Answer from BIKE test manager Christoph Listmann:
"The new 11-speed cassette from Shimano also works with "old" cranks and chainrings because the internal width of the 11-speed chain has remained the same. The Shimano 11-speed cassette also fits on conventional 10-speed hubs. You therefore need an 11-speed sprocket set, rear derailleur and shifters as well as the appropriate chain for the conversion. In our experience, the Shimano rear derailleur can be combined with a wide variety of crank manufacturers at the front - for example with the 22/36 crank from Sram to get a powerful climbing gear."
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