Tyre not holding new inner tube

[markemark]

My wife’s bike has had first puncture. I’ve replaced dozens on my bike without issue.
Rear wheel new inner tube is pushing the tyre off the rim. Tyre says 700x40. I’ve bought continental 700 32 to 47.
Below is what happens shortly after inflating. I’m on my second inner tube and have rotated the tyre around. It always pops out where the valve is. It’s like the rim is not holding the tyre so as I inflate the tyre is pushed out of the rim on both sides.

 

[notmyrealnamebutclose]

Let all the air out first then squeeze tyre walls together going completely around the rim and then try again

 

[fossyant]

Had this with a neighbour's bike, both wheels - sometimes the tyres aren't a good fit, especially cheap ones. You've got to double check you've got the tyre pushed into the rim, then check as you re-inflate it.

 

[pawl]

If the tyre is not seating correctly at the valve push the valve up into tyre and the tyre down into the rim.Should seat the tyre allows more space for the bead to seat

 

[Ajax Bay]

Fit the tyre. Push the valve in and push the beads of the tyre either side of the valve in with diligence. Pump 10 times. Go round each bead and check they are seated. Bounce, turn and repeat. Inflate to riding pressure.
I shall take it the rim says 19-622 and the tyre has 40-622 on it.

 

[T4tomo]

that lock nut isnt helping, take it off, as that is stopping the tube moving sufficiently into the tyre to allow the tyre beads to seat on the rim wall.

its a completely superfluous nut, as when the tube is inflated the valve is held still anyway.

do what @Ajax Bay bay says above (after you've thrown that nut in the bin)

 

[markemark]

Thank you all that’s got it. I’ve normally just fed the inner tube into the tyre, pumped and it all works out.

I removed the nut and pushed the valve so the inner tube was well into the tyre, then fitted the tyre nicely into the rim. Pumped it up and all good. Are these crappy tyres I should replace or just make note of the process??

 

[markemark]

View attachment 669735

that lock nut isnt helping, take it off, as that is stopping the tube moving sufficiently into the tyre to allow the tyre beads to seat on the rim wall.

its a completely superfluous nut, as when the tube is inflated the valve is held still anyway.

do what @Ajax Bay bay says above (after you've thrown that nut in the bin)

Nut removed. Shall I sell it here in the for sale section?

 

[Sallar55]

The valve nut and cover go in the bin. 😁

 

[Ajax Bay]

View attachment 669735

that lock nut isnt helping,

You 'spotter'!

 

[T4tomo]

Are these crappy tyres I should replace

no reason to ditch the tyre, especially now its seated properly. if it keeps puncturing frequently, then you might want to

 

[Ajax Bay]

The valve nut and cover go in the bin. 😁

Agree for a Presta valve, unless the cover is an essential element of a bike's colour scheme, but for Schrader I'd keep the cover on: the orifice is big enough for grit to get in and interfere with the valve's over-pressure operation.
Do you ditch the covers on any car tyres you use?

 

[T4tomo]

Agree for a Presta valve, unless the cover is an essential element of a bike's colour scheme, but for Schrader I'd keep the cover on: the orifice is big enough for grit to get in and interfere with the valve's over-pressure operation.
Do you ditch the covers on any car tyres you use?

the cover also provides a modicum of protection for the presta valve, as well as the obvious bling by having fancy coloured ones...