Are there any generic hose extensions for frame pumps? I see two kinds of portable frame pumps to carry with me on my riding:


Pmps that have a flexible hose that is either integral or pulled out and/or screwed on (e.g. Topeak Road Morph, or Lezyne).  The nozzle is at the end of the hose.
Pumps that have a nozzle that is right-angle to the pump tube, directly part of the pump itself.


The former are generally quite expensive, and the latter ones don't provide good leverage and are prone to bending the valve tip or coming off the valve while pumping, etc.

It seems so obvious to me that there should be a simple hose of, say 8 inches long, that would have a nozzle on one end to attach to the bike tube and the other end a fake Schrader or Presta valve head that the bike pump's nozzle would attach to.

However, I have not seen them online or in stores.  

This product, if it exists, would be able to provide a lot of the convenience of those fancier pumps at a fraction of the cost, not to mention it would be a generic way to upgrade existing frame pumps.  Of course, the extension should be able to handle the air pressure used for bike tires.

Can anyone tell me if they do exist and, if so, where I could get one, or what they are called?
Actually, yes, they do exist and are quite cheap.

The old stype frame pump, the very old style was just a stick with a straight shape. At the business end there was a threaded hole in wich you fitted the little hose. It was a arround 6 inches (15 cm) long, and had the propper head for the valve in one end, and in the other ussually had the same thread as the Dunlop Valve.

Here is the only picture I could find:
  

These pumps had a receptacle in the handle end, where the hose could be stored. There was a spring inside the telecopic handle, such as to dampen the hit at the end of the stroke, this also alowed you to "compress" the pump a little. The bike frame had a couple of "spikes" pointing at each other alongside some tube of the frame. So to store it you slide the hose inside the handle and inserted the pump between the spikes mentioned before, the pressure from the spring kept the pump in place. That is what you see in the picture, the longest, most shiny tube that is not being held, ia a pump stored in the green bike frame.

Those pump hoses are still available, and they look like this:


There are hoses threaded for Presta (Or Dunlop, it is the same threading) or Schrader. The end that attaches to the pump usually has dunlop/presta threading, so, if this end is long enough can easilly be used as an extenssion for a modern stick pump.

By the way, I managed to get the example picture by typing int the search term "bike pump hose" on eBay. There will be many different options, most are generic replacements for various types of pumps, but these small hoses usually are sold as "adaptors" so the word "adaptor" may be somewhere in the product name too. Use the reference picture to locate the type of hose you need.

If this option is not accesible for you at a reasonable cost, all the DIY aproaches are valid, but the easiest would involve a replacement hose for(from) a cheap pump. A very easy trick for the hose to pump fitting would be to source a good valve stem from an otherwise unusable inner tube. Use the one you like the most (Schrader or presta).