Chain rub on biggest and smallest cog

Matt12345

I keep getting chain rub on the front derailleur when on the 2 biggest sprockets (2 lowest years) on the small ring and when I'm also on the smallest sprocket on the small ring.

I have tried changing limit screws, tension and even moved the derailleur position. I understand you will get some rub in the smallest sprocket and smallest ring but why am I getting rub on my 2 smallest gears?

fat daddy

you might need to align your front derailleur

Bobbinogs

If you are using Shimano are you sure it cannot be solved by using the manual trim? There are two clicks on the LH inner shifter: one to trim, one to drop. Trim should always be used for the smaller cogs. Obviously Di now does this automatically.

StillGoing

If its Shimano, you often need to use the in line barrel adjuster to dial out the last bit of rub.

svetty

When you say it rubs in small:small are you sure it's rubbing on the mech cage and not the inner surface of the teeth of the big ring?

Bobbinogs

Ah yes, read this one too quickly. Obviously trim only affects Big on the front and the bigger cogs at the back, ignore my post.

cycleclinic

with the cable unhooked and the chain on the big cog at the back set the mech allignment and limit screw so the chain does not rub the cage. attache the cable and ensure it is taught and all should be well.