Jammed R Shimano Grx lever

[Gearoidmuar]

Bike has done 3000m. A few months. Stopped and dropped chain onto smallest sprocket. STI seized. Will not move enough to click and push chain inwards. What's likely cause? Can see nothing useful under hood

[colin54]

I'm assuming the R in your title stands for rear derailleur. Have you tried disconnecting the cable from the derailleur and seeing if it shifts/indexes correctly & freely without the RD attached ?
It's possibly worth removing the cable to make sure it's not kinked and is running smoothly over the bottom bracket & through the frame (if it's internally routed), it may just be a broken strand inside the lever (unlikely at such a low mileage). The normal first fix is spray some lube into the lever internals in case the grease inside has gone solid and is stopping the pawls working correctly, again unlikely considering the newness.
Any chance of a warranty replacement if it's still fairly new and indeed turns out to be the shifter ?
This thread may get some more answers if you move it to the technical section of the forum
Good luck.

[Gearoidmuar]

Thanks Colin. R was for Right, but rear as well. I'm going to tackle it today! I was 30m from home and managed to get home using the 30x11 or for small bits, the 46x11 and about 400 yds of walking on steeper pitches. They were the only available gears to me. It's a gravel bike. I could've screwed the chain into another cog but it was a roasting hot day (27C). I moved up the hood when I got home and couldn't see anything amiss, but I must get off the cover and see what's going on. It has internal cabling...
I thought that my legs would feel battered today, but not at all!

[colin54]

I just did a google for 'Shimano GRX shifter problem' and came up with this one first, it might be worth looking through the rest as well for some more ideas.
https://singletrackworld.com/forum/topi ... ter-issue/
EDIT
There are some pictures linked in the last post on this thread which may help.
https://forum.earlyretirementextreme.co ... hp?t=11466
(early retirement extreme website...whatever next !).
If you are still having problems, if you enter the exact model number into the Shimano Tech doc site and have a look in the dealer manual, there is set of initial set up instructions which may be of use, you may possibly have received a copy with the bike.
For example :- https://si.shimano.com/api/publish/stor ... 04-ENG.pdf
This one's for hydraulic braked GRX, gear set-up is towards the end of the document.
Again, good luck.

[Gearoidmuar]

I just did a google for 'Shimano GRX shifter problem' and came up with this one first, it might be worth looking through the rest as well for some more ideas.
https://singletrackworld.com/forum/topi ... ter-issue/
EDIT
There are some pictures linked in the last post on this thread which may help.
https://forum.earlyretirementextreme.co ... hp?t=11466
(early retirement extreme website...whatever next !).
If you are still having problems, if you enter the exact model number into the Shimano Tech doc site and have a look in the dealer manual, there is set of initial set up instructions which may be of use, you may possibly have received a copy with the bike.
For example :- https://si.shimano.com/api/publish/stor ... 04-ENG.pdf
This one's for hydraulic braked GRX, gear set-up is towards the end of the document.
Again, good luck.

Exact same as the end of the first link. It could have been caused by me going down down down without cycling when I stopped. Anyway bike mechanic who's a genius as seen this before and he said cable had some fancy coating which makes it marginally thicker and that this isn't a good idea.
Another thing. I couldn't open front thru axle before going to bike shop. Apparently fused. He got this to free with some heat from a small blow torch.
His advice...Use anti-seize grease on thru axles. Otherwise they're a b***s.

[colin54]

Glad you got it sorted.