As above really, everytime I land sideways, some air comes out… Can I do anything to stop this? Using Mavic 819 Rims, and various tyres…

Use tubes?

Which tyres?

Have 819’s myself and weigh 15st; never burped a proper UST tyre.

which tyres?

pump em up

I have burped UST high rollers on 819s when the pressure is too low doing the same thing; doesnt happen on my Stans rims.

pump tyres up harder.

I have been using tubeless for 5-6 years, only ever experienced burping from Stans rims!!! Picking latex out of the hair on my arms after ripping around a corner! This happened a lot, having had two pair of olympic rims and one pair arch.

UST rims have never burped, when used with UST tyres. STD tyres are rubbish tubeless, a very loose hold on the rim and burp all the time.

If you ride hard/aggressively you need to put more than 30psi in your tyres at all times, the lighter the ytre the more air.

IE, a dh high roller 2.5 on a mavic EX823 rim can happilly run at 30psi and be leant on in corners.

A Maxxis crossmark LUST burps and folds over in corners if run at 30psi, run at a minimum of 35psi it feels great.

this is why i’ve not tried tubeless again. i run around 25 or 30 psi in the front and about 30 in the back. when i ran tubeless before i had to run higher pressures to avoid burping.

surely with tubes and 25-30psi you just pinch flat all the time, don’t you? Do you ride a lot of rocky stuff? Are you using very heavy tyres and tubes?

I run tubless at 25-30 and don’t suffer from burpping. Do you mean that if you land the wheel sideways that the tyre burps? if so i have only ever done that once and would expect any tyre to do that as you are trying to pull it off.

As above, what tyres, tubes and pressure?

I carefully install my tubeless tyres, ensuring the bead and rim is 100% clean. I run a thick mixture of pure latex on the bead before first inflating. This reduces burping alot. Leaving the wheel for 12hrs + at very high psi for it to glue onto the rim can help alot.

The only burping I suffer from these days is very very hard landings on my dh bike. Last did it accidentally doing 6ft+ to flat on the front wheel, even then it retained enough pressure to ride it out. I suspect with a tube it would have pinched.

I had some failures running tubeless on my 4X bike running very high pressure, they’d blow off landing sideways or hitting berms hard. I’ve since stopped using it for that use. High pressure, kevlar beads and tubeless doesn’t mix well.

It will depend a lot on tyre and rim combinations. My experience of Mavic UST is a bit limited but I found Maxxis UST tyres burped very occasionally on an 823 at around 25psi or less. Over that it was mostly fine.

Working with NoTubes rims every day I’ve tried most combinations, and the only way I’ve found to guarantee no burps at very low pressures is with a rimstrip. Mostly I ride Flows at around 18-22 psi. Single ply tyres and yellow tape gives regular burps, UST tyres and yellow tape I have managed to burp about once, dual ply and yellow tape occasionally burps under sideways landings, and dual ply and rimstrips is totally burp-proof, for me anyway.

For XC wheels I find Olympic and ZTR 355 rims and rimstrips are near enough burp-proof. I couldn’t say for sure that it never burps, but I don’t remember it ever happening.

Really the only way to guarantee no burping at low pressures is to use rubber rimstrips, the reason being that they can move with the tyre if need be and create a better seal in the first place.

Take a look at Stan’s movie here, I wouldn’t say it’s quite as simple as he makes out and it’s probably not exactly the same as real-life testing but it’s interesting all the same:
tyre burp comparison

burp-proof. LOL. word of the week?

well, the rims as i said are mavic 819’s, and the tyres are UST kenda nevegals. They are pumped up to around 35 – 40 psi. When i say landing sideways, i dont mean literally, but when i hip a jump or such like… It is far worse with the nevegals than any other tyre, so maybe they’ll have to be ditched…

Lyons – Can you email me please.