Are the brake hoses on your road bike too long?

Because I opted for Shimano’s J-kit hydraulic brake caliper and STI lever bundle, on mine, they definitely were.

All that brake hose flapping about…not very clean looking.

That’s the price I paid for a convenient install, which is invaluable for the bike assembling factory folks the J-kit bundle is meant for. Assembly time saved means more bikes out the door available for sale.

As Hyro is my bike, however, I decided to do something about the excess hose length. You’ll need the following to proceed.

A bag of brass brake olives and BH59 end fittings for Shimano hydraulic brake lines. The BH59 fittings have a groove around the lip.

  • A set of relevant brake hose end fittings and olives. These are specific to your brake system. Most Shimano road bike hydraulic brakes use BH59 hoses, and those require BH59 end fittings. Shimano does not recommend using BH90 fittings on most road bike hydraulic brake systems.
  • A brake hose clamping block. Shimano calls theirs the TL-BH61, looking like two halves of a small pencil sharpener. It’s meant to hold brake hose in a vise or clamp without crushing it. It should come with the parts bag for your braking system; alternatively, some brake bleed kits will have an equivalent.
  • A bench vise. Alternatively you can use locking pliers such as Vise-Grips, like what I’ll be doing here, but a free, mobile vise is definitely the best tool for the job.
  • A small or medium hammer, or equivalent. One of the few bicycle mechanic jobs where a hammer is actually needed.
  • An 8 mm open wrench or adjustable wrench.
  • A sharp knife.
  • A plastic bag and rubber band you can use to wrap your front brake caliper with, to avoid mineral oil spillage.
  • A rag or paper towel.

This method will shorten the hose at the STI lever. Start by undoing the bar tape, cutting any sticky tape holding the brake hose in place, and peeling back the brake hood on the back end to expose the hose nut.

Take your 8 mm wrench and undo the hose nut. Once loose, slide it down the brake hose. We will need it again later.

Note how different this olive looks from a fresh unused one. It looks like a microscopic beer keg.

At this point there is no longer anything holding the brake hose in place except for the friction in its present olive. Pull on the brake hose to break the olive free from the STI lever body. Watch out for leaks.

The brake hose is now free. As with brake cable housing, you can now measure to size it down accordingly. As this is a front brake hose, the only real sizing consideration is it should be long enough to reach the STI lever with not too much slack. One of the best practices is to take into account the movement of the handlebar into resizing the brake hose, though, making sure it can be turned all the way to both sides without binding.

In Hyro’s case, everything past my thumb is slack brake hose. That’s a lot of slack. Be very sure about the sizing: “measure twice, cut once” as some people say.

Once committed to a hose length, break out your knife and cut the hose as perpendicular as you can get it. I have a rag underneath to catch the mineral oil that will leak out.

After cutting, sandwich the hose into the brake hose clamping block.

Take one of the brake hose end fittings and push it into the inner lining of the brake hose to get it started. Hammer it down all the way in afterward.

You want the brake hose end fitting’s lip to be as flush with the brake hose’s inner lining as possible. Once done, you can release the hose from the clamping block.

Thread a new brass olive onto the brake hose, then push it into the STI lever body. Keep inserting pressure on the brake hose as you move the olive and hose nut into position for reattachment.

Once the threads on the hose nut catch onto the STI lever body, tighten it down with the 8 mm wrench. This will effectively crush the new brass olive, deforming it into a shape that will seal the brake hose end. Tighten the hose nut to 7-8 Nm of torque, which is quite a bit of hand force, but nothing too crazy.

That’s job done; the nice thing about this is you’re likely going to do it just once per bike, unless the hoses themselves get damaged. Return the brake hoods into place. You’ll want to check the brake lever action; pull on the lever and see if it feels spongy or has too much travel before biting. If all went well, the brake lever should feel exactly the same as before; if not, you may have lost too much mineral oil while the hose was disconnected. That will call for a bleed job – the main periodic maintenance job for hydraulic disc brakes – which I’ll cover next time.

And just in case you wanted to see how Hyro’s brake hoses looked post-surgery, here they are.

