Front derailleur rub

mcstumpy

Hi

Have taken receipt of a built up bike, ultegra and 105 11s mix to replace tiagra 4600 bike.

Chainset is 50 34, cassette is 11 28

I control front mech with a bar end friction shifter

Took new build out for first spin but think I have an adjustment required on front derailleur. I know chain rub is normal at extreme ends (50-28 Or 34-11) but on new bike it starts rubbing from halfway up the cassette when I'm on 50t ring. On 34-11 there is little or no rub.

I'm assuming this isn't normal?

Thanks

wongataa

That's not normal. Adjust the front mech.

StillGoing

You need the in line barrel adjuster for Shimano front derailleurs or you will never get the correct set up. Just in case you haven't got one fitted.

arlowood

McStumpy wrote:

Hi

Have taken receipt of a built up bike, ultegra and 105 11s mix to replace tiagra 4600 bike.

Chainset is 50 34, cassette is 11 28

I control front mech with a bar end friction shifter

Took new build out for first spin but think I have an adjustment required on front derailleur. I know chain rub is normal at extreme ends (50-28 Or 34-11) but on new bike it starts rubbing from halfway up the cassette when I'm on 50t ring. On 34-11 there is little or no rub.

I'm assuming this isn't normal?

Thanks

My guess is that with a bar end friction shifter you have lost the trim function that comes within the STI mechanism. This is an additional click on the inner paddle when in the big ring to move the FD cage a fraction inboard so that rub is eliminated when on the larger cassette cogs. Not sure how you would replicate this with your friction shifter other than trying to fiddle with the limit screw to achieve the right balance.

mcstumpy

Thanks, I seem to have managed to use the friction shifter to trim. So all sorted.