Tubeless on default rims

[Blakey]

When I bought my Amflow PL I paid the extra few quid to have it set up tubeless. Then a few months later I had a nasty puncture which has split the tyre. I believe I have fixed the tyre now, but when I try to put the tyre on and inflate it, the air comes out of the rim. It is escaping from a small, drilled, hole in the side of the rim, not from the channel where the rim tape runs. There are two of these holes, opposite the drive chain on the same side as the brake disk. The holes are directly opposite each other on the rim. Both my front and rear rims are identical and have the same holes.

I have tubeless set up on the front tyre with everything identical and no air comes out of those holes but on the back one it does.

One of my mates thinks the holes might be to allow air to escape when the tyre is seated and that the issue is that the tyre isn't seated right (though it "pops" onto the rim).

Any suggestions on what might be wrong?

Thanks
Blakey

 

[Astro66]

The tape is leaking. It will need to be redone.

Also check the valve stem.

Air is getting from the inner wheel layer to between the layers and coming out the hole. I'm assuming it's the carbon rims, and the nipples make a reasonable seal, so air comes out these holes when there is a leak.

 

[salko]

There is no reason to have any holes on a rim bead. Post a photo of this hole so we can access what this could be.

 

[Pentti]

There is no reason to have any holes on a rim bead. Post a photo of this hole so we can access what this could be.

Small holes on the sidewall or bed of carbon rims (typically 2.5mm) are standard drainage holes used to release water that enters through valve or spoke holes during wet rides. They also act as pressure relief vents to prevent dangerous air pressure buildup within the rim cavity when using tubeless tyres.

 

[RustyIron]

Any suggestions on what might be wrong?

The hole is on many rims. If you have a lot of air coming out, it's because your rim tape is leaking. Remove the existing tape and put in new.

 

[salko]

Small holes on the sidewall or bed of carbon rims (typically 2.5mm) are standard drainage holes used to release water that enters through valve or spoke holes during wet rides. They also act as pressure relief vents to prevent dangerous air pressure buildup within the rim cavity when using tubeless tyres.

Hole on a rim sidewall yes, but not on a rim bead... If he has a leak from a hole on a rim sidewall, then his TL tape is leaking and needs to be replaced...

 

[Blakey]

Thanks all. Looks like I need to redo the rim tape.

I'm not really understanding the flow here, mind you (but I am a bike noob so I am sure it makes sense to experienced riders - I'm not questioning if you guys are right).

So, the rim tape goes on where the spokes fit the wheel rim. Makes sense. Stops air getting out via spoke holes and valve hole. Check. The tyre snaps into the rim outside the canyon where the rim tape fits. Stops air escaping out of the edge of the rim. Makes sense.

But if there is an intentional hole in the side of the rim how is that normally covered up? Via the tape or the tyre?

 

[salko]

This image may help you understand: red one is TL tape which has only 1 hole for the valve (which has a rubber seal), all other spoke holes are covered with that TL tape to make a proper seal all around the rim. It is also important that TL tape to have a proper width, for example for 30mm internal width rim the TL tape should be 31-32mm wide because rim channel is not flat, but concave:

 

[Blakey]

Helpful thanks. So, if I get this right, the air is getting under the rim tape, and then escaping into the area next to the tyre and out from there?

Also, if I need to buy new tape, exactly which one do I need for this bike? Default set up? I can try and look this up but if there is someone with the exact same bike that can tell me, that would be very handy!

EDIT: The rim appears to be 30mm from a google, meaning 32mm wide tape?

 

[salko]

Yes

 

[Gallijam]

Just glad the new px comes ready for tuneless as the rim tape is already fitted

 

[Maxi]

Just glad the new px comes ready for tuneless as the rim tape is already fitted

The PL Pro came tubeless ready which saved a few ££ and a lot of hassle !