set at med>hard on the rear and med>soft upfront

My dualie trailbike weighs 14kg ish, me about 75kg ish

[barefootbushman]

I hav a hardtail and ride mostly on sand so have hard tyre pressure all round (50psi). But when i do other trails and forget to let the pressure down i get the madest arm pump.

[aaron01]

Have a look on your sidewall of the tyre most of them will give a recommended range if you can't find the info on your tyres maybe try the manufacturers website. The upmost rating is usually for on the road & the lower most rating is for more loose/rocky surfaces. I find somewhere in between works, as most others are saying about 30-40psi is a safe bet for general use, when I'm racing though I always tend to go about 5psi higher just to help with the rolling resistance & make life a little easier on the climbs. Just to put it into perspective though my road bike runs about 90-100psi specialised tri sports while my single speed will run about 40-55psi (commuting) 26 x 2.0 maxxis/ 26 x 2.3 continentals pending my mood & my duel sus race bike runs about 35-40psi 26 x 2.0 maxxis larsen TT or 26 x 2.1 maxxis larsen TT pending track conditions & type.
Its a bit like anything with cycling trial & error, good luck hope all works out for you.

[demo man]

^^

haha, don't worry about what it says on the sidewalls! it says on Minion DH tyres 35psi minimum, yet i never run more than 32 while on trails (and i have gone as low as 16psi without flating).

just run then harder for smother tracks, softer for bumpier ones. simple.

[barefootbushman]

16psi is suicide

[demo man]

for XC it certainly is!

but i was DHing at the time...still really bad though - i didn't run it that low on prupose - it was just out of laziness or something.

[Dumbellina]

Your body mass also affects the tyre pressure of choice.

I weigh about 110 kg and ride hardtails (mostly), so I cannot go below 35 psi whether or not I run UST tubeless. If I do the tyre squirms under cornering load leading to premature tearing of sidewalls and the tyre folds on impacts with square edged rocks damaging my rims. Also at low pressure the squirming tyre is just plain scary on hardpack corners, especially as knobs start twisting.

My general range is 35 - 40 psi regardless of tyre or terrain. Also any higher and the ride is uncomfortable.

[demo man]

i weigh about 105-110 and i ran 16psi fine! but i'm a dick like that.

it was only once and it was an accident.