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tried putting a bit more air in the tyres last night, and instead of the little bit on the end unscrewing, the cores started unscrewing instead.
id put the sealant in by unseating the bead, so id never unscrewed the cores before, they were as i bought them.
ok, i realised in time and screwed them back in, but when i tried nipping them up with small adjustable, it unsettled the valves from the rims, and broke the seal. air p*ssing out 🙁
is this a common problem? and how can i stop it from happening again? yes i can reseat everything and tighten up with a spanner, or buy a little 'core tool', but i dont want to be hamfisted and start tightening stuff so much it rounds off the flats on the cores or something.
is it a case of sealant drying in the valve, and making the little end bits stick? so the core comes out instead?
rims are stans 355, and im not sure if theyre drilled for schraeder or not. if so im thinking i should maybe have bought a couple of those 'schraeder to presta' adaptor things? to narrow the hole and make the valve more secure so it doesnt move?
anyone else had this happen to them? as i said, im using 355s, but non tubeless tyres, an ardent and little albert. no rimtapes, just yellow tape and valves. i realise that rim tapes with valve included would solve this, but theyre a rip off at £40 a pair, and plenty of people seem to do fine without them. spose i could ghetto tubeless them and use half an inner tube, but its all worked fine so far, just this little problem now.
cheers
Hold the core with the little plastic tool while undoing the press valve.
£40 a pair of rim tapes with valves are not that much of a rip-off surely?
I put a bit of silicone grease on the valve core to help prevent the sealant sticking to it & it doing what happened to yours
Scwalbe tubes have removable valve cores, but one then take the core out?
£40 a pair of rim tapes with valves are not that much of a rip-off surely?
I think they are, there's nothing in them to justify the cost, they're simply charging it because they can
Ghetto all the way for me
It's perfectly normal and your doing everything right.
The knurled valve nut can sometimes get a little clogged with sealant or the pin can get slightly bent from hamfisted pumping. In this case as you say the valve will come appart as you unscrew.
Uplink's idea of silicone grease is good to stop it happening, and the £5 for the red Stan's tool is money well spent ime compared to a mini adjustable for nipping the valve-core back up nice and tight.
It's just one of those things.
I find to get the valve assemby nice and tight to the rim, it helps if you pull on the valve as hard as you can whilst tigtening the lockring. I've never had a whole valve unscrew before like you describe.
no, the whole valve didnt unscrew, just 'move' a bit, so breaking the seal and leaking air.
yup, i think if im going to stick with this tubeless lark, then ill invest in the proper tool for the cores. bit of a pain with an adjustable, with spokes getting in the way.
silicone grease is a good idea yep. altho rather than on the core (which isnt sticking), would i be better off putting any under and around the knurled valve nut? as thats the bit thats sticking.
fauxbyfour, you dont consider £40 a rip off, for whats basically a pair of split inner tubes??? or is there more to it that that. cant see what to be honest :-/
thanks all. comforting to know im not the only one, and its quite common 🙂
Mr. Punk
Assuming your valves are similar to the ones I got from JRA I just nipped my valves us nice and tight with the knurled nut to get the rubber on the back to seal tight then gave it a wiggle and tightened up a bit more a few times. It might be too tight to undo by hand on a cold day but that's what small pliers (or a leatherman) are for should tyres fail on a ride.
Failing that you could try putting the valves in with a bit of silicone seal around the edge to seal it securely.
Anyway I agree the rims strips are a rip off. I paid enough for a core remover and sealant injector but I won't pay that.
Even if the core came all of the way out it shouldn't break the 'bead'.
While I agree the Stans rimstrips are expensive, a standard Mavic removable core valve isn't cheap. The rimstrips do though give you a more 'stable' setup with less leakage.
I now don't bother unscrewing the core, but just break a bead to get the latex in, once I've got the tyre seated properly - a compressor helps here 😯
TBH while I have some standard rims and Stans rimstrips, I prefer UST rims (819's), and use with either UST, standard or tubeless-ready tyres.
You're not having much luck with all this are you. Are you being paid by inner tube manufacturers to make tubeless look really difficult? 😉
Because you never removed the core originally I'd say it was always a bit loose. Just nip them up firmly (don't go crazy) while holding the stem with a pair of pliers.
