I have just converted to tubeless for an trial using my stans flow rims and the stans tape and milk.

Its on my AM/trail bike, running single ply 2.35 Maxxis high rollers (supertacky front and semi slick rear)

just wondering what pressures anyone runs their tyres at? I’ve started at my normal pressures 35psi front and 40psi rear. whilst this makes for a very fast rolling set of wheels, they are much too hard compared to when i run tubes(thinking its because tubeless allows more air volume in the tyre for the same pressure) and don’t have anything like the grip i had with normal tubes.

so, has anyone run this combo or similar and any pressure starting pointers for me?

cheers

Well really you need to think about a few key drivers:

What do you weigh?
What sort of terrain are you riding?
How do you ride? (Smooth or plough through things?)

You are right that you now have a bit more volume but you also have bit less side Wall thickness, the tyre will comply more at the same pressures than it did with a tube…

You might want to consider lowering pressures a bit more though, for more compliance from the tires hopefully giving more grip and a better ride, high pressures with tubes are all about avoiding pinched tube really, you don’t have tubes now so high pressures won’t really improve flat resistance very much.

as for rolling resistance, well you are using a Semi slick on the rear, how much better do you want it? Tire tread and profile have a far greater impact on rolling resistance than pressure alone, off road it could be argured a softer tire rolls “better” across the uneven terrain.

Obviously too low a pressure and you run the risk of unseating or “rolling” the tire off the rim, you hear people claim they go down to -15psi for DH, I doubt that would work for many people long term…

I’d recommend you take them to 5psi below their old normal pressure (when you used tubes) and try that out, knock them down in 5psi increments until you find a happy balance between ride, grip and rolling resistance then make a note… It takes a few trial rides to get a good idea of what you’re going to be happy with, Front and rear pressures don’t have to match either, I tend to have about 5psi less in the front myself.

Basically experiment, it’s quite suprising how low you can go, but that’s not always ideal.

35rear 30front or there abouts…

on proper UST rims mind, no idea on stans etc…if there should be a difference at all?

16 stone, 140mm trail bike plough through most things and I am currently running a pair of Bonty XR4’s on Flows, 2.3″ at 24psi front and 28psi rear, seem to roll well and grip well

so basically what i was thinking then, run them at about 5psi less.

thanks for confirmation and i’ll let you know how it goes

25 front 30 rear is about as low as I can go before I get the dreaded squirm and hiss.

If it helps:

Bonty Mud X 2.0 – with tubes @ 50psi, tubeless @ 30psi
Maxxis Ignitor 2.1(?) – with tubes @ 35-40psi, tubless @ 25-30psi

Basically my tubed pressures were the minimum I could use and avoid pinch flats. Now I run a minimum that doesn’t let the tyre squirm around – I find that I can deal with 25psi tubeless but it’s right at the limit of starting to squirm. I’ve actually run them at 20psi and they were fine but I didn’t like the way they felt.

So, yes, less pressure than when running tubes.

Thought it might be worth telling my experience with the latest NN’s, and wondered if anyone else has had a similar issue?
Just bought a pair of these after previously having run the UST version for a couple of years with no problems. The weight saving looked good 😳

They went on the rims OK and inflated first time – but were flat next morning. I had added sealant and used lube on the bead etc.

As the rims were also new thought it might be a problem there – when I pumped them high I could hear a hiss close to the rim. Closer inspection revealed that there were tiny holes in the sidewall in a position that sealant was unlikely to reach. Finally got it to seal by laying the wheel horizontally for a while.

The supplier pointed out that they are sold as requiring sealant, but if this had been my first attempt at tubeless I suspect I would have given up by now and fitted tubes…

Not just Nobby Nics but lots of non-UST tyres leak from the sidewall initially.

That’s why you have to shake them on their sides to get the fluid all over the insides once pumped up. I had one NN that took a couple of weeks to stop developing new sidewall leaks.

Follow the Stans video for installing tubeless tires. They recommend holding the tire on its side and sloshing the sealant around the sidewalls to seal them. Normal procedure for installing tubeless ready tires.

Do the shaking then put them flat on their side (on top of a bucket works well, nice and horizontal) for 5mins each side, this will seal the sidewalls.