Are Shimano and SRAM 11-speed compatible?
Partly. At 11-speed road, the Shimano/SRAM chain and cassette interchange without problems. BUT the shifter and derailleur must be the SAME brand: Shimano and SRAM use different cable-pull ratios, so a Shimano shifter won't drive a SRAM derailleur correctly (and vice versa).
Standards involved
What you need — before you buy
- It depends on the exact parts: read the answer above and check the manufacturer's spec for your specific model and year.
- When in doubt, keep the same brand and generation across the components that must work together.
- Match the part to your exact hub/frame: check brand, model and year. Don't choose a freehub body or component by standard name alone.