I am assuming that the old Sachs was compatible with Shimano for cable pull. You can certainly check that easy enough.

Shimano rear derailleur - 8 and 9 are interchangeable, the only difference was in the shifter.

I like the old XT M735 or M739, not sure what the difference is between them.



In the photo you can't see the white print on the black because of poor lighting, but that derailleur looks pretty nice. I have bought three on Ebay used, two are currently on bikes and the third is one I bought as a backup, or for my next project. If you get a used one, I suggest you remove and regrease each jockey pulley, that is a part that users rarely lube so it likely is overdue when you get it. Do one pulley at a time so you do not accidentally mix up the parts, the upper and lower have some different parts.

Go on Ebay and do a search for rear derailleur (m735,m737,m739) but look hard at the photos and try to get a long cage one that looks like it has low mileage and is not beat up very much. These have been around for a long time, so some of them have had a lot of use.

I like the old Suntour front derailleurs that are high normal, but you probably have your own preference for the front derailleur. Plus if your shifter is indexed, it might not be compatible with the vintage Suntours. So, pick a derailleur that would work with your shifter.

Rear cassette, I use Sram 11/32.

Chains, I use the thinner 8 speed KMC chains, the cheapest ones I can get. When I say the thinner chains, this link should clarify what I mean:

8 Speed & Below Archives » KMC Chain

The chains that use the Missing Link II are thinner than the ones that use the other link.

MissingLink II » KMC Chain

Crankset, I prefer a road crank but I am sure you will use a mountain bike crank. So, I won't bother going into detail.

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EDIT: After I wrote the above, I got curious so I did a few google searches for research. Some older Sachs shifters had Campy cable pull, some newer ones had Shimano cable pull. If you have a friend with an 8 speed Shimano system bike, you might want to borrow it and put it in a work stand, then put a cable into your 8 speed shifter and hook up that cable to the Shimano derailleur and while the bike is still in the work stand, run thru the gears and see if your Sachs shifter truely has the same cable pull as Shimano 8 speed shifters by checking how well it shifts.

Good luck. I hope it is Shimano cable pull, I suspect you have no interest in building up a bike with Campy components given that you are a bikepacker. If it is Campy compatible, you would probably need a Jtek adapter to make it work with Shimano system. And realistically, a twist grip shifter would look pretty odd with Campy components.