Depends on age I suspect. If the 8 speed chain seats on the sprockets fully it should be fine. Otherwise try a wider chain. The bike appears to be too new to require a 1/8" chain which is what original derailleur 3 speeds used pre WW2 I have read.
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Gear Hubs Owned: Rohloff disc brake, SRAM iM9 disc brake, SRAM P5 freewheel, Sachs Torpedo 3 speed freewheel, NuVinci CVT, Shimano Alfine SG S-501, Sturmey Archer S5-2 Alloy. Other: 83 Colnago Super Record, Univega Via De Oro
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