'Over' bottom bracket cable routing

[Lots of steel bikes]

Hi everyone, I'm putting together my first 'over' bottom bracket build. The cable is touching the seat tube. Is that unusual? Shimano 600 FD. Cage in line with chain ring.

[Crittski]

I would not ride it like that, you will saw through the seat tube quick smart. I think that you should look at a low clamp derailleur instead. It will pull from a lower position on the seat tube and may create a cable angle of pull that doesn't cut your bike in half.

[GaryF]

I think the rear section of the cable guide may have been bent upward at some stage which results in the cable rubbing on the seat tube. I would investigate and perhaps it could be bent downward to its original position if that is the problem. It may need to be re-brazed in place which would require a paint touch up.

[munga]

I think the rear section of the cable guide may have been bent upward at some stage which results in the cable rubbing on the seat tube. I would investigate and perhaps it could be bent downward to its original position it that is the problem. It may need to be re-brazed in place which would require a paint touch up.

+1.

you can even see where it's lifted up (probably before the repaint).

[BRLVR.v2]

Yeah thats bent to buggery.





for reference

[rkelsen]

To get it running, I'd just run the cable under the BB shell. Use a nylon cable guide. They're found on hard rubbish. Otherwise, they can't be more than a few bucks at the shop.

Other options: Bend it back or use a short length of cable housing to protect your frame.

[Lots of steel bikes]

Hmmm, after seeing the guide on the orange frame I realize just how bent it is. I'll try giving it a careful bend. It looks very solid though. Thanks all.

[Lots of steel bikes]

I carefully bent the guide and now all is good. I didn't go too far just in case. There is now a couple of mm between the cable and the tube.
Took it for a run and didn't get far. It has a terrible case of auto shifting even under minimal pressure. Will investigate next weekend.
Apart from dropout adjuster screws, cable end crimps, nicer cranks and an Aliante saddle it's done. Here's a couple of pics. Odd sized unknown makers name frame with 61 ST 56 TT. Suits me just fine.
9 speed Ultegra shifters, brakes and rear D. Shim 600 front D. Suntour dropouts. Nice neat lugwork.