Shimano Ultegra/600 downtube shifter issue.


Gold Trader
MacRetro Rider
Orange 🍊 Fan
I'm currently swapping out the Ultegra 6500 groupset on my '92/93 Orange Dynamo for a more period correct 6400 600 "Tricolor" group, and I'm having issues with the downtube shifters.
The 6500 group currently has 9-speed "brifters" and cable stops on the downtube mounts.

Firstly, I can't seem to get the silver backing plates off the studs.

Secondly, if I do get the backing plates off, the ones from the 600 shifters won't fit the tube profile of the aluminium frame (they came from a steel framed donor bike).

Lastly, the 600 shifters won't fit on the current backing plates as they're of a different design.

So... As I'm pretty sure they didn't make 6500 downtube shifters, what are my options? Is there something that will fit & work with the 600 drivetrain? Any tips for removing the backing plates? I assume they DO come off?

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All you need are two flat backed washers instead of the curved washers that will fit onto the existing frame shifter mounts to get the shifters to fit. No drilling, cutting or hacking required. I can post up some photos later to explain if needed.