I know, sounds like a problem from 2004.
Anyway, my wife's Liv Devote gravel bike has 2x10 GRX with a Tiagra front mech (one with the silly looking long lever thing). It's a pig to shift, even with fresh cable and housing. Two options:
1 - Try the proper GRX front mech. Newer design, designed to work with GRX levers, might just be plain better?
2 - Is the mech fine and it's the crap internal routing at fault? Would drilling out the stops and running full length outer make a bigger difference?
Any ideas? I'm reluctant to drill the frame, but I'm wondering if the housing/routing is more at fault than the existing mech.
Worth trying the GRX mech. first.
Merlin have them for £15.
https://www.merlincycles.com/shimano-grx-rx400-front-derailleur-10-speed-244103.html
GRX is designed around a different chainline, 2.5mm further outboard than regular Shimano road stuff. What crankset is on there?
I wondered about the chainline. It's an FSA Omega with Tiagra mech. Would like to stick a GRX chainset on too as the FSA is a bit yuck. Good spot on Merlin 👍
My gravel bike had a GRX front mech with a cheapie Prowheel road chainset. Seemed to work fine, I'd try it. I then swapped the chainset for a GRX one anyway, that works fine too - it just matches now 🙂
That GRX mech was very easy to set up. Works really well.
Run a test external cable first before you start drilling frames. Doesn't even need to be ziptied to the frame, just a clean run between shifter and mech to see if the routing is the issue.
Run a test external cable first before you start drilling frames. Doesn't even need to be ziptied to the frame, just a clean run between shifter and mech to see if the routing is the issue.
I was going to suggest this.
Also, make spray a bunch of lube over it and work it back and forth to make sure it isn't stiff from exposure to the elements.
I think on those the stops are on the headtube and the inner runs inside the downtube, so it isn't really exposed to the elements. I reckon if it's still stiff with brand new cables, I'd start looking at the mech and checking the action on that.
Thanks all. Will give some these suggestions a go. Ordered the GRX mech from Merlin - for £14 it's well worth a go. And got some more cable outer to experiment with too.
I've got a 4700 front mech on one bike and a very similar looking 6800 on the other and I would say I get an appreciably better shift from the 6800, both being operated by Tiagra levers
Have you played with the little 2 position nubbin thingy below the cable clamp?
I'd suggest a fresh cable, but take it off first and give it a jolly good scrub and drown it in some form of oil first to ensure it's as free moving as possible, I'm not convinced a full length outer solves all issues TBH.
That said if a GRX mech is cheap, it's probably worth a try.
i have a GRX 400 front mech on my gravel bike with GRX400 levers and it shifts just fine - given how cheap the GRX400 front mech is i would be tempted to try that 1st ( after verifying that the inner cable is running free even under tension)
