difference between Slx shifters rd663 and rd670

boristhespie

Really struggling to get grips around Shimano model numbers.

I have slx chainset, building bike up and want gearing to fit my 3x10 setup but just don't get the model numbers. They need to be dynasys.

So what is the difference between slx rear mech models rdm663sgs and rdm670sgs?

Also any advice on front mech, casettes and chains would be welcome. It's for a bluepigx

cooldad

Surely those model numbers are rear mechs, not shifters? (RD)
They are both 10 speed, one is the new model, one the old.

boristhespie

Yup rear mechs. My mistake, buying shifters too, so were obviously in my bonce. So the difference is the 663 preceded the 670 and therefore the 670 is newer model.

Chunkers1980

Yep. New one looks a lot better. Make sure you buy the correct length for your setup.

RevellRider

SGS will be long enough for a 3x10 setup. If you're buying new why not get the M675, which is the clutch version?

boristhespie

What's the benefits of a clutch.

Chunkers1980

Reduced/zero chain slap, and the chain is held more to the bottom of the ring.