Help changing front derailleur

[richstanton]

Hi, I've bought a new front derailleur for my kids bike - it's a Ridgeback MX3 from a few years back, and has been in the cellar for a few years. When we got it up, the derailleur was stiff to change up, although the cables moved freely. It was a shimano tourney, so I've tried to buy exactly the same thing, although the cable routing is slightly different - on the old derailleur the cable loops up from beneath, then over and back down to where it clamps onto the derailleur, whereas the new one seems to just attach directly from beneath. However that means that the cable rests/rubs on part of the mechanism when you shift, which can't be a good thing. It's also fairly stiff to shift still (I checked that the cables run smoothly without the derailleur), so I'm wondering if I've got the cabling route wrong, or if I've bought the wrong derailleur. Any advice welcome! I've attached a pic of the old one (taken off the bike), and the new one on the bike, with the bit where it's rubbing ringed.

Thanks for any advice!

 

[Cycleops]

Hello and to the forum.

Looks like the point where the cable secures to the clamp may be in a different position to the original causing the cable to pull across and making it rub where it wasn't rubbing before. Can't confirm as the pic of the original doesn't show this but that seems the most likely cause. Is it a 'bottom pull' derailleur?
Only thing to do is look for s derailleur which has the clamp in the same or similar position to the original. Further back would also work.
If you don't want to go to that expense you could use the existing and run the cable in a metal tube.

 

[Peter Salt]

I'm not familiar with this specific model, but Shimano derailleurs that I worked with always had 'cable converters' that you could install/orient in different ways to achieve a specific cable route and/or leverage.