I have a customized Salsa Journeyman Claris. How small can I go for my small chainring? I'm not sure how to verify compatibility It's a Salsa Journeyman Claris drop bar 650b converted to flat. The flat and drop frames are the same, but the drop comes with road bike components.
I have already upgraded a Sunrace 11-40t cassette to the rear with the help of a Wolftooth Components Roadlink which leads me to about 20.06 gear inches.
I currently have an FSA Adventure Tempo 30t/46t crankset in the front paired with the Shimano Claris front derailleur but was hoping to drop my small chainring to around 24t for the sweet, sweet, 16.5 gear inches.
Is it as simple as an easy cog swap and a chain? I'm not sure what parts need to be compatible to make it work.
Cheers all!
The crank chainring bolt center diameter (diameter of a circle that passes through the center of the chainring bolts) is what limits the maximum and minimum chainring sizes.
It's likely that you will not be able to get a much smaller chainring on the FSA crank. To get to 24 tooth small rings you need an mountain bike crank. 'Two-piece' MTB cranks made for external bearings in threaded frames or press-fit bearings are not compatible with road frames as they require a wider bottom bracket shell. The FSA Tempo crank is three-piece for a tapered axle cassette type BB though, so you made have luck finding a three-piece MTB double crank with the chainring sizes you want. Bear in mind you will probably have to change the BB as different crank models require different BB axles lengths.
Check that your front derailleur can accommodate the difference between chainrings on the crank you select, and can be dropped far enough down the seatpost.