Good thinking.

Why not just deburr the edge of the valve hole?

Because that would require a craft knife silly

Dougal wrote:Why not just deburr the edge of the valve hole?

No visible "burrs", infact it doesn't even seem sharp. Worn smooth and barely hanging in there would be how I'd describe it.

S

Are you using those valve nuts on the outside?

both sides
S

sarahk wrote:both sides
S

Throw them away, they're an evil ploy by tubemakers to sell more tubes. All they do is rip the valve stem out.

Dougal wrote:Throw them away, they're an evil ploy by tubemakers to sell more tubes. All they do is rip the valve stem out.

Which was the original problem...

I'll set one bike up one way, another up the other and see what happens

S

Dougal wrote:

sarahk wrote:both sides
S

Throw them away, they're an evil ploy by tubemakers to sell more tubes. All they do is rip the valve stem out.

Bollocks,I always run them(except with the ghetto tubeless) and have never ripped a stem out,lack of talc or crap tyres will do it,if the tyres rotate on the rim cos the bead isnt gripping properly and the tube has stuck to the tyre it'll rip the stem off.

Percy Pig wrote:

Dougal wrote:

sarahk wrote:both sides
S

Throw them away, they're an evil ploy by tubemakers to sell more tubes. All they do is rip the valve stem out.

Bollocks,I always run them(except with the ghetto tubeless) and have never ripped a stem out,lack of talc or crap tyres will do it,if the tyres rotate on the rim cos the bead isnt gripping properly and the tube has stuck to the tyre it'll rip the stem off.

I stopped running them about 10 years ago when I ripped a couple of valve stems out. I haven't had it happen since.

I don't believe that talcing the tubes makes any difference. In a 2" tube there are over 2000 square centimetres of tyre to tube contact, mulitply that by the tyre pressure (30psi = 200kpa = 2 kg/cm, roughly) and you've got about four ton of force holding the tyre against the tube.

If you think that a little talcum powder can drop that enough for the valve to hold without ripping, then that's fine. But I think it's a little unrealistic.

I run talc, but no crappy little nuts.
Then again - I run Schrader... and haven't punctured in well over two years.

Stun wrote:I run talc, but no crappy little nuts.
Then again - I run Schrader... and haven't punctured in well over two years.

I had an exhaust induced puncture early last year.

Stun wrote:I run talc, but no crappy little nuts.
Then again - I run Schrader... and haven't punctured in well over two years.

Hoped you just touched some wood* because you just brought down a mighty jinx on your ass....

*

Stun wrote:I run talc, but no crappy little nuts.
Then again - I run Schrader... and haven't punctured in well over two years.

I run talc, but no crappy little nuts.
I run presta... and haven't punctured in well over two years. I ride a XC / trail bike with lightweight tubes and single ply tyres.

oh and before JB says it, Dodzy said the nuts were a waste of time as well.

and Dougal, whats the lateral force on a tyre? by lateral I mean sideways when you are hard out cornering.

They dont count.

And I dont know why but talc seems to work,I used to get pinch flats all the time untill I started using loads of talc.

Mind you even before the talc days I never ripped a stem out.