Originally Posted by
dddd
I (and I suspect T-Mar) appreciate the compliments coming from Chicago!
Curiously, New 600 EX, while all-new in design, preceded the SIS era.
While certainly not the lightest 600 friction gruppo, I think of it as perhaps the pinnacle of Shimano's friction gruppos, Servo-Panta at it's very best, with robust durability, and I think newer in design than Shimano's last Dura-Ace friction gruppo.
As a serious Suntour partisan at the time, It escaped my notice. But I found a Centurion Elite RS a few years ago that was somewhat of a revelation in terms of friction shifting performance, once I updated the chain to UG Narrow (dimensionally identical to today's HG).
Oddly enough, Centurion offered bikes with both New 600EX and 600 SIS concurrently, as their prices were significantly different. The former gruppo may have had the aesthetic advantage, no? Sorry this photo isn't sharper.
Just to clarify a possible misunderstanding, 1986's 600 SIS was part of New 600EX, which had started out as friction only in the 1984 model year. In the 1986 model year it was upgraded with a SIS option consisting of the new RD-6208 rear derailleur, SL-6208 shift levers and MF-6208 freewheel. Besides SIS compatibility, the big changes for the rear derailleur was the incorporation of a slant parallelogram and cable tension adjuster. Even though the SIS levers had a friction mode, Shimano continued to offer the friction version of the levers and rear derailleur for manufacturers who were not convinced of indexed shifting and/or wanted to economize. Attached is the relevant section of the 1986 catalog page, showing the availability of both versions,so you can see the aesthetic differences. Before anybody asks, Shimano never put the "New" or "EX" designations on the actual product..1986 was also the year that Shimano literature dropped the "New" from New 600EX, reverting to just 600EX, though I still call it New 600EX to distinguish it from earlier 600EX (aka Arabesque).
Besides New 600EX, there were some other non-indexed Shimano derailleurs newly released for the 1984 model year. Most notable is Deore XT, but there were also some Light Action and/or Z-series introduced that year. There were also some new Light Action derailleurs released for the 1986 model year that were not listed a SIS compatible, though the designs certainly look SIS compatible. For instance, the 1986 RD-L525 is available in three different cage lengths but only the shortest cage version is listed as being SIS compatible. That's very perplexing.
