I really feel like I should be able to figure this out on my own, but can’t find very many resources, so i wanted to ask here.
I have a gravel bike with a GRX-400 2x10 setup with a 46-30 on the front. I would like some more top end as where I live is very flat and I use a limited range of the available gearing, however the 46-30 is Shimano’s only offering in the GRX series. If I wanted to swap it to the Tiagra 50-34, would it require me changing the front derailleur? Any other options for changing the front cranks without changing the derailleur?
Thanks in advance for any input.
A non grx crankset will not have the appropriate offset for the grx FD. You might be able to adjust it enough but wouldn’t be a guarantee. There is a 48-31 grx crankset.
Have your shop see if they can order the 48-31 rings.
Thank you for the response. Supposedly the GRX400 FD is only good for a 16 tooth gap. The GRX800 can accommodate the 17 tooth differential of the 48/31.
I think going tiaga may be my best bet?
Really weird you bring this up, I’ve been thinking the same thing. With a tailwind I’m spinning out on my 46/31 on the road (have an Orbea Terra that I switch the wheels out on) and I’m think I may for the summer swap in a Tiagra 50/34 with an old 105 10 speed front derailleur I have. I’ve used 10 and 11 speed front derailleurs interchangeably with no issue in the past.
GRX chain line is wider than road chain lines by 2.5mm. A road derailleur won’t work well, if at all, as it can’t reach the big ring if you stick with a GRX crank set.