Bicycle Mechanics - cabling questions...

when installing new cables, should you use the cable stops on the frame? or is it ok to run the whole length of the cable in the housing? are the benefits either way, like less dirt getting in the cables?

thanks!

later

You run housing only where you need it, i.e., at curves and bends which is usually defined by the presence of cable stops. Otherwise, you want your shifting cables exposed. Housing adds weight, bulk and invites yet another place for dirt to gather and create friction.

Manufactures continue to chase alternative systems such as air (Shimano) and electronics (Mavic & Campagnolo) to replace the archaic but relatively cheap and efficient cable shifting systems but none have succeeded in making them cheap enough and -- in the case of electronics reliable enough -- to make cables and housing obsolete.

Hydraulic lines for brakes are very efficient but, again, add complexity, weight, bulk and expense that haven't yielded enough benefit to replace the cable actuated brake systems.

Housing adds weight, bulk and invites yet another place for dirt to gather and create friction.

how much weight can housing really add? if you're just a hobby rider will the weight difference matter all that much?

wouldnt it be harder for dirt to get in if the entire length of cable was covered?

not dissagreing with ya, just a newbie learning the whys and hows of things. thanks!

later

The problems could see, is the cable stops are there also to hold the cable. So now you would have to use tie wraps or something to hold it in place. And then when the cable gets to teh bottom bracket you would have to cut it run it down underneath if does not go along the top, and since no cable stop their would get ALOT of dirt crammed up in their and would not fit properly.. if run along the top you would have similiar issues. Alot of good cables now have ferrules specificaly designed to keep dirt out.

thanks for the info. and you can get ferrules at the LBS? or another online bike shop?

later

Your LBS should have ferrules. If not, most of the online vendors will have them, including:

Loose Screws (http://www.thethirdhand.com/index.cgi)

and

Bike Tools Etc. (http://www.biketoolsetc.com/index.cgi)

hopefully my last question until i actually get to do this job. any recommended brands or such?

later

Nokon makes a beautiful set of cables :)

Other then those, aztec, gore-ride on.. both make excellent cables. They will come with the ferrules no need to purchase them separetely.

Originally posted by Aemon_
how much weight can housing really add? if you're just a hobby rider will the weight difference matter all that much?

It's not just weight; you have:
1. Added bulk: something else that needs to be secured to the frame so that it doesn't rattle around, scuff the paint and detract from the frame's clean lines.
2. Added friction: Regardless of how slick the housing is, the more surface contact you have between the cable and housing the more drag there is on the cables. A cable running through the air encounters no measureable friction.
3. Added cost: You add something to the bike like 3' of cable housing then the price of the bike goes up.

All for something that doesn't pose much a problem for a properly assembled and maintained bicycle.


wouldnt it be harder for dirt to get in if the entire length of cable was covered?

Sure, but you assume this is a major problem and I'm suggesting that it's not, otherwise an alternative solution would have already replaced it. Yes, there are gore-tex cables and other pricey alternative systems that can out perform standard stainless cables and housing. But, then again, at $1.50 a cable is a pretty cheap part that's easy to clean and replace.

If you're really interested in sealing up the ends of your cables consider something like http://www.csferrules.com/

There are pros and cons to each system, but I prefer to leave the cables exposed, if only it is because the bike is set that way.

Pros for exposed cable

- A bit less friction. Good cable housing doesn't add too much friction, especially for straight sections; still, no housing means even less friction.

- Housing is compressible (a bit). Even SIS housing compresses a bit. It doesn't make a real impact on braking, but could do for indexed shifting.

- Straight lines are really straight. Exposed cable is under tension, therefore it always run in a straight line. Even with many ferrules or tie wraps, "housed" cable always curve a bit.

- Nicer, but it depends on the taste. Housing used to be available in many different coulours; now it seems to be only available in black, white (sometimes) and in a few fluorescent colours. Cables disfigure less a bike than housing.


Con for exposed cables

- Sections under the bottom bracket are rather vulnerable to grit, especially on a fenderless bike.

Regards,

You can only use outers in the lengths your bike frame permits. If your brake cable stops are designed for inners cables only, then between those stops you run the inner. Some older and touring style bikes have wider diameter cable guides designed for outers.
For all-weather bikes, commuters and tourists, as well as mud riders, there are advantages to running a continuous outer brake cable which can counter the slight performance hit. Mud can only enter a cable at the exposed ends.

Gear cables outers must be as short as possible, to maintain the precision of the cable pull for indexed systems.