As I mentioned in another recent thread I've just bought my first wrecked up 'classic' and am working on fixing it up. I've come to replacing the front derailleur gear cable as the old one was stretched, rusty, frayed and having no affect on changing chainrings.

I've got 2 problems I'd appreciate a few pointers on if possible, I've done some research but all the pics I pull up tend to be of newer setups:

1. I'm not sure if I'm setting everything up correctly when tensioning the cables. I'm currently putting the (downtube) lever right forward, parallel with the tube, with the chain on the smaller inside chainring. I'm then tightening the cable clamp on the derailleur with the cable pulled hand taught. So then when I pull the shift lever up towards me the cable should tension and the derailleur should be pulled outwards towards to larger chainring. Is this all correct so far?

2. The next problem is that when I put any tension on the cable, no amount of tightening of the clamp will stop the cable slipping. Comparing the pic below of my derailleur to similar ones online (see here), it looks to me the clamp is bent out of position. In a word, is my derailleur done for?! I can't get any leverage from the levers to pull the derailleur out towards the large ring, the cable just slips, is this likely to be the cause?



Thank you!

Might be bent, but it looks to me like you also have the cable too far off to the side, away from the bolt.

Yes, the setup you describe is correct. And yes, the derailleur arm is bent, try bending it back; also the cable should be clamped between the washer and the derailleur arm, closer to the nut as Lostarchitect said.

There are some OLD FDER's that are high normal. (pull cable to move to the small ring)

I had a SunTour on an early 70's 10 speed like that.

Thanks all for the advice, I will try and bend the arm back into the correct position. Although it looks to be pretty soft metal, think it may just snap off.

The reason the cable is so far over is because when you look closely at the washer (more like an l-shaped plate on this mech) there is a slight groove in it which I assumed was supposed to be to channel the cable into. Then the l-shape on the washer is presumably to help stop the cable slipping out the side. Admittedly though this setup doesn't seem very effective, maybe I'll just replace the plate with a regular flat washer and move the cable closer to the nut as suggested.

That clamp looks bent about 90 degrees froward (toward chain rings). Probably will break if bent back into correct position.

If you have more troubles with it or with finding a replacement, PM me your address. I'll send you one of the best performing derailleurs ever built and particular favorite of mine, gratis. The venerable Suntour SL. Bulletproofa and still looks good in a steampunk kind of way.

Best,

Julian

Julian - thanks for your very generous offer! I'm in the UK so you need to be careful how much gratis you offer, might end up costing you more than you bargained for! I'm in the South East, and my postcode (Zip) starts 'TN', but I'm guessing the TN in your avatar profile means Tennessee, not Tonbridge! LOL! :-)

As it happens I have managed to bend the arm back up. Probably not to it's original position, but enough that the cable doesn't need anywhere near as much leverage and I'm now successfully changing the front chainring again. Just need to get the derailleur calibrated now. I think the still slightly bent arm is putting it out a bit.

When adjusting the derailleur, should the chain always be free of rubbing in every chainring/sprocket combo, or is it to be expected that some combinations will always mean the chain is rubbing with the derailleur?

Ahhh, if we were only neighbors....

It's possible under some circumstances of synergy combining componentry selection, chain width, gearing, and skill to set up for cross chaining with full clearance on both side of FD. Still, for good and obvious reasons it not a necessity nor even recommended. More succinctly, in answer to your question, the latter.

Good luck on your fix.

Best,

J

Yes then you could show me what I'm doing in real life... it's getting dangerous balancing my bike, tools, laptop, keeping the excess cable out of the chainring while testing setup!

As I suspected. Just getting used to road bikes really, my old mountain bike was so knackered all the gears made a hell of a racket, so any pleasant sounding combos are now a bonus!

Thanks for all your help.