Have some Crest rims that I am wanting to setup tubeless. They are well used and have some damage around the valve hole i.e. the hole is now bigger than normal and it has an irregular shape.
I was thinking of applying the yellow tape as normal, making a hole, cleaning up the hole with a round file and then applying silicon sealant around the valve stem to attempt to seal the gaps.
Any better ideas? (apart from use a tube!)
The superstar/wtb valves with the bigger conical base are very unfussy- I had a set of olympics that'd been badly drilled out for a rim strip and they worked fine on that, frinstance. You can get the same effect with some tube valves.
Sealant will do it but it's potentially a pain if you get a puncture/want to remove the valve I think.
A section of inner tube and push the valve through should work, and leave the valve easilly removable if required. Schwalbe procore actually uses those clear square instant patches over the valve hole to push the valve through to provide a better seal around its base, they really help, will be doing that next time I do a set-up on normal tubeless.
I would use a patch over it and conical valves and i think it will be fine
ok, cheers guys, i'll try cutting an old tube
Joe's noflats (and probably many others):
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I had an Easton Haven with the same issue and changing to the Easton Valves rather than whatever generic ones I had worked for me. They had a a larger rubber bit on the inside that as long as the locking ring was tight on inflation filled the chips/cracks nicely.