Originally Posted by
clubman
One anomaly was the Biopace FC-B124 crankset, circa 85. It had all the elements of a Deore touring triple without the name while the finish was less refined. Not sure what other components were specced with it.
From ebay (and my stash)
When 1st generation Deore XT was introduced for the 1983 model year, it carried over the FC_DE30, 5-pin, Dyna-Drive, triple crankset that had been introduced on the 1981 Deore touring group. When Shimano introduced New 600EX for the 1984 model year, it included a nFC-6206 triple crankset, which was typically spec'd with Deore XT though 1986.
The FC-B124 was not introduced until the 1987 model year, by which time 2nd generation Deore XT was available and had a dedicated FC-M730 crankset. At a claimed 752g, the FC-B124 was significantly heavier than the FC-M730 (707g) or FC-6206 (700g). Based on the weight different, I suspect that it was cast rather than forged. The FC-B124 was typically paired with the new Deore (MT60 series) of ATB components, which in 1987 had yet to receive a matching crankset. It was also sometimes seen on ATBs with Light Action derailleurs.