Cross-chain Rubbing Problem

Hi all, I recently swapped three ring crankset and BB with 2 ring setup. I have triple STI, but I tensioned it to work like a double; still have long cage triple rear derailleur and triple front derailleur. The front der. shifts back and forth without any problem, but now chain rubbs against front der. a little more. On 39T, my chain starts rubbing the front der. from the third outward cog on. No rubbing on small chain ring with largest cog, or large ring with smallest cog. Do I just live with this situation or can anything be done? Thanks in advance!

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Play with the tension a little more to dial it in, also your indexing on the triple shifter might be slightly different than that of a double, but you should be able to trim out the rub with your shifter if necessary, I have set up plenty of bikes with a double, mostly compact, using triple shifters and der. with no problems.

You using the granny and middle ring positions in the shifter and the trim function?

Thank you, whitey. will try to fine-tune the tension

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I never really understood how to 'trim.' Right, I only have one click either way on my front STI.

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