Gear cable snapping in sti shifter??

[Banjo]

I think normally just change the cable once a year would do. I hjad two go in quick succession then which was probably just bad luck but I was doing a lot of miles at that time.

 

[PatrickPending]

Only had this happen to me once....and I have no idea after how many tens of thousand km - generally I find when shifting goes a bit funny its time to change the cables. I've changed a couple where a strand has broken and avoided this situation.
The best bodge IMO would be to adjust the limit screws to keep the mech in the desired gear. I'd get rid of the broken cable...but hey it worked for you...

 

[HLaB]

I think its just the way the shifter works. It happened to me when a couple times when I lived in Scotland, more gear changes under pressure needed perhaps and muckier winters. Touch wood it never happened down south and I've switched to 2nd hand Ultegra anyway.

 

[Amanda P]

I've had a few gear cables snap. Mrs Uncle Phil had one break in the Campag shifter on her commuting bike the other day, and it broke about a centimetre away from the nipple inside the shifter. (She rode home in the high gear at the back and just used the front changer to give her 3 gears).

In my toolkit, I generally carry a spare gear cable. And I've had to fit one only only twice, I think, both times on tour.

When the cable's fraying and about to go, you'll notice it stretching, or peculiar gear-changing in the changes before it finally goes. That's the time to fix it - if you're in time before it goes.

 

[Globalti]

Cables snap when they get work-hardened by repeated bending in a very localised spot. A cable should pull straight from the nipple and any bending should be around a gentle radius. This is why cable nipples are sometimes held in a "swinging" anchor on a brake.

We had a lad on C2C whose mechanical disc brake pads were so worn that the operating lever had moved far enough that the cable was no longer lying on a radiused curve at the end of the lever but coming straight from the nipple, so that every time he braked the cable was flexing at the nipple. He couldn't understand why he kept snapping cables, in exactly the same place every time - they would gradually break, strand by strand as the steel work-hardened from repeated bending at a very sharp point.

 

[mrbikerboy73]

I have had two snap in less than a year, both times towards the end of 200 km rides. The cable has snapped by the nipple in the Shimano 105 shifter.

Bodged a get U home repair by locking the cable under a bottle screw bolt to hold it in a middle gear .

Had a cable almost snap on me at the shifter end after just under 4000 miles with my 105 shifters. I only knew as the gears wouldn't shift into a higher gear properly, this is on the rear. I appreciate this doesn't reflect how many shifts have been done in that time. The cables run underneath the bar tape so I don't think the increased angle at the lever helps matters. No doubt my own fault, I should change the cable more often. Love the get u home bodge, one to remember!