I just do them gently with a small pair of pliers.
You should be grateful you have the removable cores - much less faff than pouring sealant in before seating the rim!
I use a plastic medical syringe to squirt into the valves btw.
I have tubeless which I inherited from the guy I bought the bike from. Now after six months I think the sealant is drying up as the tyres keep slowly deflating. I noticed the presta valves knurled nut thing are stiff and I need pliers to release before pumping up each time.
Which is the best way to get more sealant in? through the valve core by unscrewing it or break the seal on the rim?
I am a complete newb as regards tubeless BTW...
break the rim seal
also the knurled nut should be stiff, its providing a 'seal'
TBH your best bet is to take the tyres off, and understand what tubeless setup you have - then re-install
I unscrew the valve core and use a syringe - bought a load of em off ebay cheap, very handy for this and fork servicing etc. I also got the Stan's valve core remover tool, which is nice, though pliers work fine as well.
ok will do..i have some spare sealant so I suppose just squeeze some more in there and re-flate
Assuming your valves are similar to the ones I got from JRA I just nipped my valves us nice and tight with the knurled nut to get the rubber on the back to seal tight then gave it a wiggle and tightened up a bit more a few times. It might be too tight to undo by hand on a cold day but that's what small pliers (or a leatherman) are for should tyres fail on a ride.
thats exactly what i did. are you using presta valves in a schraeder sized hole? or using adaptors to make it a better fit?
Failing that you could try putting the valves in with a bit of silicone seal around the edge to seal it securely.
tis a good idea. defo going to try a bit of that. think ill probably buy a couple of those adaptors first as well to make a better fit. theres rubber grommets, and metal adaptors. any advice as to which are better?
You're not having much luck with all this are you. Are you being paid by inner tube manufacturers to make tubeless look really difficult?
im getting there. slowly but surely. tis a learning curve 🙂
Because you never removed the core originally I'd say it was always a bit loose. Just nip them up firmly (don't go crazy) while holding the stem with a pair of pliers.
id say thats probably about right. altho them being too loose wasnt the real problem, the problem was the knurled end bits having got stuck, so the cores unscrewed instead. knurled ends really took some shifting :-/
so.........next step is buy a couple of schraeder to presta adaptors, and a core spanner. then let air out, probably put a bit more sealant in and this time hopefully inflate for good 🙂 ill keep the beads seated and use my syringe.
hopefully i wont have a problem as long as the knurled valve end doesnt get gunked up and stuck again.
cheers
This is a very funny thread indeed. All the above palaver about removeable core this and knurled nut that, sealant here and grease there. And for the sake of £20 per wheel you are faffing around like headless chickens not being able to get the most simple of set-ups working. Just spring for the £40 quid and then you'll realise it was money well spent.
sadex - they're stans 355 rims built on to Hope Hoops. bought 2nd had so I don't know if they've been drilled out to take a schraeder. I didn't notice that they seem large holes?
I did the first wheel monday and it was nicely sealed up by wednesday. No more losing pressure, all the (many) holes sealed up. The second wheel was done this weekend and was losing air around the valve, but adding more air and shaking to get the gap covered in sealant seems to have done the trick. All in I've done maybe half a dozen gone-down-so-add-more-air-then-shake-to-seal jobs on each wheel.
All the above palaver about removeable core this and knurled nut that, sealant here and grease there. And for the sake of £20 per wheel you are faffing around like headless chickens not being able to get the most simple of set-ups working. Just spring for the £40 quid and then you'll realise it was money well spent.
NO!!! rip off. principles 🙂
I use two links from a chain to tighten/undo the Stan's style valve cores with flats. If you take a bit of chain so you have two links (i.e. three pins) the distance between the plates fits perfectly and the other link gives you leverage to tighten it up without overdoing it - and doesn't catch in the spokes.
Genius.
haha nice one. ill have a look at that tomorrow 🙂
Just spring for the £40 quid and then you'll realise it was money well spent.
Just as possible to have the same problem with 'proper' rim strips.