Originally Posted by
ksryder
If it's a year-old bike then it's most likely 5800. But the sure way to tell is if it's 11-speed, then it's 5800.
You should be able to pedal backwards unless you're doing it while shifting.
My experience with dropped chains is it's usually a worn chainring, but could also be a worn cassette, or a worn chain. It could also be front or rear derailleur adjustment issues, or an incorrect chain length issue.
Check out Park Tool and Sheldon Brown and start inspecting/addressing each potential issue. Do one thing at a time so you eliminate variables.
Or, find a new shop.
5800 .. Is it?
How many non-Shimano parts are on there. Its throwing a KMC chain form a set of Praxis rings with only the FD being Shimano, - Either the 5800, 5801 or R7000.
Imo its hard to fault Shimano here.
That said, my Fuji has a similar setup. Praxis buzz rings, a KMC chain, FD4700 and ST4700. Works fine, for now. I do tend to reduce crank torque when changing the rings, to prevent the chain from slipping.
My other bike is all Tiaga 4700. None of them have ever thrown the chain.