It would seem the tyres I’m running are fairly ‘slack’ and can easily be levered off with adequate thumbage. No need for levers. Maybe the kevlar bead is a little tired and has stretched over time.

Anyhoo, my point is the tyres move on the rim under braking and inevitably shear the valves off the inner tubes. Happened twice on the nightride last week meaning I had a long walk back to the pub.

I’m reluctant to bin the tyres as there’s loadsa life left in the treads.

Other than pumping them up to ‘rock hard’ or going tubeless, is there some home-brew method of helping secure a tyre to a rim?

Bumpity-bump.

If running tubes, lots of talc – helps the tyre & tube move independently. It won’t stop the tyre moving, but might save you ripping valves out of tubes.
If you go tubeless, provided you can get them inflated, then the sealant effectively glues the bead of the tyre to the rim.

Tried the talc thing… maybe didn’t use enough.

Have you tried different brands of tubes too? I’ve had some in the past that were terrible for the valve stems coming off (A brand beginning with B being the worst!).

What pressure are you trying to run them at ?

some in the past that were terrible

Yeah – two Schwalbes sheared off last week. Have since heard bad things about them.

What pressure are you trying to run them at ?

Quite low. But large-ish volume (29er 2.35 tyres) on a rigid bike so… about 35psi?

Can you stick the tyre beads onto the rim somehow? Perhaps some hairspray or weak flour and water solution?

Perhaps some hairspray

Experimented at lunchtime with some black spray-paint. I figured I’d try what I use to stick grips on 🙂

We’ll see if it holds on tonight’s ride…

Paint may be ok, I was thinking that something like hairspray may not be too strong that you have problems getting the tyres on and off, or the beads being damaged when you do.

The only problem is that it is hard to find someone who uses hairspray to borrow it off!

drag yourself into the 21st century and run them tubeless?

(i’ve just jinxed myself haven’t i, i’ll be the one walking to the pub later!)

how about some electrical tape around the rim bead on both sides?