Hi, this is my first post. havnt got any much info any where, but here it goes.

recently i bought a Bianchi Pista sei giorni 2011 full bike from another party. so i've also upgraded a few parts like the crankset to a sram omnium. after the installation, i noticed that i couldn't straighten and tighten my chain how it used to be. if i tension the rear wheel, the wheel will slide to the left, if i straighten my wheels and tighten the bolts, my chain goes lose. it did not happen with my previous stock crankset which was a truvativ touro 1.1. though it was quite loose, but it was still in cycling conditions. whenever i cycle, there was this feeling of the chain and cog been rub together( not smooth when pedaling)

and so after, i also upgraded my wheels to to a mavic ellipse wheelset with a new cog. this time it was worst, i was very hard to tension my chain and centering my wheels at the same time. this time, when i center my wheels and tighten, chain will go even more loose which was also not in riding condition.

i had no choice but to bring it to a mechanic.so he actually helped me on adjusting. he did made it centered and a tension chain but it took him almost 1/2hr do make it perfect. but there was still abit of rubbing on the cog and chain.

so my conclusion was, is it normal that this is how i should be tighten my rear wheel? taking almost half an hour to perfect it? or was my bottom bracket not suited for this frame. all the problem came after i changed my crankset. wheels not aligned and noises on the drivetrain when doing some heavy pedaling. with my previous crankset, i had no problem tightening and aligning my rear wheels with problems.

is there anyone who previously owned a bianchi pista sei giorni 2011 also had this problem after changing a crankset?