Installing cable splitters
 

I'm putting Ritchie cable splitters on my S&S coupled bike (not a tandem, but figured there would be experience here wit S&S coupled tandems)

http://www.excelsports.com/image/Rit...ail%20Pair.jpg

I'm using Dura Ace cables. I thought I could just cut the cable in the middle and attach.

However it appears that you need to have a head on the cable at one side of the splitter.

Given that the DA cables only come with a head on one end, do I have to use 2 cables to make these work, or am I missing something?

Yes, splitters require two cables...

A good thing for tandems since it eliminates the need for tandem-length cables, but not so much for single bikes.

thanks.

Generally you need derailleur cable-type heads for the splitter, btw. Sometimes I'll hang onto rear derailleur cables that I've replaced due to end fraying, cut them back a lot, and use them as the "second" part of the cable-splitter setup. But, I'm cheap.

Also, as I've posted previously, be sure to check the little set screws regularly, especially when new. I've done this religiously since the time I squeezed my brake lever only to have the cable pull out of the splitter because the set screws loosened up.

put superglue on the cut end of the cable that goes into the splitter, and let dry well before installing, it helps the cable not to fray

Cable Fray Fix
 

Even better than superglue, try mixing up a dab of JB Weld or JB Quick. Not only does it totally prevent the cable wires from ever fraying, it leaves a nice, round, smooth finish that won't scratch or get hooked on anything.

most splitters accomodate either derailleur or brake cable heads. Generally after you have tightened a cable in the splitter it is hard to reuse the cable as it gets deformed and wont feed through housing unless you can shorten it. Because of this not much need to super glue or JB the ends as they are completely contained in the splitter. Be carefull backing out the set screws because if you drop one it is almost impossible to find due to their small size (you can guess why I know this!).

just a little solder works well on cut ends...

^ Silver solder^ wipe while hot to clean it and it will still slide into the housing with no trouble also.
If you do this before you cut cables you can use any cutter and it will be a nice clean cut.