Claris R2000 on a 10 speed 105
I have a 2010 Cube Attempt with a the older 10 speed 105 groupset .
I managed to break the rear mech and when in for repair I was told the new 105 rear derailleur isn’t compatible anymore as the new 105 is 11speed .
The workaround was to put a Claris r2000 on which is 8 speed . He assures me it will work perfect . I took it for a short spin and noticed it wasn’t as smooth but did seem to shift across the
10 gears ok
I’m looking for thoughts on this . Is he right or should I source an older 105 rear derailleur and insist on taking the Claris back off ?