Fat Tires & Tire Pressure

Slevin

New Member
Just got a new Juiced bike with fat tires - I'm starting to inflate the tires and see Juiced recommends 25 PSI in these fatties.


I'm at 12 PSI in the front and it's already super hard to squeeze, feels like it's ready to blow. Am I doing something wrong here? I'm using an electric tire pressure gauge to check PSI.

I know this is a ridiculous post, sorry, and thanks for any input...
 

Tars Tarkas

Active Member
Try another tire gauge for starters. They can be amazingly inaccurate. Beyond that, 25 psi sounds like a decent starting point. Try it for a while, try 5 psi higher or lower and see what you like. There's no right or wrong answer.

TT
 
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Smong

Member
I'm new to fat bikes although in the past I was a sponsored regional MTB racer so take my comments accordingly...also I'm mid 60's, 150 lbs with some health challenges but still ride some crazy terrain and nasty trails.

When my M2S Ultramax HT came in the 4.5" tubed tires were inflated to 20 psi so naturally I tried it around the neighborhood like that. Didn't seem too bad so took it to a groomed snow MTB trailhead where I was advised to lower it to 10 psi. Even that left me with a rounded tire profile on the snow so I dropped it to 5 psi. After a 150+ miles on the snow, I've settled with 5psi in the rear and 4 psi in front for superb traction and handling. If I were to ride those tires on hard ground they would go up about 5 psi more. They would not my choice for summer trails and I also have a pair of 27.5" wheels with 3" tires that are way better suited for that and will probably be run around 12-15 psi. Eventually I will get some smooth tires around 2.5" for summer, which I think will be even better for pavement at 50 psi.

There's no generic answer for how much pressure to run, it depends on your weight, trail conditions, size and construction of your tires as well as riding style, etc.. For a fatbike in snow or soft ground the goal is to have your tire squished completely flat on the bottom. When you run those same tires on the pavement like that they will 'wallow' in the turns, self steer, and they'll feel like crap. Bump it up in psi to round out the contact patch and they will handle somewhat better but be very loud. Fat's are fun but not very confidence inspiring at speeds much over 20 mph and scary at 30 mph...for me.