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The early adopter dilemma, part 3: “This one goes to 11”

Previously I wrote about the history of disc brakes on road bikes, and how Hyro was a technological dead end born from their introduction. Given all that, I went ahead and turned Hyro into the most versatile bike he could be.

All these parts will go onto Hyro.

A last look at my Shimano FD-5700-F front mech. This was the last 105 unit that didn’t have the groupset logo engraved into the cage; it was on a sticker that had come off a long time ago.

These TRP Spyres have served me well.

Hyro shorn of his drivetrain and braking hardware.

Doing that involves stripping almost everything out: the TRP Spyre mechanical disc brake calipers, the Shimano 105 5700 drivetrain parts, the STI levers, and the Jagwire compressionless brake cable housings. The only things left were the Shimano 105 FC-5750 crank and the bottom bracket it spun in. Despite the deep gouges and scars, it had fresh chainrings.

The Shimano CS-HG700-11 cassette broken down into component pieces. All but the largest three cogs are individual.

I previously remarked that Shimano’s CS-HG700-11 cassette was the only way to preserve my current wheels, and that turned out to be true. It fit onto my 10-speed freehub with no drama at all. Off to a good start, then.

Next, the ST-RS685 STI levers and BR-RS785 brake calipers went on. I did the front one first, since it was a more straightforward external routing job for the front brake hose. Giant gave this TCX frame a cable guide that bolts onto the underside of the fork crown to hold brake housing or brake hose in place. In the end, it worked, although I’m convinced the brake hose is about 5 cm too long.

This bolt-on front brake cable/hose guide lives underneath Hyro’s fork crown.

The hydraulic brake J-kit’s pre-installed front brake hose is a little too long. Ideally that lower run should hew closer to the left fork leg.

Photo taken from the other side. All that excess brake hose will flap in the wind. As this is an external run, this should be easy enough to shorten.

Hooking up the 105 FD-5801 front derailleur was my next job…and this was pretty confounding. Because the FD-5801 now sports onboard cable tension adjustment, I could dispose of the inline barrel adjuster, but the way you cable these new cam-actuated front derailleurs is just so strange. The shift cable is pinched by a plate that is held on by a bolt, as before. However, the pinch plate itself is pushed by the cable tension adjuster grub screw as you turn it in to adjust. All this time, the end of the gear cable is supposed to go around the top of the derailleur. A lot of head-scratching occurred here, and it doesn’t help that peeling the ST-RS685 brake hoods to expose the cable exit port also blocks the action of the shift levers, leading you to think that there’s something wrong with them.

Despite the older model name and groupset logos, this Shimano 105 FD-5801-F front derailleur is identical to the newer FD-R7000-F unit.

Mounting this thing and setting its cable tension is a very different ball game from Shimano’s older front derailleurs. Follow the instructions!

Next was the rear brake caliper. This is where the split nature of Shimano’s J-kit OEM brake package was very helpful, especially since the TCX frame has pretty fancy/irritating internal cable routing. Since the rear caliper wasn’t yet hooked up to a brake lever, it was much easier to route the hydraulic brake hose through the holes of the frame. As before, Park Tool’s IR-1 internal routing tool was a godsend, literally pulling the brake line through the frame with the guide cables and guide magnet. Shimano BH59 brake hose is also much more flexible than Jagwire KEB-SL compressionless brake cable housing.

Unlike in this photo, I had to route the brake hose in the opposite direction: from the chainstay, through the frame, and up to the STI lever. In both cases, Park Tool’s IR-1/IR-1.2 cable routing tool makes the job much easier.

Making the right ST-RS685 STI lever talk to the 105 RD-R7000-GS rear derailleur was the next major challenge. As with the front derailleur, cabling this thing was also pretty strange, mainly because of how the shift cable exits the TCX’s rear chainstay and where the cable entry port now sits on the RD-R7000. This required a rather tightly bent section of shift cable housing: generally not recommended, but here it’s almost a requirement. When you do cable it up, the excess cable run is hidden underneath the RD-R7000’s linkages, so it ends up hitting your spokes as you do your indexing and test shifts…until you finally cut the excess cable and bend it out of the way. Older derailleurs also had a more finger-friendly barrel adjuster for cable tension adjustment, too.

