[Closed] Front Mech Question

34.9mm is the diameter of the front mech clamp that clamps onto the seat tube (i.e. it's the diameter of the seat tube). Top pull means that the cable pulls the mech from the top. Low or high clamp refers to the position of the clamp relative to the cage. High clamp means the clamp is higher than the cage (pivots) whereas low clamp means the clamp is lower than the cage (pivots).

I prefer high clamp front mechs to low clamp as they seem to last longer but not all frames can accomodate high clamps. High clamps can foul with the bottle cage on hardtails and the linkages on full sussers. If in doubt, stick with whatever you've already got.

Sram and Shimano front mechs are interchangeable unlike their rear mechs.

Thanks Sum, that makes more sense now 🙂

right some mechs come in set sizes but most come in a large clamp and then use spacers/shims to clamp on smaller tubes. so one size fit all so to speak.
Low or High clamp, is where it is clamped on the frame, low is normally clamp same sort of hight as the granny ring, and below the pivots of the mech.
High clamp is clamped on the frame above the big ring and above the mech pitots.

BUT it is the FRAME that noramlly determines what mech to get, a lot of full sus frame with a bend low down in the seat tube would mean u need a low clamp.

As for top pull, most mechs now come as duel pull meaning they can work from cable from the top or cable from the bottom.

Hope that helps

not much you can add to above realy except that some front mechs are top or bottom pull which is handy if you change to a frame that is opposite to the one you have.

Thanks All, I now think I know what I'm looking at/for 🙂