So riding in the snow, across pretty innocuous terrain when the back tyre goes down.

Find I have a small tear in the sidewall of my continental speed kings. I also tore my last tyres sidewall quite fast too. Both only tiny tears but annoying non the less. Both on pretty mild terrain.

Is there anything I can do to prevent this or reduce the likelyhood of it happening? Does tubeless make it more suseptable? Or is it because of the tyres I am choosing?

it's 'cos you're using a lightweight tyre – they cut right down on the sidewalls to save weight. I have the same problem with Nobby Nics.

tubeless is probably nto an issue unless you are runnign very low pressure when you can get pinch flats int he tyre

Maybe its your tyres, pressure, terrain.

Whats the terrain like, do you have lots of flint where you live?

No flint. Last night it was snow, snow and maybe a bit of slush and ice. I suspect I slid the back wheel sideways and it hit a twig or something? but this is only a guess?

Tyre pressure was 30psi when setting off.

Was it the sidewall or at the bead? I get through a few at the bead, local sandy gritty trails seems to get twixt rim and tyre bead and wear it through.

UST tyres have thicker sidewalls due to extra layer of rubber, but it doesnt mean they are harder to rip.

The expensive Protection or Snakeskin whatevers might be a good purchase, better £ than binning a nearly new tyre.

thin ass tyres, combined with pointy local ground!
invest in some protection ones, and consider the weight training, then put speed kings back on when it matters?

i patch smaller holes in the tyre wall, incidently, using one of those sheets of tube manding rubber, and a tube of glue (cut an appropriate sized patch from the sheet, not use all of it)

Speed Kings are crazy thin on the sidewall. Haven't cut mine, but I am cautious all the time, which is not ideal. Going back to my favourite tyres when these are worn out.

Think I have learnt speed kings fast but fragile and lethal. But great in mud and snow.

Not too fussed about the tyres as they were bogof on-one speed kings and a good excuse to get some new ones on. But just didn't want it to keep happening as I am now accruing a lot of rubber in the shed.

Will try and patch and run tubes for a bit I think whilst deciding on a new set of tyres.

An tips to stop it happening n future or is it just simply don't buy such rubbish tryes?

I successfully repaired a small side wall rip (~5mm)in my front racing ralph by glueing inside a piece of sidewall cut out from an old tyre. Worked a treat and still running now after some 8 months 8)