GRX front shifting ...
 

[Closed] GRX front shifting issues - anyone else?

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Offline  13thfloormonk
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Absolutely zero issue with 105 and Ultegra front shifting on my two road bkkes, and until recently my GRX shifting was spot on too, but after the R7000 shifter died and was replaced (warranty) I've never got it quite as good.

Basically the 'trim' shifts don't really do anything, and the derailleur doesn't seem to want to return fully even with the low stop wound all the way out. It can be gently persuaded to move the rest of the way by hand though.

Will replace cable just on general principles but am wondering if GRX derailleurs work better with full length outers...

Ta

 
Posted : 12/08/2020 9:57 am
Offline  thelooseone
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Got a GRX front mech on my Norco Search XR, which doesn't use a full length outer cable. Is the mech set up properly? I find it's sensitive to this, especially the cable tension. The dealer manual on the Shimano site has the set up procedure.

 
Posted : 12/08/2020 9:29 pm
Offline  13thfloormonk
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Yeah, that's what I keep asking myself but I've been through the setup step by step.

I recabled my road bike yesterday and setting up the Ultegra front mech was a peice of cake, and the GRX is exactly the same procedure. Weird.

 
Posted : 13/08/2020 7:22 am
Offline  rhayter
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This is very thorough and helpful:

 
Posted : 14/08/2020 1:01 pm
Offline  13thfloormonk
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That's a good video, thanks.

He uses a cable end cap where the cable first passes through the derailleur, which I think stops the cable rubbing directly against the derailleur body. I might try that as well.

Otherwise there's nothing he does that I'm not...

It actually works fine out of the stand, it's just in the stand it doesn't seem to move much when you make a trim shift. I'll just ride it a bit more, if it's OK on the trail then I'll leave it 🙂

 
Posted : 14/08/2020 1:46 pm
Offline  sillyoldman
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Not just a tiny bit too much cable tension?

 
Posted : 14/08/2020 8:04 pm

Offline  jonnyboi
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I had the exact same issue when fitting mine. It was down to having too much tension in the cable. I just backed everything off and started again being very careful to get everything lined up in the trim position. working perfectly now with ultegra shifters.

not running a full length outer either.

 
Posted : 02/09/2020 12:00 pm
Offline  13thfloormonk
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So mine is basically working perfectly on the trail, it was just in the stand that the 'trim' shifts didn't seem to be very slick and the mech barely appears to move when trimming. I backed off tension a tiny bit, not sure if it solved the trim issue but the shifting is fast and light so was probably a good adjustment.

Once I gave up fiddling and just started riding it I've not noticed an issue, certainly no rubbing in extreme gears, so I guess I was just getting hung up on nothing. I did give the mech a good clean and spray with GT85, perhaps expecting a mud-caked gravel mech to work as precisely as the Ultegra road mech on my summer road bike was a bit unrealistic...

 
Posted : 02/09/2020 12:13 pm

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