Front Derailer Rubbing

[Slipery99]

I know there are a lot of threads on front derailer's rubbing and I have taken a look at the guides, etc.

I ended up spending about 4 hours straight one Saturday trying to adjust everything but I gave up and brought it to a shop. This was about 1.5 months ago.. It came out of the shop still broken, so I had to bring it in again to the same place (just spent $60 there, so wanted to make sure I was getting service for my money).

Anyways, I bike about 10km every day for work/school, and I was just adjusting my bike seat and as I was testing out the seat around the apartment I noticed rubbing.. I get some rubbing on 3/6 to 3/8 on the outside of the derailleur. It appears as if it won't move far enough to the right (away from the bike) in order to prevent rubbing. I bike mostly in 3-7 on flats, so I would really like to fix this.

Is this anything I can do a quick fix with at home (adjust cable tension or high/lows quickly)? Or should I bring it in again.. I am not sure if I can explain to them that they just fixed this issue 45 days ago, but I supposed while I am biking around the city lots of different things can happen so the bike so the shop isn't really responsible.

The bike is a Giant hybrid bike with shimano derailleur

[DaveM]

With the derailleur in the outermost position, pull on the cable itself where it runs along the frame. If the derailleur moves farther out, you can add tension to the cable to make the derailleur move farther out. If it doesn't move, try backing out the high limit screw a little bit.

If it rubs on only part of the rotation, it sounds like your chainrings are bent or the whole crank is slightly angled. This will make it hard to adjust everything to get no rubbing, but clean shifts without the chain falling off.

Also, check that the outer plate of the derailleur is parallel to the outer chainring. It's easy to bump the der. and bend it in a little. This could be why the rubbing started up again.