Damned internal routing. Best way to replace a rear brake hose?

[ishaw]

Fettling my son's bike today as it will get some use over the coming half term week.

Noticed the front brake had no pressure, so thought I'd bleed it but previous owner has rounded the bleed bolt on the lever. No problem, I was going to swap in some xt brakes anyway so that solves that brake.

However, the rear brake is internally routed and I didn't have the time to faff with that today so he's got odd brakes.

In preparation for when I get time to do the rear, What's the best way to do this.

I suspect from the front down as the hole to route it through is much smaller than by the BB.

I plan to tape the new hose to the old and pull through.

Would this be the right way to do it or am I best going from the bottom up?

Or is there a better way entirely?

 

[August Bicycles]

I usually do it with a short length of spoke, generally about 50mm of the centre section of a butted one.

Stick that in the end of the hose currently in the frame, then the other end in the new hose.

Try to push the old hose out with the new hose to avoid the old and new hose separating, you may have to gently pull the old hose whilst pushing the new hose through.

I don’t really worry about which direction I go from.

I’ve had to do this far too many times, this method has had good results for me.

Good luck!

 

[clubby]

The way to do it depends on your brake fittings. With ones where the hose is crimped to the fittings need done rear to front. Brakes with removable fittings at each end can be done either way. Also depends on the brakes you are removing. I’ve found with SRAM you need to pull through a spare hose with the old brakes and then fit the new hose the other way. I’ve a length of old hose for this task.

Also, treat yourself to one of these. Much more secure than taking hose together. Too much tape also makes it a ball ache to pull through tight spaces and small holes.
Much less likely to damage hose lining than using a spoke as well.


https://www.tweekscycles.com/rocksh...MIz5bduuHCkAMVTZVQBh2Pdi9WEAQYBSABEgLa9fD_BwE

 

[2manyoranges]

I usually do it with a short length of spoke, generally about 50mm of the centre section of a butted one.

Stick that in the end of the hose currently in the frame, then the other end in the new hose.

Try to push the old hose out with the new hose to avoid the old and new hose separating, you may have to gently pull the old hose whilst pushing the new hose through.

I don’t really worry about which direction I go from.

I’ve had to do this far too many times, this method has had good results for me.

Good luck!

Yep that's the way I do it - and have done it many times. You have to cut off the end section - about 2cms - which might have been damaged by the spoke but that's fine. And do it mainly by pushing hard on the hose going IN and very gently guiding out the hose which is coming OUT.

 

[ishaw]

I think I may have one of those barb connectors. Will have a rummage, thanks for reminding me that they existed.

It's for xt brakes if that makes a difference.

 

[old_coyote_pedaller]

You might have succeeded by now but I replaced the brakes on my Levo SL ebike with a new set of Srams so not XTs like yours. They came ready filled with brake fluid with end of hose to be fitted to lever having a bullet shaped end screwed on to the Sram Strealthamajig olive fitting. I still had to get it through frame from the rear but I had a length of 2mm dia glassfibre rod that had been used to shape one of those paper lampshades. I taped a piece of string to it and carefully pushed it through frame, took a bit of jiggling about though. The Sram bullet end piece had a hole through to tie the string to so was able to pull but also as someone said pushed as well, worked fine.
The barb connector clubby linked to also has a hole for a bit of string so same method could be used, hope you found yours.

 

[wynne]

I rivnutted external hose guides onto my last (and by last I really do mean THE LAST) internally-routed frame. Much the best long term solution for me. Probably absolutely no help to you, however.

 

[2manyoranges]

I rivnutted external hose guides onto my last (and by last I really do mean THE LAST) internally-routed frame. Much the best long term solution for me. Probably absolutely no help to you, however.

Yikes interesting and bold solution.

 

[wynne]

Interesting and bold, that's me.

 

[2manyoranges]

Ian you have best situation: hose already in. New one is therefore simpler/simple to instal as per instructions above.

Nice overview
https://escapecollective.com/threaded-14-an-easier-route-to-internal-cable-routing/

Not so if you have no hose already in.

Lots of awful experience of this.

Commencal 24 Supreme DH frame for Grom when small
No wire through raw frame, as per Commencal usual practice
Fine down to BB then awful routing into tight kink in chainstay
Time check - dark winter eve 6pm
wiggle
poke
jam
pull out
repeat
finally.....I can see it...grab it through hole with very fine grips
Time check 12 midnight. At least I had a break for supper.

Cannondale Badboy
Changing from cable to hydro
Pulll out cable outer since I read its an easy routing.
Big mistake.
What a way to waste a summer afternoon
In
jam
out
repeat
grrr
finally use 1mm wire to get through all the badly places holes then pull hose through with that

Transition Spire Medium Carbon complete frame rebuild after chainstay replacement
External brake
Internal gear
Grrrr
I see a difficult kink into chainstay
But...thank you thank you Transition
So easy
Poke poke suddenly appears at hole at rear, quick poke with a piece of wire and out it comes.
Hurrah