Front derailleur help

For discussions about bikes and equipment.
Fraz101
Posts: 146
Joined: 15 Feb 2018, 12:47pm

Front derailleur help

Postby Fraz101 » 1 Sep 2018, 8:34am

I need a new front mech for my commuter mtb as it keeps sticking and I’m fed up trying to free it off, but I’m unsure what my options are.....

It is a 7x3 speed shimano tourney mech it is a band on and the cable comes down the frame to attach to mech.

Do I need to know anything else to get the correct mech?

I would like to try an upgraded component if possible.

Brucey
Posts: 43055
Joined: 4 Jan 2012, 6:25pm

Re: Front derailleur help

Postby Brucey » 1 Sep 2018, 9:22am

IIRC you have some form of Giant 'rock', no?

Like this?

Image

if so you need a
-top pull
-top swing
- MTB type
with a band diameter that matches your frame

Of those such, some won't be suitable for your bike by virtue of chainstay angle or chainring size, or cage width etc.

FWIW any FD on a bike without mudguards/with draggy cables is at risk of seizing up. When you unseize a FD there is little point in freeing it off enough so that it just works; it will soon seize up again. You need to free it off completely and then lube it with something thicker than WD40. Cleaning the mud off it and giving it a squirt of water displacer whenever it gets wet is an excellent idea. Mudguards that protect the FD are an even better one.

Spending lots on a 'better' FD is one of the least effective ways of improving your bike. Since you have 7s gearing, your range of new FDs is restricted; if you must have a posh one you are looking at buying a NOS/used 7/8s one; 9s might work for you but 10s or 11s are not going to work very well.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

Fraz101
Posts: 146
Joined: 15 Feb 2018, 12:47pm

Re: Front derailleur help

Postby Fraz101 » 1 Sep 2018, 9:50am

Yes that’s the bike I have.

Sounds like I would be best just doing a like for like replacement?

Brucey
Posts: 43055
Joined: 4 Jan 2012, 6:25pm

Re: Front derailleur help

Postby Brucey » 1 Sep 2018, 10:14am

Fraz101 wrote:...Sounds like I would be best just doing a like for like replacement?


that would certainly be easiest. Just be sure that the problems are not being caused/helped by (say) a draggy cable first; remember that the FD spring has to move the FD and pull the cable back through the housings; these need frequent maintenance if they are to stay drag-free.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~