No, not out chubby chasing tonight – even worse, it’s a tyre pressure question.
Got my On One Fatty Trail delivered in the week, first ride is this Sunday (Cannock). Thing is, having never owned one before – what’s a good starting base for the tyres?
Tubed, Jumbo Jims, Blutos and a 14st rider. Seen some say they ride as low as 8 PSI? 😮 , I’m guessing that’s for snow.

Thankyou.

8 is about right.

8 front, 10 rear. Take a pump and adjust to suit

Oh & avoid anything muddy using JJs

3 psi front and 4 psi rear in snow last night.

7 psi for rocky and rooty stuff in summer.

14.5 stone rider.

In a real mix of units: start with 1psi for every 10Kg of rider (and kit) then adjust to suit. It’s usually downwards 😆 Generally you keep dropping the pressure in as small amounts as you can until you don’t feel like you are pinging off everything. Worth getting a pressure gauge that is suitable for low pressures. Also the pressure that works for one model of tyre might not be right for another, you’ve got to start all over again.

I’m 87Kg and run with 9psi front, 9.5 – 10psi rear which is good enough for general riding, if I go too low, say 7psi on the front then the handling gets weird especially on road.

Very terrain dependant. I run as high as 12psi on smoother trails and put up with the occasional pinging around, nearer 8psi when it’s rougher and rockier. 6psi in snow. Inevitably, some rides require a bit of compromise. I bought a wee digital tyre gauge from Halfords. Dunno how accurate it is but it’s consistent.

I run 8psi in 4.6 Spesh GC’s (tubed) as an all-round compromise for all conditions but snow. Higher and there’s a big to much pogo-ing.

Some guys on the beach Tuesday night dropped theirs down to 3-4 ish.

I’m too lazy to pump them back up when I get back to firmer ground, though…

as scotroutes said..
11-12 psi on smooth,dry trails
8 psi for general trail use
for snow a bit less..

whitestone – Member
In a real mix of units: start with 1psi for every 10Kg of rider (and kit) then adjust to suit. It’s usually downwards

This is how I started and was able to dial my preference in! It was indeed downward also 8)

There’s some advice on tyre pressures for riding in snow here. The comment about leaving a flat track rather than a curved one is probably something to aim for.

id have the front a little harder to make sure the blutos are effective, if they are too soft it kind of defeats the object of suspension on the front, but again depends on the conditions 🙂

8 psi in snow would be pretty useless IME, maybe for groomed, frozen hardpack but it’ll be choppy. Back up to arctic next month – if it’s anything like last year with deep, fresh snow it’ll be 1-2psi in the tyres for maximum float and grip, 5″ front and 4.8″ rear. I normally run 5F/6R for normal riding – no point in going higher as I don’t want to ride a space-hopper.

I am on Maxxis FBF and FBR running 6.5 and 8 at present, all good.

Just have a play and trust the low pressures to start with although it does screw with your mind when you think of the pressures in skinny tires 😉

Best wishes,

James

Size makes a difference, more volume allows lower pressures- so frinstance with my 4.0 JJs I had to run 9 psi or above or I’d pinchflat, with my 4.8s I run 6 or 7. (I weigh 10 stone but otoh I probably ride it a bit harder than most)

Taste plays a big part too though, I want mine as low as I can reliably get away with for maximum “fatness”, that’s the feel I ride my fatbike for. But that has downsides too. And I don’t really want to muck about with pressures that much so my minions are constantly at 6/7. But that’s riding specific too, my snow rides usually still incorporate some bombing so I can’t drop to snow pressures without having trouble on the harder bits… ymmv.

Get a decent pump and a couple of spare tubes, go forth and ride, and puncture. Only way to figure out what works for you, imo.

I rode Cannock a couple of weeks ago on the same bike. It’s perfect for those trails.
If you’re riding it like a trail bike, then you’re at risk of pinch flats if you go too low running tubes. I’d keep the rear above 10psi and a bit less up front.
I’m 77kg and have found 8 rear and 7 front to be the sweet spot running tubeless – you’ll be wanting to go tubeless asap.
Those comments above about really low psi tend to be for more XC riding on sand and snow.

