Bicycle Tutor

How exactly do you know if its time for new cables or not?

If the inner cable is fraying anywhere except at the very end AFTER it passes through the brake or derailleur, you definitely need new cables. Especially on the brakes where a frayed cable is dangerous.

On the outer housing, if you are seeing big cracks or splits, it's probably time. If your shifting isn't working well and the gear housing is splitting, a new cable and housing may fix the shifting issue.

If the cable no longer slides smoothly through the housing, you can try dripping some oil down inside the housing or take the cable out and regrease it. But if it is rusted to the point where it still slides rough, time for new cables and housing.

You don't need to go crazy and buy the super expensive stuff. But note that bargain basement cables and housing do not work as well as mid-range stuff. Your brakes will feel crisper and your shifting should be more precise with decent quality cables.

ok thanks, now are brake cables and shifting cables one in the same? Or are they two different things?

no, brake and gear inner cables are different. In fact, road bike and mtn bike brake cable are different. There are even a couple different kind of gear cables. But most modern bikes use one type. The way to tell all these apart is to look at the piece on the end that goes in the brake lever or shifter. Make sure to ask for the right thing when you buy.

On housing, you can use brake cable housing for older, non-indexed gear systems fine. But for index systems, you should get SIS style housing made just for gears.

The advice from my LBS (J.E. James, Sheffield), says you should not mix brake and shift cable outer cables (restraints). I believe brake cables are somewhat (slightly) thicker than shift cables and this is the reason not to mix…
However, having said that, I can’t see why brake outer housing will not work with shift inners. Just don’t use shift outer restraints with brake inners on your brakes for what it’s worth (I’m sure it’s been done by someone somewhere)…

Brake housing (outers) are made to handle large forces without bursting to handle the force you put on the brakes. If you look at the metal part inside, it looks like a tightly wound spring. The "weakness" of this design is that under pressure the housing compresses a little. Higher quality housing will have less of this compression as the 'spring' is wound tighter. That is fine for brakes. However, on index shifting, that compression will mess up the precise adjustment the shifter needs to move the derailleur to the proper position. If your bike has very short length of housing for the shifters (like on a road bike with frame mount shifters) it probably won't make much difference. Also on older bikes with 6/7/8 speeds, the steps between the gears are larger so a little housing compression won't hurt.

Shifter housing has the wires in the housing (not the shifter inner cable) running parallel to the length of the housing. That way, it won't really compress until load. However, under the high pressure like you get in braking, the sides can burst.

So, may be ok to use brake housing for shifters, but may cause trouble getting your shifting adjusted right. But gear housing for brakes is dangerous.

Well said DaveM, thanks for the explanation...
Marc Dominic.

So is it possible to buy rolls of the different types of cables? I restore bikes often and new cables and housings are one of the things I have not been replacing and I would like to start doing that. And what exactly is the difference between shifter and brake inner cables. Are they different types of wire/metal or different strengths?

Thanks guys.

http://www.sjscycles.co.uk/product-Shima...http://www.sjscycles.co.uk/product-Shimano-Shimano-SIS-SP41-4-mm-Black-Outer-Gear-Cable--Workshop-Roll-Of-10
http://www.sjscycles.co.uk/product-Shima...http://www.sjscycles.co.uk/product-Shimano-Shimano-SLR-M-System-5-mm-Brake-Cable-Outer--Grey--Workshop-Roll-Of-30
http://www.sjscycles.co.uk/product-Shima...http://www.sjscycles.co.uk/product-Shimano-Shimano-SLR-M-System-5-mm-Brake-Cable-Outer--Grey--Workshop-Roll-Of-30

Just 3 off Shimano's range. There are other makes such as Gore so just do a search. The one thing is Shimano cables are very hard to cut and you could do with the correct tool. Again check out the various on-line shops or your LBS.

Awesome, thank you kindly.

My LBS supplies me with standard inners for brake and shift (they’re not branded i.e. I buy them loose and they come without labelling but I think they’re Specialized brand – but I could be wrong). Outters for brakes are JagWire which is reasonable at £5GBP ($10USD in the current economical circumstances!) a metre (meter US talk).

Agreed you need a good tool to cut them. Plus, just for the appearance (and to be hassle free – after all they’re cheap) fit new shiny (silver in colour) ferrules…

Job’s a good ‘un…

So do the park tool cable cutters work better than just a standard pair of wire cutters I might have in my tol box? I was lookin on ebay for a pair of those and also the 4th hand tool.

You don't want standard electrical wire cutters for bike cables, since the bike cables are thicker/stronger than standard electrical wire and you're likely to fray and tear them up when you try to cut them more than be cut. You want a crisp clean cut when you work on them.

And standard wire cutters are out when you want to cut the outer housing since they're guaranteed to work rather poorly.
I can't speak to the quality of Park with respect to this tool, but I will say that when I read about this topic, most tend to recommend Shimano. YMMV of course.

OK thanks, I'm still trying to pick up some of those tools

Jordan,
I mentioned that you need a ‘good tool’ to do the cutting job, especially on outters. I personally do use a set of wire cutters but they are heavy grade (not your average domestic), that I borrow from work. Try your existing cutters in a test to see how they perform before forking out a (small) fortune on specific kit. The key point with outters is getting a proper right-angled cut with no protruding outter wires that will affect shifting and possibly braking (although the forces involved are higher here). I usually fit new ferrules too…

ok, I'll see what i can figure out, I just took apart an old Trek 4300 to work on this month, so I'll practice some cuts on those old cables and see what my results are.

Can you refer me to higher quality brake cable housing with better (less) compression and higher quality brake cable less likely to stretch?

The link up above will take you to the shimano cables that I got. They seem to work really well.

Hey folks,

If you truly want the best cable housing, try Vertebrae Ceramic housing (http://www.vertebr.ae). I've been using the same set (the initial prototype!) for the past three years - with no issues.

While it is not cheap due to the costly materials involved, they offer *outstanding performance and longevity*. You'll never need to buy housing again (just some replacement liner and cables when the need arises). Yep, it's the sort of stuff you can take from bike to bike. I like to think of them as "the Chris King of cable housing..."

Hoping to get a few sets on some of the show bikes at either Eurobike and/or Interbike later this year...