After about 500kms on a stock giant contend I noticed my crankset wobble from side to side and making sounds it has those octalink style or square tapered bb's(not sure) WC I'm never comfortable with, anyway I plan to switch to a 105 or tiagra crankset with appropriate BB. Im sticking with the same gearing 50/34. I checked shimanos site and says 105/tiagra are 10spd cranks I have a 6 spd. Would there be a problem with the chain or shifting if I just change the crankset?