I usually ride with around 7psi front and rear…. Lower if/when it snows in the cotswolds.

Echo comments from Northwind, Scotroutes; I run about 6 & 7psi tubed with both Minions and Floaters; 76kg + kit.

I’m also a bit of a heretic; I think tubeless is over-rated, especially on fattys. Maybe riding fully rigid helps with this; makes good line choices and smooth riding vital to staying friends with your wrists! However, I rarely ride modern built trails, so that might explain the difference in perspective to sgn23

Thing about tubeless and flats is, if you would have pinchflatted regularily on tubes, you’re going to batter your rims on tubeless with the same pressure. I’m still a fan, for sharp punctures, weight loss and rolling resistance (especially on the fatbike!) but not so much for rim dinging. Though again, maybe a ymmv, sand and snow riding might be different with less sharp edges to bash on?

Thanks all.
Yes, it will be rode likes trail bike and mostly at Cannock, yes the low pressures really do **** with your head, luckily, I’m totally analysis about it and bought a Topeka digital gauge years ago.
I’ll use that formula and go from there, probably starting at 12 rear and 10 front and suck it and see.
I am definitely going tubeless in the Spring, the thought of carrying tubes and punctures is depressing already, been riding tubeless on my mtb’s for 3 years now and am a firm convert, though tis a very good point about rim dinging at ultra low pressures.
Thanks again, interesting stuff.

It’s worth carrying a tube just in case you split a side wall or something similar that sealant can’t cope with. Just get the lightest you can find, a 3″ innertube will work in a fat tyre so I’m informed.

My wife got two massive thorns in her tyres at New Year, tubeless so no problem. Does depend on where you ride though, unlikely to get thorns at trail centres for example.

Knowing the available options and making an informed decision based on where you ride and your riding style is better than either blindly following fashion or refusing to acknowledge anything but what you already have.

In true ‘play your cards right’ style: Lower! LOWER!!! 🙂

Great advice about going out a trying, but I suspect you’ll end up wiht less than that. If I want to zing about pinging off stuff, I’ll ride t’other bike, If I want ridiculous traction and grip – it’ll be the ICT and 6psi front and 8psi back (bud and lou, clownshoes, 18.5 stone)

whitestone – Member

Knowing the available options and making an informed decision based on where you ride and your riding style is better than either blindly following fashion or refusing to acknowledge anything but what you already have.

Aye. And even more so for fatbikes where people use the bikes so differently, your idea of what fatbiking even is could be totally different to the next.

I run 8 psi front and 9 psi rear with 4″ JJ’s on 80mm rims set up tubeless. Also running a bluto, I’m 80kg btw

Northwind has a point, my idea of fat biking is the same as my idea of riding my ardcore HT but without the bigger drops (seems like a bad idea with rigid forks). I can’t believe how much of a hooligan the Dune feels.

I like the floaters a little harder and 10 is fine but needs 12 at Glentress otherwise i get tyre roll in corners. 13st 13 (in denial about being 14st…)

For the commute home once a week, 20 – 25 gets a nice roll on.

I like the floaters a little harder and 10 is fine but needs 12 at Glentress otherwise i get tyre roll in corners. 13st 13 (in denial about being 14st…)

For the commute home once a week, 20 – 25 gets a nice roll on.

I’m around 110kg and run the 4.0 JJs with tubes in at 8 psi at the Chase with minimal issues (the only issues are off piste in the mud and lack of grip). For winter I run Floaters at 8psi front 9psi rear and they grip a bit better in the Chase Paste. Have fun!

On Floaters by the way, 7psi both ends, back end seeps a little but doesn’t lose air, might go up to 8psi.. 12st

Still (slowly!!) building a Puffin, but will be running the On-One Emmental wheels with 4″ JJ’s. Just waiting on a pair of 2.5″ BMX tubes to set the wheels up ghetto tubeless.

Currently running a 29+ Knard & b+ Trailblazer combo at 12psi / 15psi. One thing I’ve found, even on the current combo, is that even 2psi has a big effect. The Topeak digital gauge is pretty accurate, I checked it at work on some calibrated kit.

Thats good news on the Topeak gauge, nice to know its accurate.