Touring - Surly LHT cable routing question

I recently got a Surly LHT factory built bike. The rear brake cable housing section that goes past the seat post seems to be too long to me, adding to the curvature.

I am wondering if this would be better with a shorter piece of cable housing.

http://i162.photobucket.com/albums/t244/mnhnhyouh/IMG_0195.jpg

z

Actually, that looks pretty good. You want a nice smooth line into the cable stops. I built up a LHT a couple of months ago and I may have made mine a little longer.

http://i783.photobucket.com/albums/yy112/Doug64_photos/DSC_0038-1-2.jpg

http://i783.photobucket.com/albums/yy112/Doug64_photos/DSC_0039-1-1.jpg

I recently got a Surly LHT factory built bike. The rear brake cable housing section that goes past the seat post seems to be too long to me, adding to the curvature.

I am wondering if this would be better with a shorter piece of cable housing.

AASHTA. Scroll down this page a bit: http://www.sheldonbrown.com/cables.html

So Sheldon Brown says this is correct:

http://www.sheldonbrown.com/images/cable-terry.medium.gif


but that this is wrong:

http://www.sheldonbrown.com/images/cable-terry.long.gif

and my pic looks much like the second one :(

SlowRoller, I dont know what AASHTA, please explain to an old man.

Doug64, yours looks like the cable bends one way, then the other, then back again, instead of being a smooth curve. It seems to me that your setup, like my current one, would increase the friction of the cable in the sheath.

z

too long. do as sheldon says:

http://www.sheldonbrown.com/images/cable-terry.medium.gif

Azesty, notice that in your example the cable runs on top of the top tube while the LHT makes it run under it. That makes all the difference. For the LHT the cable is less exposed to harm, less of a nuisance when you stand over your bike but it also means that a direct route to the brake would have to go around the seat stays and make sharper curves in the end. The S curve that they use is a compromise to run along the seat post, avoid the stay and come at a better angle to the brakes. IOW they use a longer route to avoid tight curves.

also, arent the brakes in the brakes in the sheldon brown pics side pull? wouldhn't that make a diff?

I think sidepull should require a looser cable, slightly, because it actually moves towards the wheel on actuation.

Here is a pic of Paul brakes guy's own bike with "loose" look housing:

http://www.paulcomp.com/paulsbikes/silver.html

You seem to be right, as far as I can see it. I use vbrakes which are pulled by the side and low also. This way my cable can drop in a gentle curve straight down to the brakes.

BTW, why does the S-curve on his new LHT bothers so much the OP? Azesty, are you experiencing braking problems which are related to this. I had a complete prior to my present build and never had a problem really.

Does your rear brake work? Is there a lot of force required to pull the lever? I'd guess that it works fine and you're sweating over minor details. If your cable is splayed by the binding bolt, or if the end is frayed you won't be able to get it back into the housing so you'll have to buy a new cable when you make the adjustment. If the cable can be put back in the housing I'd cut the housing down by a centimeter or so - until I got it to look like Sheldon's recommended picture. Otherwise I'd wait until I had occasion to replace the cable and I'd cut down the housing at that time.

Do you have a cable cutter? If not, I suggest you buy one. I cut bicycle cables with cable cutters from the hardware store for years and it always spread the ends of my cables so that I had trouble getting them through the housings. If I'd only known how much better a real bicycle cable cutter did the job, and how inexpensive they are, I would have bought one years earlier.

Also, when you cut cable housing you have to clean up the end or you'll add some friction to the cable. The housing has wire wrapping that tends to bend over the hole. I nibble away the bent part with my cable cutters, then file down the loose end, then ream the hole with a scratch awl, just to make sure nothings binding the cable. I don't know what the recommended procedure is, but this method works for me.

Be careful if you trim it, if you trim too much you might not have enough cable. Measure twice and cut once.

But, it is not a big deal if you do not trim it, that small amount of extra housing and slight increase in the bend of the cable won't add enough friction to be noticed.

have to feed the wire back thru the housing, will have to replace the ferrule and the crimp cap ,
and the end of the housing needs to be filed/ground flat, after cutting.

But it's OK as it is, not OCD perfect, But good enough.
I'd say leave it alone until your next maintenance cable replacement and do something different, then.

Although it will work, your cable housing is too long. You probably don't need to go to as flat as Sheldon's photo, but I would easily trim 1/4" at a time and repeat as needed. Purely aesthetic but shouts amateur :)

SlowRoller, I dont know what AASHTA, please explain to an old man.

Sorry, Azesty, too much slang. AASHTA = As Always, Sheldon Has The Answer.

In my opinion, your cable is a little long. I always shoot for as smooth an arc as possible. But if it works for you, it works for you :) You can always try shorter the next time you replace your cables. Good luck!

Yeah the back brakes work fine, though the supplied pads are not good. I have only done a few hundred km, and the back pads have worn down a fair bit.

Am about to go on a 450 km tour, starting Monday. I will leave the sheath as is for now, but replace all four pads with some Jagwire pads I have.

I dont have a cable cutter, but have just replaced all the cables and sheaths on my other bike. I just cut the sheaths with cutting pliers, and I have a small triangular file to open the hole out, and file the end flat. This seems to work very well.

Having done it recently means I have a fair bit of Jagwire sheathing left over.

When I cut cables I twist the individual strands back in place.

I am still working out if I want to keep the standard LHT build setup, or if I want to change the handlebars, shifters and brake handles. Will know more after a few more days in the saddle.

@SlowRoller, thanks for that, it is such a truism that it is almost tautological :)

z

Sheldon's picture is for side pulls and the cable routing is relatively straight. Not the same at all. Check out some of the reputable builders and see how they route their cables for canti's.

Sheldon's picture is for side pulls and the cable routing is relatively straight. Not the same at all. Check out some of the reputable builders and see how they route their cables for canti's.

You may be right. I see a lot of variation. On Bruce Gordon's site, I see some with shallow curves and some with steep curves:
http://www.bgcycles.com/Images05.09/RockNRoadLg.jpg
http://www.bgcycles.com/rnr_zoom2.html

Same with Bilenky:
http://www.bilenky.com/yellow_lugged_midlands.html
http://www.bilenky.com/sunset_red_midlands.html

These seem shallower...

Pereira:
http://www.pereiracycles.com/gallery/rando/pages/IMG_4429.php
http://www.pereiracycles.com/gallery/tonytour/pages/IMG_9849.php

Toei:
http://cyclofiend.com/cc/2010/cc771-bobrogen0410.html

It still looks a little long. But if your brake is working, don't fiddle with it.