I'm looking at getting a pair of ST-6603 brifters for use on my touring bike. I currently have an older biopace triple upfront, and a 8sp cassette in back. I will eventually be upgrading to a 10sp cassette.
My question, can I use the brifters with my current drivetrain and just not have the last two "clicks" on the back? Or will the ratios be all off on the rear cassette? Seems like SB states that generally they are forgiving enough that they would probably work (for about the month or two before getting the 10sp cassette). Also will the triple front work with my biopace triple (its old).
If they aren't compatible, is there anything against using brifters only as aero brake levers (and not even have the shift cables attached), is anything going to get knocked loose as a result of not having tension on the shifting segments of the levers themselves?
Its just not in the budget to get a new cassette (or necessary) at the same time I get the brifters.