I'm trying to finish the build on my old-school road bike in the event that Spring ever actually arrives here in Chicago.
I'm having trouble adjusting my rear derailleur and would be grateful if someone can advise me. I paired up a (new old stock) Shimano 600 SIS 6-speed rear derailleur with 6-speed SIS downtube shifters. These should be a perfect match because they're RD-6208 and SL-6208 respectively. I'm using a Shimano 6-speed indexed freewheel (14-16-18-21-24-28) with the original Sakae crankset (40/52) and a new SRAM Power Chain rated for 6-7-8 speeds.
Two cogs are causing me trouble. When I shift down (toward the larger cog,) the chain jumps over the 18 to the 21. When I shift up (toward the smaller cog,) it jumps the 21 to the 18. I've adjusted the upper and lower limit screws, the cable tension, the chain length and even the "B" screw. I'm running out of things to adjust.