Which belt should be on a viking mb 655.1 vr serial 433674655 current belt fitted is 6350-704-2100 but doesn't drive properly. this isn't the part number listed on the diagram for it.
I have had a look for you and this should be the correct belt you need for your machine:
https://www.lsengineers.co.uk/belt-genuine-stihl-no-6360-704-2111.html
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