Left uncut, as usually done on installation and cable replacement, the RD-R7000’s shift cable is guaranteed to run foul of the rear wheel’s spokes. Very strange decision by Shimano here.

This barrel adjuster is quite a step backward vs. older rear derailleurs. It’s much harder to turn, as your fingers have less purchase on what little knurling it has.

This tight twisted loop was the best way I could think of to run the shift cable between the RD-R7000 and the TCX’s chainstay-mounted shift cable port. Fortunately, it works.

Finally we have the J-kit connection of the rear brake caliper to the right STI lever. At the caliper end, you take off the rounded black cap, which exposes a cleanly cut brake hose with a seal on it. At the STI lever end, you twist and pull off the yellow plug…and this reveals a hose nut socket at the end. Plug the two together and tighten the hose nut against the J-kit connector with wrenches, while dealing with the slow trickle of mineral oil. If all goes well, you should get a good connection with no leaks and no need for bleeding…which was what I got. Hurrah!

The round black cap on the foreground is part of the brake hose, as routed from the brake caliper through the frame. The yellow cap on the background is from the STI lever.

Removing the black cap reveals this white seal. Removing the hexagonal yellow plug reveals a modified Shimano 8 mm brake hose nut, where the end with the white seal seats into.

Here’s the finished J-kit “easy hose joint” rear brake connection. Note the wrench flats which I’ve conveniently scuffed up.

Even with some exposed threads on the hose nut, this worked out very well and I have had zero leaks after installation.

That should have been the end of it, but I found terrible brake rotor rub at both ends while centering the calipers. I ended up having to take out the wheels and brake pads, and pushing back the pistons on the BR-RS785s with tire levers to reset them to their starting positions. Pads and wheels reinstalled, I repeated the caliper centering and it now worked well.

You could imagine my excitement to ride Hyro after this lengthy upgrade job. Unfortunately I succumbed to sickness shortly afterward. Riding impressions will have to wait until next time.

The early adopter dilemma, part 2: What next for Hyro?

In the previous installment, I went over a bit of history and discussed how we got to this point, where drop-handlebar bikes gradually moved from no disc brakes at all, to mass-market adoption.

As with many of his contemporary bikes, Hyro has open dropouts; 100 mm front hub spacing and 135 mm rear hub spacing; and post-mount hardpoints. This leaves him in a funny little limbo in that it limits his possible upgrade paths.

Let’s start with the hubs first. Unlike everything else here, their interface with the bike is non-negotiable. There is no way to fit through-axle hubs on a bike with open vertical dropouts. That said, perhaps it’s testament to Giant’s construction methods that I’ve never had any problems with frame and hub rigidity, nor its symptom of brake rotor rub, over the last five years…despite running quick-release hubs. Besides, many 135 mm/100 mm QR-axle hub options still exist, and they’re not going away anytime soon.

While TRP’s Spyres are great mechanical disc brakes, they cannot overcome the inherent weaknesses of the brake cable: you still need quite a bit of hand force to get the brake calipers to actuate, especially from the hoods. The calipers themselves have rather stiff return springs, which can be potentially fatiguing on longer rides with lots of braking. Riding around the Philippines, where anyone and anything can become a sudden obstacle, any brake force multiplication you can get is welcome, in my opinion.

Four years on, with lots of kilometers logged, Hyro’s Shimano 105 5700 drivetrain is still strong, but aging. Shifting to the big chainring, even with fresh ones mounted, yields intermittent sticking in the left STI lever, although it improved after dripping some Boeshield T-9 into the mechanism. Also, having enjoyed Shimano’s new brake hood shape and profile after riding a Lynskey ProCross equipped with Tiagra 4700, I realized that the 105 5700 hoods are just a tad too bulky and wide for my hands.

With all this considered, I might as well go big and upgrade to a modern 11-speed groupset with hydraulic braking. That goal was on my mind for a number of years, but the cost had been prohibitive…until now.

The bulk of the expense of a groupset is in the STI levers. With hydraulic disc brakes, the brake calipers have to be sold in a set with the STI levers because the latter contain the master cylinders, which jacks up the cost even more.

