Hey,
The valves are leaking at the hole in the rim. Using an airshot the air goes in and then when pressure builds, air starts to hiss out of the valve hole.I put a piece of inner tube inside the rim to try and create a seal but no joy. Still leaking - less so but still leaking.
Are these valves known to leak? Never used them before.
Can anyone recommend other vales or is there a better solution to making them work?
Cheers for any help.
Tried the piece of inner tube trick before, and its hit and miss.
If you have any silicon sealant then put a bit on the hole and around the valve, let it set, and you should get a good seal.
*edit - it's also worth checking your tape, as the air will always escape via the valve hole even if it's getting into the rim elsewhere.
I just tighten the valve lock nut up with pliers...good solid seal and haven't managed to mangle a rim yet!
Have a look at Mr tubeless on Facebook. Valves are blooming great have a little o ring in them and flats for a 9mm spanner on the lock nut. Totally bomber without any faff
Usually it's not the valve. Probably the tape has lifted somewhere and the air is escaping via the valve hole. Take it all off and have a look.
I pressed the rubber seal part of valve down with a plastic tyre lever so I could tighten it up proper tight.
That helped.
The valve nut should only be finger tight. No need for any more, unless the tape is knackered elsewhere and you are trying to stem the flow of air coming from under the tape.
It'll be the tape.
The valve nut should only be finger tight
I used pliers once, pulled it through the rim to stop it leaking.
Cheers for all replies.
@yak. I may be being stupid here but why would the tape lifting mean air would escape through valve rim hole? I.e. surely the air will escape under pressure through any hole possible, so if there is a gap in valve hole it would leak air irrespective of rim tape issues?
Also, they're new wheels with rim tape already fitted. Maybe I need more rim tape?
edenvalleyboy - Member
Also, they're new wheels with rim tape already fitted. Maybe I need more rim tape?
Rim tape or tubeless tape?
tazzymtb - Member
Have a look at Mr tubeless on Facebook. Valves are blooming great have a little o ring in them and flats for a 9mm spanner on the lock nut. Totally bomber without any faff
make sure you are carrying a 9mm then 😉
As above, did it come with tubeless rim tape or standard? It’s pretty easy to damage rim tape with tyre levers and regardless of where the damage is, the air will escape from around the valve hole
Yes, if air escapes into the rim cavity via lifted tape, then it will come out via the easiest route. Possibly a bit via spoke holes, but the biggest hole is the valve hole, hence seeing air here for almost all leaks that are not directly from the tyre. So it could be the valve, but the rubber cones at their bases seal easily, or the valve core is loose, or something else like the tape. The tape is fragile and is the weak link in the whole tubeless set up. Give all the above a check, but just cranking the valve nut really tight is not the answer. You might have to remove it on the trail too at some point.
I may be being stupid here but why would the tape lifting mean air would escape through valve rim hole?
The air will take the path of least resistance, which in this case is the valve hole. The spoke & nipples do a pretty good job of sealing the spoke holes.
So the rims are tubeless ready? All that means is they can be set up tubeless, not that they're ready taped!
If you haven't taped them yourself, then suspect that is your issue.
I've seen this problem on 2 mates new bikes. They assumed tubeless ready meant ready for tubeless...not so!
And buy Tesa 4289 tape around £9 for 66m,as good as Stans and about 1/10 the price !
Encountered this same problem when swapping my friends tyres last night. Quick jiggle of the wheel seemed to sort it out, maybe sealant filled the tears or damage to tape? Hopefully he doesn't find the tyres flat next time he goes for a ride....
Managed to get them setup up tubeless and ridden on fine.
Cheers for all the help.
+1 on the leak through the rim cavity.
I got a puncture on a ride and it was leaking out the valve hole and wouldn't seal. Couldn't work out what was going on, until took off the tyre and found a huge nail had gone through the tyre on the other side of the wheel and through the rim inside (carbon swiss cheese rims), creating a hole into the cavity and air then out via the valve hole as the valve isn't actually sealed on the outside.
