new tyre valve

[iancullen7]

my rear tyre valve split on the motorway not good thing to happen at speed Q is replacing it a diy job ' r car tyre valves the same fit if so woold i be able 2 get 1 from a tyre place rather than taken the back wheel off

[plodder]

Tubeless valves are fitted from the inside, so wheel & tyre both come off.

You have to cut off the old valve from the outside (flush with the rim or thereabouts) and pull the new one through with a tyre valve tool (you ever wondered what the bits on the 4-way tyre valve tool are for? Well the thing that threads onto the end of the valve is for pulling it through)

I use short valves (from M&P £2 each). As far as I know the hole size is the same so you could use car valves but remember that long stems bend with the centrifugal force of the wheel spinning and repeated bending causes failure.

Q for you... Did you have something like a "tyre fly" fitted to the valve. Don't do it they're bad news due to the weight added to the end of the valve.

[iancullen7]

you r spot on about the car tyre valve coz lookin at the valve it is of a long type not the same as the front is short and stubby type i was doin 120 ish this i where the failer happened your reply has been a great help cheers another thing ive learned today

[Evilchicken0]

You can replace the valve core if the outer is intact. They just screw out with a valve screw.

[fzrtim]

If you have a screw type bead breaker it is possible to replace the valve in situ.
The longer car type valves are the same diameter as the shorter ones prefered for bikes.
If you are attempting to fit the valve yourself (not a difficult job), make sure you lube it up before you push it in (yip yip)!

[plodder]

You also need a good air supply to re-seat the bead (preferably a 20ltr compressor, although you can get away with the one at the petrol station if you don't mind being stared at when it bangs and if it developes enough pressure as most only go to 36psi).

[iancullen7]

took the wheel off myself then cheated doin it myself as i dont have tyre irons took the wheel and valve to the local m garage done 4 a fiver not bad i thinks put the wheel back on aligned the wheel and gave the chain 3/4 in play usin a tape does feels better doin things yourself may not sound much to you guys but a big whooopi to me

[Evilchicken0]

That's roughly what I did when mine blew too.

[fzrtim]

I guess im lucky that as part of my job is supplying and demonstrating tyre machines (amongst other garage equipment), i get all my tyres fitted for free. In fact even better, i get paid!!
Just working on a way to get paid for trackdays now!!