ok singletrackers – kudos to anyone who has the wherewithall to reply to another tubeless question

i've just installed the yellow rim tape on my stans 355 rims, pluged the valve stems in, fitted tyre – tyres pumped straight up, but air pi**es out from where the valve stem sits.

takes the tyres out and had a good look at the valve stems, they just don't seal – where you have the u shape inside the rim, the valve doesn't fit into it leaving a gap

am i an idjiot – if so please point out what i'm doing wrong

otherwise, lifes too short – i'll just chuck in tubes and ride, bit galling when apprently tubeless is the next best thing ;o)

There is more than one valve that they do – I assume you have the right one?

I'm about to do something similar with Flow's soon so I'll just watch any more helpful answers that come in if I may.

you have the valve with the small rubber gromit like this

you just have to tighten the collar up so that the rubber forms to the inside of the rim. It can be quite stiff to get it air tight I use pliers on the collar GENTLY!

Captain, you need the olympic valve for the 355 rim. Checking justridingalong.com, it seems thats the only one!

I found that with making the hole in the rimtape for the valve, you cant really make it too big. The tape is there to stop air leaking through the spoke holes.

Edit: the olympic valve has a smaller rubber gasket than the one pictured above

the standard will fit a 355 rim no hassles I have them in mine. I only have olympics valves in the olympic rims because the internals are narrower.

assume i have the right one, supplied with hope hoops, it has a foam ring rather than the rubber one in the pic above (think that might be the problem) – i'll go and grab the pliers but don't think it will do any good (tightened it as hard as possible by hand)…

just checked – i have an olympic stem – but there is a visible gap, weird

i'll take them to the LBS where i got them (see – that's why bike shops rock, you can let them head scratch and fix, while you drink there coffee)

Had the same problem but did manage to get it sealed in the end. Trouble was whenever I had to put air in I would disturb the valve and it would p**s air. Didn't install a lot of confidence and could see myself stranded somewhere with flat tyres so gave up in the end and fitted the rim strips and i've never had a problem.

Did you put the yellow tape on **** tight, after keying the rim etc?
The air might be coming out from the valve, but that's not necessarily where it's coming from.

As well as the rubber base of the valve that sits inside the rim/tyre there should be a rubber washer/ring that goes on the outside, underneath the valve nut. I think the main seal is inside but this ring must help. FWIW I got my Olympic rims to inflate using just valves and yellow tape but I do use alot of JRA's wheel milk to seal the whole thing up.

My rims, 355 with stans olympic valves, as recommended by JRA.

Same as Burls, I had air leaking from the valve. Whenever it got knocked or pumped up, it would spring a new leak and have to have a shake and re-seal. I've used a splodge of glue to take up the gap. General purpose stuff that fills the gap nicely and won't be too sticky if I have to pull the valve out for an emergency. I might try the next one with silicone seal.

like these
http://www.justridingalong.com/files/wheel_parts/notubes_UST.jpg

As well as the rubber base of the valve that sits inside the rim/tyre there should be a rubber washer/ring that goes on the outside, underneath the valve nut. I think the main seal is inside but this ring must help. FWIW I got my Olympic rims to inflate using just valves and yellow tape but I do use alot of JRA's wheel milk to seal the whole thing up.

ok – i've put in an additional 1" section of yellow tape around the valve stem and just made a slit and pushed the valve through – then tightened up with some pliers (carefully!)

I originally installed the yellow tape as shown (keyed in with fine sand-paper, cleaned with isoproypl alcohole, pulled the yellow tape as tight as possible, installed the tyres with tubes to get the tape sealed right.

just pumped them up, and they are full of air – not going to pop the champagne cork yet, i'll report back in the morning…

damn – there flat, put some sealant in as well

hurumph