Tech Question: Handlebar Bag vs. Hydraulic Brakes

Phoo

Observer
Good morning bike people,
I'm currently neck deep in a big dumb road trip, and generally riding my face off at all reasonable opportunities. The idea has been bouncing around in my head that I should make a point of doing a few overnight (or even multi-day) trips on the bike before I put things in park. In my quest to hack together some kind of budget setup, I'm looking for ways to lash a few items on my handlebar. It appears from photos that most folks have artfully routed their mechanical brake cables away and around their bags/rolls.
The question:
For those running hydros, has anyone experienced line failure (particularly where the hose meets the master cylinder) from bag chaffing or vibration? Any innovative solutions aside from completely redoing my brakes? Any sort of bag or roll would likely end up sitting atop the levers and hoses.

Thanks and please forgive my ignorance if this has been previously addressed (I looked!).

-Phoo
 

Christophe Noel

Expedition Leader
Most people who just toss something together and lash it to their bars eventually have trouble with their lines. It's one reason why I try not to run a bar bag unless forced to. I also really dislike the weight and clutter up front.

Some people run longer lines (me) with the hope of those lines running outside or around the bag. Others squash the lines under the bag against the bars, which can isolate them from movement, but can also crimp and damage them if not done well. I think once you start futzing with your bar bag setup, you'll figure out what solution causes the least disruption to your lines.

But yes, if done carelessly, it will cause a problem, and not just to brake lines, but shift housings as well.
 

DaveInDenver

Expedition Leader
I run my rear brake line behind the bag, it ducks under between the stem and bag and snakes around the head tube and under the top tube. I encase my brake line forward of the stem to the first braze-on with a outer jacket of 3/16" vinyl to prevent chaffing and cutting. My stem is a Thomson Elite X4, so the stem face plate has relief cut into it and the edges aren't *super* sharp.

I run XT hydraulics, BTW.

My front is long enough to route with a lazy loop in front of the bag.

I would run them both long enough to route in front but I had already trimmed my rear a bit too much to do this. I also kind of think super long loops appear sloppy if you don't have a bag on, so I trim them. I also swap the side the rear hose routes around the head tube, to the left side normally and on the right to gain a bit of extra slack with a bag installed.

I've found this works fine for me using an older Sweetroll with just a couple of foam spacers on the mount, which I guess would equate to a medium size one now. I used to route both hoses behind the back but did rub the fork crown with the front one being trapped between the fork and bag. I run FOX forks so there's quite a lot of movement between the front wheel and bars, though.

My main concern is finding a lever angle that doesn't force the hose to take too drastic of a bend coming out. You have to run the bag fully dropped, almost straight down from the bars and it can't be a super round dry bag, maybe 7" at most, with a reasonably long stem (mine's 100mm). A stubby DH wouldn't work for my routing. My bar bag is where my sleeping bag/quilt and clothes go, so I try to keep the weight low in front.

I don't have shifters, so no help with shifter cable routing.
 
Last edited:

Phoo

Observer
Thank you both for the comments. I did try some preliminary futzing before I left home, and all solutions looked fairly undesirable. Unfortunately, I did a rather tidy job of routing hoses and cables on this particular bike, which is now my current undoing! I was hoping to stash the bivvy sack or sleeping pad there, but they may have to go elsewhere. Will snap a photo once I get my junk together and rolling down the trail.

And Dave, good on ya for riding 1x1 in a mountain state. Not sure I've got the moxie for that kind of punishment.
 

Christophe Noel

Expedition Leader
I think this has as much to do with the bag as it does the lines. I just received some new Topeak bags to try. They're quite affordable, and the bar bag appears to be designed well enough to escape a few brake line woes. As Dave said, the angle of the lever might need to be tweaked as well, if not to reduce interference with the lines on the bag, with the lever itself.

