So, this might have happened... NBD - 2016 Fuji Touring workhorse

[Gunk]

I can say with absolute certainty that Sora STIs will not play well with other than a road FD. Spent many an hour trying, trust me. Get a Sora FD.

I couldn’t get Sora 2x9 Brifters to work with early an 105 front mech, I farted about for hours, in the end I slapped a used Sora on and it all worked perfectly in seconds. Not all Shimano 9 speed is cross compatible.

 

[wafter]

I can say with absolute certainty that Sora STIs will not play well with other than a road FD. Spent many an hour trying, trust me. Get a Sora FD.

I couldn’t get Sora 2x9 Brifters to work with early an 105 front mech, I farted about for hours, in the end I slapped a used Sora on and it all worked perfectly in seconds. Not all Shimano 9 speed is cross compatible.

That's odd as AFAIK 9sp stuff should all be compatable... what were the problems you were each having / do you know what the specific problem is?

 

[Ming the Merciless]

Compatibility details

https://productinfo.shimano.com/pdfs/product/archive/2023-2024_Compatibility_v030_en.pdf