Yoeleo R11 new project

[Mr.Gib]

I've posted this a few times but again, juin brakes work perfectly with internal routed cables and rim brakes shifters.
They may be a little more sensitive to cable length but it's only when you try and shove a few extra inches of cable into the frame without trimming them correctly.
So such speculation on this subject from people who haven't actually tried it.

Not quite.

While many frames work great with cable actuated disc brakes, some will be a no go. It comes down to how tight the bends in the cable housing must be. In some cases the required bends are so tight that it can be impossible to route the housing. It is possible to use a flexible brake housing, but performance is likely to be comprimised. I won't build with anything softer than Jagwire Pro housing - pretty stiff stuff. Yokozuna housing is even stiffer and might perform better but that stuff is a bastard to work with.

There are three areas of concern: the two cable exit ports for the calipers, and the location of the cable port in the headtube. For the caliper exit ports, a distance of 20 cm between the exit port and the dropout works well. As the distance approaches 15cm, things get tighter. At or below 15cm is not good. Even with the bendy segments that come with Jagwire Pro housing, cable drag increases to the point that the calipers may not open fully, and lever feel is likely to be stiffer and less repsonsive. Also be aware that whether a rear brake cable exits from the bottom of the chainstay or the inside can make a huge difference in terms of being able it to get it to the caliper cable stop.

As for headtube area, depending on the design of the headtube, downtube, and junction between the two, and the location of the cable port in headtube, a very tight S bend may be required. I have a Factor O2, with partially integrated cable routing, and while I have seen a photo of one built with Juin Tech brakes, it cannot be done with cable housing as stiff as Jaqwire. The housing comes up into the headtube from the downtube OK, but then has to make an abrupt 90 degree bend to exit quite close to the top of the head tube. Head tube cable entry ports directly in line with the downtube can alleviate this problem. Of course hydo hose is supple enough that this is less of a problem.

As for fully integrated, I imagine it would be an unusual fully integrated bar/frame combo that would be work well with cable actuated disc brakes.

FWIW, I have built or attempted to build five different frames with cable actualted discs, I am pretty good at it and know most of the tricks. Four were possible and one was not. I anticipate that most modern high end frames are a challenge with many an absolute no-go. Things can always be forced, but if they don't operate well, it's not a success IMO.

Perhaps the OP can give us a measure of the distance between the cable exit ports and the center of the dropout on the chainstay and fork. And where does the rear brake cable enter the frame?

[Steve Curtis]

Cable choice will make a huge difference. TRP compressionless cable and a surface ground inner like the Jagwire Elite Ultra-Slick will turn tightly with no problem.
Surface ground inners are smooth on the outside so are a tiny bit smaller diameter and are obviously smooth so allow tight turns.

As I've said, this works perfectly on the fully integrated bars and frame combinations I've built.

[Mr.Gib]

Thanks, I will have to give TRP compressionless a look.

Still, for a particularely tight build, I have used the bendy segments from Jagwire, which are certain to be more flexible than TRP compressionless, and found that the tight S bend from a chain stay exit to rear caliper hurt the lever action. That was with the polished inners. Interestingly this was with the original Juin Tech F1. On this particular frame, when I switched to the GT, with its improved cable stop location, it allowed another centimeter of housing which was all that was needed to relieved the excess friction.

Edit, just looked at the TRP cables. They come with the bendy bits also.