As for his 1x1, I did thousands of miles of bikepacking on a singlespeed, including a few hundred mile rides on the Colorado Trail. It's all about the right gear, and the right kind of walking shoe. :)
 

DaveInDenver

Expedition Leader
That photo is segment 15 at the bottom of Fooses Creek just up from CR225 on the CT a little more than a week ago now. I used Shimano XM700 shoes for the CT and I walk a whole lot. I only have the REEB, that's all I ride. Did Durango to Moab last September, Rollins Pass in October and a few races here and there (12 Hours of Mesa Verde, 40 In The Fort) in the last year. I don't think there's ever a right gear but then again you're also never in the wrong one, either.
 

Phoo

Observer
That is quite slick. I was contemplating some way to use old-style bar ends as a bag rest of sorts, but of course, this is a bit more elegant. Currently trucking across CO, and aim to get out for a quick 1 nighter soon. Will see if I can make it without a bar bag for the first run.
 

that-guy

New member
I wouldn't worry about it too much. I've never seen or even heard of a hydro line chaffing to the point of failure. It would take thousands of miles at a minimum.
 

Phoo

Observer
To follow up with all things:
Overall, I'm a bit more worried about fatigue than chaffing for the brake lines. From my recollection at time of installation, the weak point on a Shimano setup is the little brass crush-fitting that holds the line firmly in place on the master cylinder. It's all just speculation at this point, but I'm imagining that some number of vibratory and/or impact cycles would cause that part to deform, loosen, or otherwise let go in such a way that a leak starts. This whole setup is still a work in progress, so we shall see.

Anyhow, I now have two, short overnight trips under my belt. The first was an out and back on the Colorado Trail between the CR. 6 trailhead near Breckenridge and Georgia Pass. The second was the first segment of the Kokopelli Trail, from the start out to Rabbit Valley. First, a couple of photos:





I'm using an Ortlieb saddle pack and a Salsa top tube bag as my store bought pieces of gear. The bivy sack is stuffed and lashed into the main triangle, and my thermorest is lashed to the top of the handlebars, resting against the stem. I thought of using some "Voile straps" for this purpose, but they were out of budget, so I made some straps out of an old inner tube and some replacement side-squeeze clips (~$3 at REI). I'm out about $200 for gear at this point. Not too shabby. The rest of my gear is in my 22L day pack.

I'm currently limited on food and water storage until I figure out how to either get more stuff on my handlebar or into the main triangle of the bike. The back pack is more or less maxed out, and I don't want much more weight on my back anyhow.

Aside from nearly catching fire in the August heat on the Kokopelli, the only real "incident" of note was when my saddle pack got sucked into my rear wheel when I popped off a little roller while descending on the CT. The main bag was okay, but there is a small hole where it pinched at the seatpost interface. The lesson here is to be mindful of packing, compression and resulting bag-sag!

Good experiences overall, and this is turning out to be a great way to explore some trail systems as a wandering cyclist. I'll probably wait until I get to some more favorable climates before I set off on my next mission.

Thanks for all of the inputs!
 

Hnoroian

Observer
I agree with that-guy, but there are also handlebar accessories mount similar to something like this that would move it further away so you can mount your hoses behind them.
image.jpeg
 

Christophe Noel

Expedition Leader
I wouldn't worry about it too much. I've never seen or even heard of a hydro line chaffing to the point of failure. It would take thousands of miles at a minimum.
It's not the chaffing. It's pressure at the juncture of the line and the brake lever itself. That's where most lines and housings fail. And it does happen, you bet.
 

Hnoroian

Observer
Another thought also is that if one is that far out in traveling wouldn't you carry a spare section of hose and a small amount of fluid anyways?
 

DaveInDenver

Expedition Leader
Another thought also is that if one is that far out in traveling wouldn't you carry a spare section of hose and a small amount of fluid anyways?
You could do but if you have a blow out it would be a tough fix without a way to bleed them. The hose isn't super packable, carrying fluid, the tools, so it's not really ideal. Brake-wise I carry extra pads and would make a plan to get to a bike shop otherwise.

The better way to deal with remote brake issues is to run mechanical ones. My feeling is the better braking and reasonably low chance of issue is worth the potential pain of hydraulics but if I was touring places that weren't a day or two limp to a hitch hike or town that might be a different conclusion.
 
Top