Tyre Pressures

I know this is how long is a piece of string but whats the min pressure that i can go down to without getting pinch flats.

29er wheels RR and NN tyres 2.25 and weight 90kgs

Im running 40psi at moment. Also not really wanting to knacker the rims either.

wow, 40psi sounds like tons. I’ve got around 18psi in my rear and 15 up front.

min pressure that i can go down to without getting pinch flats.

depends where and how you ride. I imagine you could probably get away with about 5psi on the pavement…

add more for rocky areas, add more again for riding like sack of spuds.

Way lower.

Try 27-30psi and feel the grip.

PaulD

Very helpfull thanks.

Lets assume im not riding on top of snooker tables.

Can people really tell the difference between 3-4 psi?

Pump it up till it’s hard then deflate till you can poke the centre a bit with your finger. Job done!

Too many factors, one can only find out by trial and error:

How fast you go and if you tend to hop trail hits
Frequency of trail hits
Tyre/rim volume
Bead/rim snugness
Rear suspension settings

If you aren’t on tarmac, you want to go quite low to slow the rebound which majorly improves speed and tracking/grip.

40PSI should be fine as it is rock hard. If you don’t mind me asking, are you heavy I supopse if you were nearing 100kg you might have problems? Or, more likely is your pump actually reading the pressure accurately?

Far too many variables involved, really is a case of trial and error, from experience I am finding NN’s very pressure sensitive and as asked above, 3-4psi really does make a difference between them gripping and pinging off everything.

Just to clarify im 90kgs and i am just trying to work out just how low i can go with the pressures.

buzz your right its probably going to be trial and error , keep dropping pressure towards 30 psi until i get my first pinch flat.

I ride mine at 40psi and managed to get 2 pinch punctures at coed y brenin, wouldn’t want to go much over 40 though! i think it’s a safe bet

What is everyone else running not tubless btw.

How about a rider weight tyre make tyre width and tyre pressure list?

Of course, this thread assumes everyones pressure gauge’s are all calibrated.

Ive had two and they were about 10psi different.

Short of everyone using the same gauge i guess thats what we have to do.

as asked above, 3-4psi really does make a difference between them gripping and pinging off everything.

I don’t think my track pump, or my eyes are capable of gauging such a small difference!

Squeeze the tyre – want it more like an orange than an apple

is what MTB course instructors seem to think is appropriate. Seems to work.

I found out a long time ago that 45-50psi worked for me and my riding style, any less and the pinch flats start.

Squeeze the tyre – want it more like an orange than an apple

I’ve eaten my apple for today. Will a tin of pineapple chunks suffice for comparison?

At last Dibbs thanks.

35 ish psi for me – any lessand the tyres squirm around in a horrid manner. Dunno how someone can cope with under 20 psi – that just feels awful to me

Hi Drook, that’s an interesting alternative. Please feel free to experiment 😯

Apple v. Orange was their polite way of suggesting we’d all overinflated our tyres, and that perhaps a few psi here or there isn’t actually the issue…..

I’m 85KG and have around 35psi. Although, I run tubeless now.

Never really gone up to 40psi with tubes though.

you need one of these:

http://singletrackworld.com/forum/topic/adaptrac-system

Some saying they run 18 and 15 psi is just crazy. My wheels would look in some state after about 5 mins.

i weigh just a shade over 90kg and run about 40 psi in my 29er tyres on my paradox.
if i run much less, i get pinch flats when drops or jumps go wrong.

works for me.

I always run a minimum of 50psi in mine the harder the better.
i certainly do not understand these low pressures at all 🙄

I guess running wide rims and high volume 2.4 tyres, oh, and yes, tubeless 😳 means I can get away with sub 20psi. Sorry to confuse, but even my tubes bike max 25psi.

peanut – do they not squirm / roll around under cornering?

They really don’t, they just feel as if they are molding more to the ground, more grippy and less like they are just ‘skimming’ over the surface as I find with higher pressures. More confidence inspiring in my experience.

fairhurst – Member

I always run a minimum of 50psi in mine the harder the better.
i certainly do not understand these low pressures at all

i despair..

I too am about 90kg and run 29er rims with NNs
I find 40psi way too much, about 25-30 seems to work for me.

the harder the better for my riding style pinhead

Is it common to ignore rec pressure ranges marked on tyres? My Bontragers tyres say 40-65 and I have them towards the bottom end. But I am always surprised to read mag articles and threads here talking about running much lower ps1.

Lower pressures do run more risk of blowing off the rim. I reckon that’s why manufacturers don’t recommend them.

I’m about 90kg with gear. XC hardtail has Small Block 8s Front:20-30psi Rear:25-35psi (depending on conditions\trail). I’ve found it’s a nice compromise with low profile tread and low pressure. It rolls fast, grips and conforms well and is forgiving on rougher sections.

AM bike has Nevagals with similar pressure. I’ve found some nobblys roll better on hard surfaces at lower pressure too, I think it’s because the nobbles recess back a bit giving a flatter contact area.

To be honest it’s all down to preference, do some experimenting and go with whats feels right for you.

TandemJeremy – Member

peanut – do they not squirm / roll around under cornering?
Posted 1 hour ago # Report-Post
peanut – Member

They really don’t, they just feel as if they are molding more to the ground, more grippy and less like they are just ‘skimming’ over the surface as I find with higher pressures. More confidence inspiring in my experience.
Posted 1 hour ago # Report-Post
This + 1
Run 23F/27R(tubeless)in the lakes with no problems

I started last year with tyres at 60psi, have been slowly reducing it to 40psi now.

Just starting to get wary about reducing it much more than 40psi. Might try 40R 35F tomorrow and see what happens.

Blimey, I’m a fat knacker (92kg) and with tubes I used to run 35psi. Now with tubeless I run 25-28 no probs at all.

When I first started biking I used 60psi… Now I’m at about 30-40 psi f+r depends on when I stop pumping, hadn’t thought about using different pressure f+r, I’m 74kgs riding a prince Albert. I found 60psi too hard but didn’t get pinch flats, I find if I go lower the tyre squirms way too much, oh and tyres are RR on back NN on front with tubes.

i was thinking of increasing mine up to 65psi