I recently purchased an old road bike from a thrift shop for $15.00 bucks. It has downtube shifters, two rings in front and a front deraillieur of a design that I'm not familiar with. It has a shaft that moves horizontally through the body of the deraillieur. Can anyone explain to me how to tune this front d? Also, any info anyone has on Bottechia would be appreciated. Thanks, Gurgus.