Routing rear brake cable outer housing around seat post

[Shut Up Legs]

I've just replaced my brake pads, and am having trouble with the brake cable's outer housing where it goes past the seat post . Normally, brake pad replacement is an easy enough job, but I'm wondering if the cable outer is curving too tightly. It's currently like this:

I've noticed when I apply the brakes, the cable doesn't slide as freely as it should back through the cable outer housing, i.e. in the picture above, it doesn't slide from left to right very well. I'm wondering if I'd be better off not using the cable guide attached to the seat post clamp, and just run the cable straight past the seat post, for a less curved setup. Comments, anyone?

 

[Shut Up Legs]

I think I may need to replace both brake cables, and their outer housings . They're both failing to pull the brake pads away from the wheel upon releasing the levers. I'm still interested in people's opinions of how best to route the rear outer housing around the seat post, though .

 

[RWright]

I just looked at my (road) bikes. The brake cables are not set up like those. The cable pretty much runs along the frame, below the top of the seat tube and the brake cables are connected on one side side. Ulegra and 105 Brakes are what I have. Sorry I am not much help.

 

[Shut Up Legs]

I just looked at my (road) bikes. The brake cables are not set up like those. The cable pretty much runs along the frame, below the top of the seat tube and the brake cables are connected on one side side. Ulegra and 105 Brakes are what I have. Sorry I am not much help.

Thanks for the reply, anyway . I was thinking of arranging my cable outer the same way, to reduce the bend.

 

[Brandane]

Looks like the outer is too long and needs cut a bit shorter; but strange that it worked fine before pad change?
Don't by-pass the clamp at the seat post unless you are going to run a longer outer all the way to the barrel adjuster on the caliper otherwise your brake isn't going to work at all.

OR ... Will running the cable round the other side of the seatpost give it a slightly longer run (looking at where that cable guide is on the crossbar). At the risk of stating the obvious, to do this the easy way pull out the seatpost and move the cable rather than disconnecting the cable!

OR .... Maybe the inner or outer (or both) are corroded in there and need replaced.

 

[Mo1959]

I nearly had a blonde moment and said water is maybe running in due to the angle then noticed the bike was upside down.

 

[Brandane]

I nearly had a blonde moment and said water is maybe running in due to the angle then noticed the bike was upside down.

Of course it is, Victor is in Australia!

 

[Mo1959]

Of course it is, Victor is in Australia!

 

[raleighnut]

Ditto for shortening that length of outer and possibly increase the tension on the brake arm return springs.

 

[Shut Up Legs]

Looks like the outer is too long and needs cut a bit shorter; but strange that it worked fine before pad change?
Don't by-pass the clamp at the seat post unless you are going to run a longer outer all the way to the barrel adjuster on the caliper otherwise your brake isn't going to work at all.

OR ... Will running the cable round the other side of the seatpost give it a slightly longer run (looking at where that cable guide is on the crossbar). At the risk of stating the obvious, to do this the easy way pull out the seatpost and move the cable rather than disconnecting the cable!

OR .... Maybe the inner or outer (or both) are corroded in there and need replaced.

Actually, it didn't work that well before the pad change. It's been slowly getting worse over the last few months.
As for the "easy" option of removing the seat post to reroute the cable: it's not going to happen! My seat post has been firmly stuck for a few years now, and it's not going anywhere. One of these years, I may get around to trying one of the hardcore seat post removal methods, e.g. hacksaw, nasty chemicals, etc., but for now, it's staying put.

I think I'll replace the cables and their outers, because it's been a while since the last replacement, anyway. I'll take this opportunity to use a shorter outer cable at the rear, and also increase the brake arms' spring tension.

Thanks for the replies, people: I appreciate it. CC comes up with the goods, as usual!

 

[Shut Up Legs]

Another question: what the hell is the bit of metal, with a notch in it, that sticks out from clamp on the right hand side (at the vertical centre) of the image below? I have brakes just like these, and never know quite where to put that metal bit. Should it be as close as possible to the cable guide, or point upwards?

 

[Shut Up Legs]

I've just replaced both brake cables, and the routing of the front cable outers along the handlebars is my best one yet, with minimal bending . Below shows my first attempt at routing the rear cable outer past the seat post:

I have to leave about 1cm between the bottom end of the cable outer, and the cantilever brake pivot, because when I pull the brake lever, the cable outer moves towards the pivot. I'll also have to make the cable outer fit fairly tightly into the cable guide on the top tube, so it doesn't remove itself after repeated braking. Comments, anyone? I'm in no hurry to get this bike ready for tomorrow's commute, because I want to get the brakes just right, so I think I'll use the road bike to commute this week.

 

[morrisman]

I've just replaced both brake cables, and the routing of the front cable outers along the handlebars is my best one yet, with minimal bending . Below shows my first attempt at routing the rear cable outer past the seat post:

I have to leave about 1cm between the bottom end of the cable outer, and the cantilever brake pivot, because when I pull the brake lever, the cable outer moves towards the pivot. I'll also have to make the cable outer fit fairly tightly into the cable guide on the top tube, so it doesn't remove itself after repeated braking. Comments, anyone? I'm in no hurry to get this bike ready for tomorrow's commute, because I want to get the brakes just right, so I think I'll use the road bike to commute this week.

I am surprised that the brakes work at all with this set up. Unless the outer is firmly clamped/held at both ends it will not function as designed. You need to route the outer via the seat post clamp to enable the brakes to work correctly.

 

[Shut Up Legs]

I am surprised that the brakes work at all with this set up. Unless the outer is firmly clamped/held at both ends it will not function as designed. You need to route the outer via the seat post clamp to enable the brakes to work correctly.

I'm aware that's the usual setup, but it was causing problems, because I couldn't find a way to route the cable without it bending too much. There has to be a better way, surely?

 

[raleighnut]

Those brakes need to pull bare cable from the fitting on the seatpost clamp to where the wire splits in 2 easiest fix bin em and fit a V-brake, they use the same pivot blocks on the frame and covered cable from the top-tube fitting. Cost here 19.99 for Deore but there are cheaper versions plus you can do away with the fitting on the seatpost clamp, you may need a longer piece of outer cable but that's a couple of quid a metre here so should be all do-able for $40 Aus