Help please, first time fitting tubeless.

[Racingt]

Dear all
Santa brought me a lovely pair of tubeless ready wheels and a pair of GP5000TL's.
So far, I've fitted the valves and tyres, and inflated both tyres to a suitable pressure.It was a wrestle fitting them over the rims, but both went on, using Cycling Plus tyre levers.
No sealant added yet.
One tyre holds pressure overnight.
The other flats.
I've checked the valve core is tight in the flatting tyre, also that the valve stem is inserted firmly, with the nut fixing it tightened down.
Is it possible that i damaged the airtight rim of the tyre during the fitment?
Should I obtain & insert a new valve?
Should I dunk the entire wheel in a stream in an attempt to find the air leak?
Or should I simply say 'nuts to tubeless', whack a tube in & ride.

Advice gratefully appreciated, regards.

[Paulatic]

Why not add some sealant?
Tip; after adding sealant only put a small bit of air in ( below the min tyre pressure) hold the wheel on its side and swirl it about. Then blow it to required pressure.

[RickH]

How have you "seated" the tyre? Have you used a tubeless pump/airtank to push it into place? Sometimes a tyre will inflate easily without an air blast but sometimes it needs that sudden burst of pressure to get the bead seated fully in place (usually with a pop).

[CXRAndy]

I like to hear two pops as the tyre seats on the rim. I use a compressor to force lots of air volume to quickly seat the tyre

Once the tyre is on, I then remove about 6" with tyre levers, turn one lever sideways to create an opening. Pour in 75 millilitres of Orange seal 'Endurance'

I then roll the fluid to the other side and refit the bead Ive just lifted. Inflate to max recommended pressure.

Roll the wheel in all directions to coat the entire insides.

I use Stans rim tape, two layers, making a robust protection against spoke hole blow through. Get the correct width for your wheels, clean carefully with alcohol before fitting tape.

[RickH]

Once the tyre is on, I then remove about 6" with tyre levers, turn one lever sideways to create an opening. Pour in 75 millilitres of Orange seal 'Endurance'

The Orange sealant I got came with a tube to attach to the top of the bottle. The tube fits over the valve with the core removed. That seems a much better way of adding the sealant than partially unseating the tyres you've just fitted.

[mattsccm]

It sounds as if you are getting the duff one inflated but it loses pressure. If so try using a bit of soapy water around both beads and inflating hard. Max pressure maybe. It should pop on. If it won't even do that you'll have to find the gap. If you can get pressure then add a bit of sealant. Best way is via a valve with removable valve. I use a syringe. Pump it up hard and swill the sealant round a bit. Usually works for me. Or sit in a wheel jig and spin it, prayer wheel style, and keep the wheel moving.
Just check there isn't anything daft like the tape being misplaced.
Spread soapy water all over the tyre and the bubbles may show you the leak.
You obviously have a decent set up or one wouldn't work.

[Racingt]

Only one tyre 'popped' on, and only one pop at that. I cannot recall which tyre it was.
The problem tyre is quite happy to be inflated, and deflated without any 'pop' whatsoever. Deflated, it is easy to move the beads inside the rim - so it isn't seated in place.
Currently it loses 75psi in about 4 hours.
Next plan, therefore is to try and pump more vigorously, using the function on the track pump which adds air on the upstroke as well as the downstroke. Go to 100psi as fast as I can?
Should I use one of my CO2 cartridges instead?
Maybe apply soapy water to try and assist seating.
I don't want to add sealant until I'm sure its seated properly, since I think I need to sort the problems one at a time.

This is really unnerving, I've been able to mount tyres and inflate them for over 50 years now, and with new technology, I can't. I have ridden tubeless wheels for 18 months now, completely trouble free, this is my first attempt at mounting tyres..

[dim]

ok, do this:

add 50ml of sealant per tyre (preferably Orange sealant, the regular version not the endurance version ) .... if you don't have that, use whatever you have (I like Orange regular and have been using it for a few years

replace the valve stem and rotate the tyre to between the 9 O'clock to 12 O'clock position so that the sealant is at the bottom of the tyre

pump with a track pump .... spin the tyre a few times

it should seat and be ready to ride .... go for a short ride to spread the sealant

the sealant will seal any side leaks (normally, if there is an air leak, it will be near the valve)

one thing about the Continental GP5000 TL tyres is that on some rims you will not hear it pop when it seats into the rim (I find this on my new wheelset which is HED Belgium Plus with one layer of HED tape especially made for this rim .... the tape states only 1 layer of tape must be used) , but pump it up to the max what your wheel allows (not the tyre), then let out some air

If you are struggling to mount the Conti GP5000 TL you may have too many layers of tape

if you need to use tyre levers, get the IRC tubeless tyre levers from Cycle Clinic .... these are quality, won't damage your tyres or rims and can be used with normal clinchers aswell

when you are on the road, you need to carry a Co2 kit .... you need the 25g cannisters and a unit such as the Leznye Control drive where you can regulate how much Co2 to use .... if all air is lost, your small pocket rocket hand pump will not work at all

[Racingt]

Oh, hi Dim!
We spoke on weightweenies about the HED Belgiums. I ordered a pair today, on DA. They will run tubes initially.
This post is for my 'other' bike, replacing Mason X Hunt with DT Swiss ERC1400's.
Cheers

[Brucey]

if the tyre hasn't gone pop then it is either too tight or too loose on the rim.

cheers

[ross.anderson.58]

Similar things happened with mine. Valves and strips fitted. Put the tyre on. One held pressure. One flatted overnight. Added sealant to both, both hold air fine.

I'm a trendy consumer. Just look at my LG-H930 using hovercraft full of eels.

[Marcus Aurelius]

Do yourself a favour. Take the tubeless tyres off, and throw them in the bin, where they belong. It’s for the best.

[dim]

if the tyre hasn't gone pop then it is either too tight or too loose on the rim.

cheers

does not mean that it's not seated ....

tyre companies are stressed when people buy tubeless tyres and cannot fit them to their rims, so they send them back for refunds to places such as Wiggle

so, they make 'tubeless easy' tyres now ....easy to fit

rumour has it that this year, there will be new laws and specs laid down as regards tubeless rims specs and tyres and from what I have heard, Continental will be heavily involved .... so hopefully, we will get a few more decent tubeless tyres such as Continental Grand prix 4 seasons in tubeless (that will be a great touring tyre in 32mm wide)

[NickJP]

Once the tyre is on, I then remove about 6" with tyre levers, turn one lever sideways to create an opening. Pour in 75 millilitres of Orange seal 'Endurance'

The Orange sealant I got came with a tube to attach to the top of the bottle. The tube fits over the valve with the core removed. That seems a much better way of adding the sealant than partially unseating the tyres you've just fitted.

Ditto here. Rather than unseating the bead to add the sealant, I remove the valve core and inject the sealant through the valve. With a properly designed tubeless rim, the beads stay in place with the tyre deflated. Sealant top-up every few months can be done the same way.

[rfryer]

The problem tyre is quite happy to be inflated, and deflated without any 'pop' whatsoever. Deflated, it is easy to move the beads inside the rim - so it isn't seated in place.

Maybe apply soapy water to try and assist seating.
I don't want to add sealant until I'm sure its seated properly, since I think I need to sort the problems one at a time.

I think you're on the right lines. It sounds as if the tyre hasn't seated. I'd try mounting it first with an inner tube to stretch the bead, then refit it tubeless after smearing the bead with fairy liquid to help it slide into place.