Bicycle Mechanics - Coupling 2 pieces shifter housing?

I have a triathlon bike that has complicated shifter housing routing and the housing is too short.

Can I attach two pieces of shifter housing via a metal sleeve? Perhaps 2 inches of tubing on either end of the connection?

I figured, shifter housing has not too much stress on it.

searched and couldnt find the answer
thanks
Jeremy

as long as there is not a kink in the cable where it is coupled, i don't see why not...

Yes and no. It's doable, but has to be done right.

First of all the ends need to be cut square, or ground square after cutting. Next the two ends cannot simply be butted up against each other because unlike a typical brake housing where the coil will provide good support, index housing is like the end grain of wood, and the two sections will try to settle into each other. You need to insert a metal washer between the sections to prevent them from meshing. If you can't find a small enough washer buy the smallest you can find, and thread it onto a spoke to spin grind the OD to size.

For the tubing, you should be able to find a section of stainless or brass tubing the right size in a hobby shop.

BTW- as a simple alternative, buy an inline adjuster and use it for the splice. You'll get a good splice, and an added range of adjustment as a bonus.

something like this? Crazy enough to work! kidding

http://www.benscycle.net/index.php?main_page=product_info&products_id=3632&currency=USD

there are double ended ferrules for housing , thru
QBP of course, there is a shoulder in between so more than just a tube.
early aero brake lever D A kits included some
so no untaping the bars was needed to replace the exposed part
of the housing.. ferrule was to be just at the end of the tape.

and you can use an inline cable adjuster,
which may come in handy dealing with a long cable run ..
Jagwire thru your LBS, another QBP item.

I don't doubt the above instructions which would give a perfect splice. I like the barrel adjuster as quick and functional.

That said, I once did it by simply butting the two pieces of housing against each other and taping securely. It worked fine, I couldn't ascertain any functional degradation. Not to say others wouldn't, but I didn't.

Any bike shop will have double ended ferrules. They will cost about $1 or less. You may also consider to put in a longer cable as well. The double ended ferrule is by far the best solution. The inline adjusting barrel will cost closer to $5+. The cable housing ends regardless of which way you go need to be cut and prepped to insure smooth cable action.

I've used purpose-built housing splicer "ferrules" many times. One thing is that all of the ones I've come across were for 5mm OD housing, i.e. brake housing (or older-school 5mm SIS housing).
They were chromed, had an internal divider, and about 1" long. Can't remember the source.
Campy's shifter housings are 4.5mm dia and Shimano's (and everyone else's) usually 4mm these days.

Housing is like what? a buck a foot in bulk at the LBS? I'd just buy the length I needed and forget the splice.

Housing is like what? a buck a foot in bulk at the LBS? I'd just buy the length I needed and forget the splice.

The splicing is usually done in order to spare one from having to re-wrap the bar tape. When I've used a splice either I had replaced the stem with a longer one or was moving the entire handlebar/levers/cables assembly from one bike to another. The splicers saved considerable effort in those cases, especially when the bar-wrap is somehow special, i.e. "woven", sewn-on, etc.. Bar wrap is a finishing touch that some people put considerable effort into.
Also, many shops charge well more than a buck a foot for custom-cut lengths, even rounding-up each length to the "nearest" foot!
I've seen a bike's-worth of housing go well over twenty bucks for generic black housing.

Housing is like what? a buck a foot in bulk at the LBS? I'd just buy the length I needed and forget the splice.

No doubt. The time I did a splice was on a weekend when I was modifying a bike that had the inline brake levers - I wanted to remove the levers for some reason and just spliced the cable housings rather than make the 45+ minute round trip to the bike shop for cable housings or a splicing ferrule. I think I replaced the inline levers fairly soon after that, but didn't have any issues in the mean time.

When you think of how the housing physically works to lend structure to the cable, it really isn't hard to see there's a bunch of ways to splice or splint it while maintaining adequate structure and function. But like you said, there's no cost-based reason not to replace the housing, but there are a lot of convenience-based reasons to make do somehow.

Campy's shifter housings are 4.5mm dia and Shimano's (and everyone else's) usually 4mm these days.

And wrong.

Campy shifter housing is now 4.1mm.

One thing is that all of the ones I've come across were for 5mm OD housing, i.e. brake housing (or older-school 5mm SIS housing).
... Campy's shifter housings are 4.5mm dia and Shimano's (and everyone else's) usually 4mm these days.

A thin strip of tape (masking, celophane, etc) on the housing to build it up will take care of that problem.

There are proper ferrules for any available housing, and most all packages come with them.
Gotta hand it to Campy, they corner their own market on consumables. You name it, right down to their $22 replacement spoke.
But go to the Interbike show and they'll no doubt waste your time telling you why 4.1mm housing is better than industry-standard 4mm.

I love working on Campag bikes, grinding cable ends, wrapping housing with tape, etc.

Yes and no. It's doable, but has to be done right.

....snip.....

BTW- as a simple alternative, buy an inline adjuster and use it for the splice. You'll get a good splice, and an added range of adjustment as a bonus.

^^^^^^correct^^^^^^