Chain rubbing on front mech

Uli

Hello good people,
I need a bit of advice before I use hammer to "fix" front mech. The problem is chain rubbing on inside plate of front derailleur when in middle cog. The setup is 3x 8 and it is Shimano Altus mech and SRAM shifter and crankset. It rubs in all gears below 7 at rear. As it rubs on inside plate I was trying to loose the cable, but if I turn the barrel just 1/8 then it doesn't shift from 1 to 2 in the front. I was trying to adjust the tension in 1st gear so the cage moves a little outside but then again cant' sort out the middle cog. I can get perfect shifting but only with rubbing. The most annoying thing is that it was completely fine until now. Any ideas what else can I try?
Thanks

supersonic

Are the limit stops set correctly? Mech should also clear the outer ring by about 2mm, and be aligned straight.

Uli

Well, it seems they are. The 1st and 3rd gear shift with no issues and they get OK clearance for rear gears. The cage is just above the biggest cog. I didn't want to start moving it around as it was fine before. The all rubbing business developed today during the ride.

gezebo

Front Mechs can be quite fiddly to set up compared to the rear, sometimes they get knocked without realising. You could try slackening the clamp (a little) and twisting the cage inwards (very slightly) or outwards and seeing if that makes a difference.

Something to try if the tensioning is/was correct.

Uli

I may try that. TBH the bike was never setup correctly. It is Carrera Vulcan and I helped my friend to collect it from obvious retailer. The gearing was not set up so I did it first time myself and it was OK for a while. Yesterday I found that brake calipers are fixed with different bolts (one too short and one is split). Some bolts have damged heads so removing them now with allen key is a challenge. There was also delay with collection cos disk rotor was bend so they had to swap it from other bike. Just few things in case anybody is thinking about buying a bike from the above mentioned retailer.

The Rookie

Most that stuff is done at the factory, not the retailer, so your point was.......

Uli

My point was that if you collect the bike they promise it is going to be road ready which is great especially in case of ladies bikes. The bike comes in the box to the shop so I believe it was their responsibility to make sure that gears can shift and brake calipers are tightened with correct bolts and don't rattle. The mistake was that I didn't check the bike correctly at the shop- something one may remember in the future.
Anyway that is not what the topic was about and I just made a digression.

Chunkers1980

How about you start again? What are your actual problems

Bolts can be different lengths as the bracket are often thicker on the top.

Twelly

Uli wrote:

My point was that if you collect the bike they promise it is going to be road ready which is great especially in case of ladies bikes.

If you are implying girls can't set up bikes themselves I think you are on thin ice on this forum. There are a couple of ladies here who would say different I'm sure.

Uli wrote:

collect it from obvious retailer.

'Halfords' isn't a censored word.

Uli wrote:

There was also delay with collection cos disk rotor was bend so they had to swap it from other bike. Just few things in case anybody is thinking about buying a bike from the above mentioned retailer.

Would you rather they let you pick it up earlier with possibly faulty brakes?

Uli wrote:

I believe it was their responsibility to make sure that gears can shift and brake calipers are tightened with correct bolts and don't rattle.

Actually I would say it is your responsibility to check your bike before you ride it - whether that is when you have just bought it or 10 years down the line.

Another 'Halfrauds' thread with no real substance. You have used your bike, bikes need regular adjustment and maintainence. If you can't do this yourself, take your bike to Halfords (or another LBS if you'd prefer) and have them adjust it for a couple of quid.

Uli

OK. Back to first post. I will try explaining again. The issue is with front mech. Shifting itself is fine but chain is heavily rubbing on inside plate of the derailleur cage when on middle cog. It doesn't really matter what gear is selected at rear. It appears the cage is moving far outside during 1 to 2 shift but if I try to loose the cable just 1/8 of a barrel turn then it doesn't shift from 1st to 2 nd. (front). The 1st and 3rd are fine for their rear ratio. I was trying to change cage position while in the 1st but it doesn't really change anything.
The setup is described in my first post. Let me know if something is not clear as it is little tricky to explain.
Thanks

@TwellySmat
The girl bike was for- can't. Like I said it was digression from main topic so could you let it go? Believe or not but that was shabby job.

Chunkers1980

Have you read the Park Tool guide?

supersonic

The mech needs to be set up from scratch. As above, Park Tools has the best guide.

Uli

OK. I just had another look at it and I found the answer. Instead of using shifter I start playing with the cable and it got better. Then I swapped the shifter with Alivio one from another bike and voila. All is shifting nice without any rubbing nonsense. I will test SRAM shifter later on on another bike.