Hi all.

I recently got a new bike which came with UST tires/rims which is new to me as I’ve been using tubes for many a year.

So I have a couple of questions –

Firstly, do I really need to much about with putting liquid sealant into the tires? I get the idea but not really keen on it if I can avoid it.

Secondly – tire pressures. I thought that one of the benefits of tubeless was the ability to run lower tire pressures. I usually run somewhere around 30psi on regular tubed tires but the new tubeless tires say they should be inflated to between 35 and 60 psi. That sounds pretty high to me.

Sealant isn’t necessary if you have both UST rims and tyres. BUT… It’s very wise to use some! Without sealant you’re still prone to little thorn punctures and the like, and I can tell you that every time I come to swap my tyres over on my bike, I’ve always got something embedded in the tyre that would have caused me to stop and put a tube in without sealant in there…

In fact, here’s a photo of what I found in my tyre the other weekend, that sealant sealed no bother…

Just to give an alternative view – I run UST rims and tyres without sealant, but then I’m blessed with thorn free trails. As for pressures, I think tyre manufacturers just put those on to cover themselves, and I’ve run mine as low as 20psi without any problems, especially as proper UST don’t burp like ghetto tubeless.

especially as proper UST don’t burp like ghetto tubeless.

I’d say the contrary is true actually. By far the most reliable method I’ve used is the ghetto method with a BMX inner tube used as a rim strip. It just rolls with the tyre keeping contact with the bead if you roll the tyre heavily, whereas proper UST setups can be susceptible to burping under heavy side loads if the tyres aren’t ridiculously tight.

As for pressures, drop them 10% over what you run in tubes and try that. Don’t go too low otherwise you’ll damage your rims easily and burp tyres all over the place.

As usual, for every opinion, there is an equal and opposite opinion. Or something.

I’ll drop the pressures a bit and use without sealant for now and see how it goes.

I’m off to Afan this weekend so some rocks but probably not much in the way of thorns.

Heh – depends on tyres and rims as well as rider weight as to pressures.

I run narrowish xm819’s rims with wideish ~2.35 tyres, so I find I run about 30-35psi to prevent the tyre burping (I’m 220lb), change the combo of rim width/tyre size/rider weight to wider/thinner/lighter and you can drop your pressures lower.

I run predominantly with no sealant – I forgot to top up after 6 months and never got around to it on my bikes except on one that had a slow rear puncture. Depending on your valve you might be able to remove a Schrader core and pour sealant in that way.

Main benefit to UST/tubeless is the better grip and rolling resistance plus immunity to pinch flats, puncture resistance is a happy side effect as far as I’m concerned. UST tyres are tougher than normal tyres, so they shrug off a lot of thorns and stuff anyways.

Firstly, do I really need to much about with putting liquid sealant into the tires? I get the idea but not really keen on it if I can avoid it.

No you don’t have to UST rims/tyres cna be run “dry” if you like, but if you manage to pick up a small hole in the tyre then it won’t self seal, one of the major benefits of UST (if used with sealant).

Secondly – tire pressures. I thought that one of the benefits of tubeless was the ability to run lower tire pressures. I usually run somewhere around 30psi on regular tubed tires but the new tubeless tires say they should be inflated to between 35 and 60 psi. That sounds pretty high to me.

I’d say treat that as manufacturers recommendation rather than Gospel, TBH it’s there to be ignored… Start at whatever pressure you normally run (30psi wasn’t it?) and then see how it feels then maybe try it at 25psi see if that’s better or worse, you’ve just got to experiment really.

The balance you are trying to strike is Grip, Traction & Comfort Vs Rolling Resistance, pinch flats shouldn’t really be part of the equation any longer… Oh and whatever specific pressures someones mate of a mate down the pub or a fella of the interweb says is “Perfect” ignore them, go with what you find suits you best.