Front Derailleur

mustol

Changing between the chainrings on my Specialized Allez triple is generally fine, but when I change from the small chainring (30) to the middle chainring (42), it jumps/springs dramatically into place with quite a clunk (it wasn't like it when I first got the bike). Changing up from middle to large is pretty smooth. I've tried adjusting cable tension using the barrel adjuster, but there is hardly any slack to adjust. Do I need to loosen the cable or could there be another explanation?

ugo.santalucia

Changing from a small ring to a larger one is generally not cause of clunks as you are pulling the cable. If the process is noisy it could be due to a number of reasons

1) Wrong tension, likely too little
2) Cable does not run smoothly
3) Derailleur is dirty

I suggest you give a good clean/lube then shift to the small ring, open the screw that holds the cable, tension it by hand and lock it in place. That should sort out any problem. The barrel adjuster on the front derailleur is pretty much useless, old bikes didn't even have it

To prevent anyone of the "worn components brigade", it is not a chain/chainring/cassette wear problem... never...