Whats the difference in real world use between gear and brake cable outers? Can they be mixed and matched sucessfully?
Modern (SIS) gear outers are designed to maintain a fixed length when they flex, but they won't withstand the high loads of braking. Brake outers are incompressible under braking loads, but don't keep a fixed length under flexing. So basically they're not interchangeable.http://www.sheldonbrown.com/cables.html#housing
Some modern brake outers use an SIS-type design with an external Kevlar wrap to maintain the structure under braking loads. I guess you could probably use those for gears, but they're more expensive than SIS outers, so it wouldn't make a lot of sense.
Oh and if anyones got some spare white outers going cheap...
Think I've got some white SIS outers somewhere...
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