How come not needed for CX?
Mech with a clutch is enough to keep the chain on. CX bikes being what they are you aren't going to be getting big hits that can shake it lose.
If you don't have a clutch a basic chain keeper will do.
@Howard started
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Mech with a clutch is enough to keep the chain on. CX bikes being what they are you aren't going to be getting big hits that can shake it lose.
If you don't have a clutch a basic chain keeper will do.