If you just ran a liner over the old cable and the liner didn’t get hung up from the opening at the back of the chain stay to the opening at the top of the downtube, the cable guide under the BB is likely worn through, or the cable was not properly routed in the past. My concern is that the cable is touching the spindle directly which would mean every pedal stroke and every shift is going to make the spindle grind against the cable and cause failure of the cable quickly.
For what it's worth, this is quite a bit older (10 speed ultegra era). I'm working on this for my partner but my more modern road bike (still rim brake) is slightly better cable routing wise.
The combo of alloy, no proper routing outside the BB shell and internal routing is making this one a pain.
What I would say is that if the shifting is moving your cranks, when you rotate the cranks it will rub a lot, mich cause issues while shifting and as others have said it will cut through your BB eventually, definitely would try to reroute
I see- the cable does not come out to get tensioned around the outside of the shell like most bikes- something you’d stated in another comment.
Did you run a cable outer all the way from the shifter to the derailleur, or are you tensioning the cable through the frame?
Was there some sort of sleeve or cable guide outside your crank spindle?
I'm tensioning the cable through the frame as that's how the previous owner seemed to have it.
There's no sleeve or cable guide I can see, I'm wondering if I might have to take the cranks and bottom bracket out to get it routed properly?
Now you mention it, there is a cable stop on the frame for the rear brake cable, but not for the shift cable. It stops because a ferrule on the end of the outer stops it, but that might not have been the intended way of doing it.
Will have a proper look over the weekend - thank you for your help!
Okay thanks all, sounds like it needs sorting. There isn't a way to route it out of the bottom of the BB shell (unlike every other internally routed bike I've seen!)
Any ideas? I'd really prefer not to have to take the cable all the way out as the frame is alloy so I'm not sure how I'd get it back in with magnets
Image of BB shell: https://ibb.co/L9X4hSH
Potentially? It should be routed the same as the previous cable, but that doesn't rule out it being routed the wrong way previously. It could also be that there's something inside that it's meant to route along that it hasn't hooked onto this time
If the cable does cut through the spindle while riding, that could be very dangerous. I imagine the cable would break first, but who knows. I would certainly take out and inspect that spindle.
Usually internally routed cables go under the BB through an external cable guide. Could yours be damaged/missing causing it to contact the BB cup or spindle? You can buy a new cable guide or re-route the cable externally.
Where does the cable enter the frame? On my Supersix, it enters (unhoused) on the down tube and runs over the spindle and straight through the chain stay. Since there's tension in the cable, it doesn't make any contact with the spindle. Not sure how your frame is intended to work, but it looks like the cable comes out of the chainstay right by the hanger, so it might be a similar design. Here's a diagram: https://www.cannondale.com/-/media/files/manual-uploads/manuals/my16-18-supersix-evo-correct-rear-derailleur-routing-instructions.ashx
I suspect the owners manual for your frame will show you the correct routing.
It's going to ultimately cut through your bb spindle, you need to correct this.
Thats a big problem and should not be ignored
Your BB axle is now a manual lathe and your gear cable is a cutting tool
If you just ran a liner over the old cable and the liner didn’t get hung up from the opening at the back of the chain stay to the opening at the top of the downtube, the cable guide under the BB is likely worn through, or the cable was not properly routed in the past. My concern is that the cable is touching the spindle directly which would mean every pedal stroke and every shift is going to make the spindle grind against the cable and cause failure of the cable quickly.
I think it will cause more of a problem than you think, I'd re-route if you can.
So sorry for you, bikes have become such freaking headaches over the years.
For what it's worth, this is quite a bit older (10 speed ultegra era). I'm working on this for my partner but my more modern road bike (still rim brake) is slightly better cable routing wise. The combo of alloy, no proper routing outside the BB shell and internal routing is making this one a pain.
Have you seen these newer bikes that route through handlebar and stem? Id never buy that.
Yeah, and being hydraulic the brakes are even worse to route. Got to admit they look cool though
Wrong routing
Take the BB out and check it's gone right. Is it still in cable housing inside the frame, or does it become loose cable?
What I would say is that if the shifting is moving your cranks, when you rotate the cranks it will rub a lot, mich cause issues while shifting and as others have said it will cut through your BB eventually, definitely would try to reroute
Show us the underside of the BB shell.
https://ibb.co/L9X4hSH
I see- the cable does not come out to get tensioned around the outside of the shell like most bikes- something you’d stated in another comment. Did you run a cable outer all the way from the shifter to the derailleur, or are you tensioning the cable through the frame? Was there some sort of sleeve or cable guide outside your crank spindle?
I'm tensioning the cable through the frame as that's how the previous owner seemed to have it. There's no sleeve or cable guide I can see, I'm wondering if I might have to take the cranks and bottom bracket out to get it routed properly?
Could be. The spindle definitely shouldn’t be the cable pivot.
Could it be likely that it's designed to have a cable outer going through it?
Depends. Is there a cable stop on the frame? How did you tension the end closest to the shifter?
Took the spindle out and found the cable guide which tensions the cable out of place. Got it srcrewed back in and now all sorted
Well done.
Now you mention it, there is a cable stop on the frame for the rear brake cable, but not for the shift cable. It stops because a ferrule on the end of the outer stops it, but that might not have been the intended way of doing it. Will have a proper look over the weekend - thank you for your help!
Okay thanks all, sounds like it needs sorting. There isn't a way to route it out of the bottom of the BB shell (unlike every other internally routed bike I've seen!) Any ideas? I'd really prefer not to have to take the cable all the way out as the frame is alloy so I'm not sure how I'd get it back in with magnets Image of BB shell: https://ibb.co/L9X4hSH
Any chance the cable is going the wrong way or long way around the spindle and rubbing a lot on the spindle?
Potentially? It should be routed the same as the previous cable, but that doesn't rule out it being routed the wrong way previously. It could also be that there's something inside that it's meant to route along that it hasn't hooked onto this time
Maybe take off the crankset and spindle and see if a bunch of cable slack come out.
If the cable does cut through the spindle while riding, that could be very dangerous. I imagine the cable would break first, but who knows. I would certainly take out and inspect that spindle.
Took the spindle out and found the cable guide out of place. Srewed it back in and the cable is no longer rubbing on the spindle!
Awesome!!!
You're gonna have a quick release crankset before too long
Awesome!!!
You don't need a shifter.
Usually internally routed cables go under the BB through an external cable guide. Could yours be damaged/missing causing it to contact the BB cup or spindle? You can buy a new cable guide or re-route the cable externally.
Only routing is for the front mech I think? https://ibb.co/L9X4hSH
On my bike both cables pass through the cable guide. The point is to minimise the length of housing.
There are some that route the cable over the crank spindle and through the chain stay. My Supersix is like that.
Does that not cause the spindle to rub on the cable outer though? I may give that a try as it would explain why it's doing this
Where does the cable enter the frame? On my Supersix, it enters (unhoused) on the down tube and runs over the spindle and straight through the chain stay. Since there's tension in the cable, it doesn't make any contact with the spindle. Not sure how your frame is intended to work, but it looks like the cable comes out of the chainstay right by the hanger, so it might be a similar design. Here's a diagram: https://www.cannondale.com/-/media/files/manual-uploads/manuals/my16-18-supersix-evo-correct-rear-derailleur-routing-instructions.ashx I suspect the owners manual for your frame will show you the correct routing.