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On Sun, 12 Sep 2004 16:59:30 -0400, "Chuck Davis"
wrote: wrote in message .. . ..... As for valve extenders, I found them so annoying that I switched to long valve stems after fooling around with teflon tape to seal the threads. Another problem is that the extender is just a hollow shell that fits down over the real Presta valve, whose lock-nut must be left unscrewed, leaving nothing but air-pressure to seal the valve. In addition to the obvious problem of losing air-pressure without a lock-nut, the extender makes it hard to break a stuck valve free. This can cause two problems. First, you can't pump the tube any further if the valve sticks on a mostly-filled tube. Second, you can't let the air out to collapse a slow-leak flat to remove the tire. So you have to remove and replace the extender, an awkward job, or else carry something to poke down into it to free the hidden Presta valve. In general, most small adaptors, extenders, and adjustable devices fail to work as well as the real things whose specific purpose they are meant to imitate. Carl Fogel If you use an extender such as: http://www.worldclasscycles.com/valv...nsion_tube.htm you'll find that they have a valve control that allows you to open and close the valve. The metal extenders do need an O-ring or Teflon tape for a good seal on the valve, but plastic versions of this type of extender will seal as is. Chuck Davis Dear Chuck, Assuming that they work, those valve extenders add a nice feature, but at $26 plus shipping for a pair of 50 mm extenders, I'd be looking for tubulars with long stems if I used tubulars. If you know where to find the easier-sealing plastic version of these valve-extenders with valve-controls, I imagine that some tubular enthusiasts reading this thread would be pleased to see the link. Carl Fogel |
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Tufo tubulars don't come with long valves. They have the removal valve nut,
and you remove that, put their extender in there via screwing in using the valve threads on the inside of the tube valve and screw the presta valve insert into the top of the extension. works marvelously - no teflon tape required. david |
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wrote in message ... On Sun, 12 Sep 2004 16:59:30 -0400, "Chuck Davis" wrote: ........ If you use an extender such as: http://www.worldclasscycles.com/valv...nsion_tube.htm you'll find that they have a valve control that allows you to open and close the valve. The metal extenders do need an O-ring or Teflon tape for a good seal on the valve, but plastic versions of this type of extender will seal as is. Chuck Davis Dear Chuck, Assuming that they work, those valve extenders add a nice feature, but at $26 plus shipping for a pair of 50 mm extenders, I'd be looking for tubulars with long stems if I used tubulars. If you know where to find the easier-sealing plastic version of these valve-extenders with valve-controls, I imagine that some tubular enthusiasts reading this thread would be pleased to see the link. Carl Fogel Carl, You can find the plastic version on one of my rear wheels. The only link pointing to it is part of my chain. 8) I bought the extender in 1997 when I bought a Spinergy wheel. I looked for plastic extenders again lately and was only able to find metal extenders (with the core I mentioned.) Yes, they do work and they work quite well. I found them at Nashbar for $9 each, but they're not listed there anymore. I ran across this interesting tip at http://www.bookcase.com/faq/bicycles-faq/part3: "Another tip.For those with deep dish rims requiring valve extenders, place a small amount of loctite on the tube valve stem threads and then screw the valve extender on. This will prevent any leaking at that junction once the tire is glued on." As I think about it, it seems that a little Loctite on each valve would be enough to get a seal for each tire or tube that you have. If you want to save money, you could get ONE metal extender with the core and a plastic one without. Use the plastic one to inflate the tire and use the metal one to close the valve. In that case, you won't need any seal for the metal extender. Chuck Davis |
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On Sun, 12 Sep 2004 20:48:36 -0400, "Chuck Davis"
wrote: wrote in message .. . On Sun, 12 Sep 2004 16:59:30 -0400, "Chuck Davis" wrote: ........ If you use an extender such as: http://www.worldclasscycles.com/valv...nsion_tube.htm you'll find that they have a valve control that allows you to open and close the valve. The metal extenders do need an O-ring or Teflon tape for a good seal on the valve, but plastic versions of this type of extender will seal as is. Chuck Davis Dear Chuck, Assuming that they work, those valve extenders add a nice feature, but at $26 plus shipping for a pair of 50 mm extenders, I'd be looking for tubulars with long stems if I used tubulars. If you know where to find the easier-sealing plastic version of these valve-extenders with valve-controls, I imagine that some tubular enthusiasts reading this thread would be pleased to see the link. Carl Fogel Carl, You can find the plastic version on one of my rear wheels. The only link pointing to it is part of my chain. 8) I bought the extender in 1997 when I bought a Spinergy wheel. I looked for plastic extenders again lately and was only able to find metal extenders (with the core I mentioned.) Yes, they do work and they work quite well. I found them at Nashbar for $9 each, but they're not listed there anymore. I ran across this interesting tip at http://www.bookcase.com/faq/bicycles-faq/part3: "Another tip.For those with deep dish rims requiring valve extenders, place a small amount of loctite on the tube valve stem threads and then screw the valve extender on. This will prevent any leaking at that junction once the tire is glued on." As I think about it, it seems that a little Loctite on each valve would be enough to get a seal for each tire or tube that you have. If you want to save money, you could get ONE metal extender with the core and a plastic one without. Use the plastic one to inflate the tire and use the metal one to close the valve. In that case, you won't need any seal for the metal extender. Chuck Davis Dear Chuck, This is probably not the best time to mention that I have for years harvested nice metal Schrader valve caps with the built-in valve-core wrench from a friend's motorcycle, often right in front of him when we're checking motorcycle tire pressures with the machines on the trailer. (The caps come off quit easily and look much better on my tubes than on his.) Let's hope that no one admires your 1997 plastic extenders enough to follow my evil example. Carl Fogel |
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