Re: Throttle cable housing shortening . . .
Aleman and I usually agree on most things but I'll offer an alternative here.
Cutting the housing with side cutters, or dikes, can crimp the steel case shut which can be a bugger to reopen. I use a Dremel with a cut-off wheel then sand the end where I cut it to take off any small burrs. After cutting make sure the cable slides easily through the housing where it was cut.
Making cables and housings the right length can be a challenge if you don't completely understand the way a cable works. The housing as well as the cable must be the right length or you'll have slack or it will be too tight. A little experimentation will help.
Cable housing ferrels are available at most any bicycle shop. They come in metal or plastic. Most are standard size. Some require a tool to crimp them on, some are simply pushed on to the end of the housing.
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