Silca’s new Presta valve extenders’ clever use of elastomers and sealants put an end to the annoying rattle inside the rim hole and prevent air leaks.
On the outside, an elastomer ring is designed to sit snugly inside the rim’s valve hole and hold it firmly in place. That prevents it from rattling around until your nerves are shot, and it’s a good sight more attractive than electrical tape. You’ll need to measure the distance from valve hole exit to the inner rim bed and figure out the difference between that and you current tubes’ valve length to make sure it all lines up, but your sanity is worth it.
On the inside, they worked with a company that specializes in thread sealing to coat the inner threads so they seal tightly against the tube’s valve threads. Then, they added elastomeric gaskets at both ends of the interface to further plug the joint. The result is no air loss. Or at least no more than you’d get with just the regular tube.
But wait, there’s more…
They’re available in two versions, the FVC (Fixed Valve Core, shown above) and RVC (Removable Valve Core, at top of post). The FVC threads over the stock valve, leaving the head twisted open to accept air. The top of the extension has threads, allowing it to be used with the current crop of thread-on floor and hand pumps.
The RVC threads directly into the stock valve and repositions the valve core at its top.
They both retail for $34 for package of 2 extensions. FVC comes in 45, 60 and 75mm; RVC comes in 34, 45, 60 and 75mm. The thread sealant is not a thread locking compound, so they say they’re reusable, too. Made in USA, available now.