Chain rubbing on front mech

[Trigger369]

Past few rides my chain has been rubbing on the front derialleur . It's rubbing on the right side of the derialleur if your sitting on the bike looking down . Only happens when in the front big ring and the middle to the smallest cog at the back . How do I adjust this properly .?
Thoufit i would ask here before Google tells me to strip the whole thing and start agian lol.

 

[Vantage]

It sounds a though the cable has slipped at bit. Depending on your sifters, there will either be an adjustment barrel on the shifter itself or on one of the cable guides on the frame. Turn it anticlockwise and tighten up the cable clamp bolt on the derailleur.

 

[Heltor Chasca]

Or is it something like a Shimano 105 with trim function? I set mine with a double click/trim on the big ring.

 

[Ajax Bay]

@Cycleops
First off unscrew the H limit screw a half turn and see if that makes any/enough difference. If not enough, another half turn. If it makes no difference. Undo cable clamping bolt and start again. Fiddling with barrel adjusters will likely not sort this (half a cassette's worth of rub).
Must admit surprise OP has been prepared to ride several times with their FD maladjusted like this. Must have been irritating at any speed (ie flat/downhill).

 

[Will Spin]

Find the manufacturer's instructions e.g. if it's Shimano, check here. You'll find it difficult to get it set up properly unless you follow their instructions.

 

[smutchin]

First off unscrew the H limit screw a half turn and see if that makes any/enough difference.

I'd be wary of doing this. If it was working fine until recently, it's unlikely that the H limit screw has tightened itself up to cause this problem. And loosening off the screw introduces the risk of overshifting and dropping the chain.

@Trigger369 My first thought would be to increase the cable tension slightly (as per @Vantage's comment). Easy to do if inline adjusters are fitted (often found on the down tube cable stops for bikes with external cable routing), otherwise requires adjusting at the mech itself by undoing the pinch bolt, pulling the cable and retightening it. (I'd recommend following the procedure as described on the Park Tool website: https://www.parktool.com/blog/repair-help/front-derailleur-adjustment#article-section-8 )

 

[Ajax Bay]

I'd be wary of doing this. If it was working fine until recently, it's unlikely that the H limit screw has tightened itself up to cause this problem. And loosening off the screw introduces the risk of overshifting and dropping the chain.

Where does the OP say that "it was working fine until recently"? (I note your conditional clause.)
I reckoned that if it's rubbing at half cassette there is little likelihood of overshifting, even after half a turn. OP's problem is the reverse. As I said: "see if that makes any/enough difference." If it doesn't make a difference, screw it back up (half a turn and "undo cable clamping bolt and start again." We're saying the same except I suggest checking the adjustment of the limit screw FIRST.

 

[smutchin]

Where does the OP say that "it was working fine until recently"? (I note your conditional clause.)

Well, the OP says this problem has occurred on the "past few rides" so I'm guessing that means it didn't happen on previous rides. That's why I'm assuming it's most likely to do with cable tension.

We're saying the same except I suggest checking the adjustment of the limit screw FIRST.

Fair enough. You're probably right that half a turn won't hurt. I would avoid messing with limit screws as a general rule though - once set correctly, they shouldn't need adjusting again unless you've changed something else in your set-up.

 

[Trigger369]

Guys . Just getting to look at the bike now . Thank you for all your comments and links.
I've learned a bit here today . I was trying to turn the cable barrell and it wouldn't turn all because I had the chain in the big ring at the front and it easily turns when in the small ring . Turns out that's all was needed to fix the rubbing a few turns of the adjustment barrell .
Thanks agian all .

 

[wonderloaf]

Guys . Just getting to look at the bike now . Thank you for all your comments and links.
I've learned a bit here today . I was trying to turn the cable barrell and it wouldn't turn all because I had the chain in the big ring at the front and it easily turns when in the small ring . Turns out that's all was needed to fix the rubbing a few turns of the adjustment barrell .
Thanks agian all .

Thanks for letting us know the outcome, I now know what to do should the same happen to me!