Derailer cable tension issue

[raleighnut]

It was still very hard to shift gears with the cable in the position shown in the above photos. Running the cable on the inside of the little 'nub' was virtually impossible as it just pulls out.

I put the cable above the 'nub' (see photo below) and now it works delightfully . No more stupidly high tightness, and I no longer have to put up with a frayed cable.

View attachment 446403

That's where the cable should go, if you had it on the other side no wonder it was stiff

 

[mickle]

It was still very hard to shift gears with the cable in the position shown in the above photos. Running the cable on the inside of the little 'nub' was virtually impossible as it just pulls out.

I put the cable above the 'nub' (see photo below) and now it works delightfully . No more stupidly high tightness, and I no longer have to put up with a frayed cable.

View attachment 446403

I was gonna say. There's your problem.

 

[Ajax Bay]

I would run the cable so it is inside the flange all the way, not cutting over the top of it.

you've managed to avoid over-tightening and crushing it, a common mistake.

I put the cable above the 'nub' (see photo below) and now it works delightfully .

Steve - apologies for my poor description. I was trying to suggest that the cable should not go 'over' the flange/nub (your earlier image). The clamping route you've shared is just right (and I have just replaced my FD, clamping the cable in similar fashion). I note that you have it tight and the cable is suitably crushed. How one can tighten the clamp bolt adequately and not 'crush' the cable is a conundrum which only a special few can solve.

 

[Globalti]

It's simple, you just need a mechanic's "feel" for when the bolt is tight enough without crushing and splaying the cable. This means having a feel for the elasticity of materials.

 

[Ajax Bay]

you just need a mechanic's "feel"

Go and 'feel' / look at your cables. Is the smaller diameter of the cable less (than a normally round cable) where it's secured? If so it's crushed (a bit). If not I suggest it is not securely clamped (aka "tight enough").

 

[DCBassman]

How do you know when it's tight enough? When it's tight enough!

Agreed, there is a feel about it, mainly knowing when you're trying too hard.

 

[steve30]

If its too tight, it will break. If its not tight enough, it will fall out easily .

Evidently, the way I have the cable now *is* correct, as it works nicely. Last time I changed the cable I put it in [kinda] as shown in the earlier photo which is why it didn't work right, and it was so prone to coming off that I ended up tightening it up to the extent that some of the strands broke. Still, it lasted me well for two years until I got fed up of it recently.

I'm not sure how I didn't realise this at the time. It must have been done correctly before I changed it. But in the installation manual for the derailer, the diagrams make it look like my wrong way was actually the right way.

 

[roadrash]

alls well that ends well