Now that the road cycling world has largely moved to Flat Mount for its disc brake needs, I got a good deal on the ST-RS685 + BR-RS785 combo. Shimano calls this the “J-kit” version, meant for original equipment manufacturers.

A J-kit hydraulic brake system is pre-bled, and already has the barbs and olives hooked up to the critical end points. For the rear brake, all you need to do is affix the STI lever and brake caliper to where they should go, route the brake hose through the frame (if needed), and then link up the two hoses via this in-line connection exclusive to J-kit systems.

Done correctly, assembling a J-kit system into a bike should require no bleeding at all. Building this up should be interesting.

The BR-RS785 caliper is essentially a Deore XT BR-M785 unit for mountain bikes, remade for road use. The main difference is the banjo fitting gets swapped for an in-line brake hose connection. In case these BR-RS785s give up the ghost, it should be easy enough to replace them with any Shimano mountain bike unit.

The J02A finned resin brake pads boast half of Shimano’s IceTech technology. The idea is to help dissipate heat and combat brake fade under prolonged braking by radiating it to the atmosphere via fins and better materials. A metallic-compound J04C version of this pad is available, and these can be swapped with non-finned G02A or G03S pads if needed.

The ST-RS685 STI levers predated Shimano’s introduction of hydraulic braking into its road bike groupsets. The nomenclature does quietly indicate that they are Ultegra-level parts of the 6800 generation, meaning this is a 2×11-speed STI lever set.

Cosmetically, they look very similar to Ultegra ST-6800 levers, save for a taller profile and a touch longer reach. This was Shimano’s first attempt integrating a brake master cylinder and mechanical shifting into the brake hood. Steve Tan of “Hands on Bike” took a deep dive into the ST-RS685, and noted how the hydraulic piping is built into the aluminum bracket, lending even more of a “prototype” feel. When Shimano finally baked hydraulic braking into the Dura-Ace R9100 groupset, it returned to lightweight resin for the brackets.

The ST-RS685 has this white stopper wedge installed on the right lever as packaged. When in place, this prevents both shifting and braking actions, thus keeping the seal on the J-kit sleeve connector intact before the hydraulic lines are mated.

This angry, angular looking thing is a Shimano 105 RD-R7000-GS rear derailleur. Shimano yaks about the Shadow technology offering better protection in a crash, but it doesn’t tell you that rear derailleurs of this ilk have a much stronger P-knuckle spring, increasing chain tension and reducing chain slap. This is the real step up from the older Ultegra RD-6800 and 105 RD-5800 units, and there should be no problems mating this with the ST-RS685. It’s officially rated to handle a 34T biggest cog.

Photo credit: Shimano Europe.

Also borrowed from mountain bike tech is the cassette. The CS-HG700-11 unit sports an 11-34T range. Since Shimano didn’t resort to the 1.85 mm freehub body extension on mountain bikes, this particular 11-speed cassette will fit on a 10-speed freehub body, because the 34T cog is large enough to be dished over the spokes. No other 105-level 11-speed cassette has this kind of backwards compatibility, and this will allow me to keep using my current Giant S-X2 wheelset for a little longer. Its gear jumps are relatively big, though, with many cogs in two-tooth increments.

The CS-HG700-11 cassette comes with its own 1.85 mm freehub spacer for compatibility with 11-speed road bike freehubs. On a 8/9/10-speed freehub, you won’t need it.

Last on the drivetrain upgrade parts list is the Shimano 105 FD-R7000-F front derailleur for braze-on mounting. This contains the cam-actuated mechanism on Dura-Ace R9100 and Ultegra R8000, but was actually first seen on the 105-level FD-5801 unit, which was a mid-life update of the original long-armed front mech. These new front derailleurs now come with onboard cable tension adjustment, negating the need for an in-line barrel adjuster.

A number of friends have suggested replacing the 2014 TCX frame with something more modern. I don’t see why I should. Sure, it’s a dead end, but it’s not hopeless, and this is a good opportunity to push Hyro’s potential to the limits of his design.

I will be documenting the build process here. Watch this space.