[akelly524]

I’ve got 16 speed shimano claris and when I’m in the highest possible gear the chain rubs the outboard side of the derailleur. I’ve tried adjusting cable tension tension and limit screws and even started from scratch but the derailleur rubs against the crank arm when in the right position relative to the chain. I’m considering bringing to my lbs but would rather not as I want to learn how to fix it in future. Has anyone got any similar experiences or suggestions as they would be greatly appreciated

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[akelly524]

Just 20 quid. Great value in
Just 20 quid. Great value in my mind but may be because of square taper bb not being as snazzy and therefore expensive as other bbs

[kwi]

Knowing when to admit defeat
Knowing when to admit defeat and get help is probably the most underrated workshop skill you can have. Did it hurt the wallet much?

[akelly524]

I brought it to the lbs. The
I brought it to the lbs. The bb was knackered and the derailleur hangar was also bent. Probably my fault :S

[akelly524]

It’s all of the derailleur
It’s all of the derailleur though I’ve tried the realignment

[kwi]

2 Wheeled Idiot wrote:If it

2 Wheeled Idiot wrote:

If it is just the very back part of the derailleur hitting the cranks, it could be that it is angled slightly wrong, unbolt the derailleur and angle the ‘tail’ inwards..again it has very slight clearances so may need a bit of fiddling.

Or if it’s just the tail hitting the chain adjust it outwards.

[2 Wheeled Idiot]

If it is just the very back
If it is just the very back part of the derailleur hitting the cranks, it could be that it is angled slightly wrong, unbolt the derailleur and angle the ‘tail’ inwards..again it has very slight clearances so may need a bit of fiddling.

[Toro Toro]

Tricky. The thing I’ve found
Tricky. The thing I’ve found with limit-screws is you need to be patient and trim them no more than a quarter-turn at a time; the margin between my rear derailleur twanging the spokes and not making it all the way to the lowest gear is incredibly fine.

Is there a point at which your FD is *both* rubbing the chain *and* striking the crank? Not necessarily at the same time, but for instance doing one when seated and the other out of the saddle? If so, then the problem may be a bent crank; one way or another it’s probably not fixable just by tweaking derailleur settings.

If not, I’d say to keep trying with very fine adjustments, and a lot of patience.

[akelly524]

I’m running the 48t ring
I’m running the 48t ring because of U14 gearing restrictions. I’ll be changing to a 52t at the start of next year so I might stick it out til then

[kwi]

If the crank is striking the
If the crank is striking the FD when it’s correctly aligned (In relation to the large chainring.) either the crank is bent or the chainrings are assembled incorrectly.

Sorry just read you next post. 48t outer chainring? That could be your issue too, it could mean lowering the FD to a point where there is not enough clearance between the chainring and crank, so if your hell bent on running 48t you may need new cranks.

[akelly524]

Btw I’ve got a 48 tooth front
Btw I’ve got a 48 tooth front chainring for racing if that makes any difference

[Author]

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