Why..........?
Find some newer Shimano Index Down Tube shifters - I still use them.
Why..........?
Find some newer Shimano Index Down Tube shifters - I still use them.
I'm guessing by the "arabesque" 600 levers yours is of a decent quality though?
You could well end up looking at a complete change of drive train - including wheels, cassette, chainset, mechs etc
It can be done... I've done it, and happily run a modern 9 speed Shimano drive-train from 10 speed Campag levers....but it is NOT cheap, (I spent more than the original purchase price of the new bike in 1988) so possibly not worth it unless a really good frame.
The problem is that there are no frame bosses on the bike. There's a chance you might find a suitable lump on the lever band if you take the levers off, but otherwise down tube cable stops might be difficult.