-
I was going to do this on the frame I’m building at the moment but with my limited equipment, I figured getting 3 bends in the stainless tube in the perfect place and at the perfect radius was going to be too much faff for me so I just put an exit a couple inches away from the BB for a tiny run of outer cable under the BB and then back in the chainstay
-
For my first Stayer (the green bike) the hose exits the down tube just before the BB on the side/top, then enters the chainstay on the top just after the BB (and out again on the top just before the caliper). So kind of like your solution but going above the BB instead of under. It's neat and I like it.
For my second Stayer (the sparkly bike) the hose exits the down tube just before the BB on the bottom/side and is then routed externally via one 'hook' (no zip-tie involved, not sure how it's called) put under the stay, under and on the inside of the chainstay to the caliper. So kind of like this solution but without the routing through the stay. It's also neat and I also like it. (The hose is black on sparkles so not really noticeable - and covered in mud most of the time. I should really take the rear caliper off anyway)
To me it seems the 2nd solution achieves much of the original intent (by going on the inside of the stay the hose is nicely hidden away, even if it isn't actually internally routed) with less faff than the first.
-
I have heard it is possible to do it through a T47 BB shell
It is, but it's hard with a 30mm bottom bracket spindle. However, if you're using a 24mm BB spindle it's a piece of cake, although as you say it'll depend on the BB you use.
I've been thinking about similar things myself recently as my next homebrewed bike will not have a T47 BB due to it using lugs, so internal routing just isn't an option. I can't really see the benefit of having an external tube rather than just running a short section of hydraulic hose outside the frame and underneath the BB. Strikes me it'd just make it a total bugger to clean, and to make. Also, your picture shows the extra tube being hard up against the junction between the BB, DT and CSs, so presumably that would reduce the area available for brazing the BB shell.
tl;dr - I'm with @PhilDAS - short stretch of hose externally under the BB.
You are reading a single comment by @Hulsroy and its replies.
Click here to read the full conversation.
PhilDAS
cgg
Brommers
@Hulsroy
I see soo many internal cable routing situations and issues that I have been scared to do it.
It does not appeal to me at all. The actual job of building a bike with internal cables have seemed dumb and tedious and it never really made me excited seeing it on finished builds either.
Back when is was into 80s road bikes it only caused me issues. But I have probably gotten myself into building a frame or two with internal hydraulic cable for the rear brake. Gears will be wireless and forks are carbon so I only have to do this one internal cable.
I have heard it is possible to do it through a T47 BB shell but that it doesn't work for all BBs. So I came up with running the stainless tube outside the underside of the BB shell.
I'd like the hive minds view on this:
2 Attachments