I am comptemplating upgrades to an old(er) RaleighUSA Technium road bike which has the original factory spec Shimano Exage Triple derailleurs. I'm pretty certain the rear derailleur is SIS, even though it's not stamped with the SIS logo like the front. Assuming it is, I'm wondering if SIS derailleurs, especially the rear ones, would be compatible with Sora STI Triple levers, or if I'll need to replace the deraillueurs as well as the levers. I did this rather easily with my Cannondale but that's because the existing RSX kit was also STI. Any advise/feedback would be appreciated.