
Hi all,
I got my Giant Revolt 1 (GRX40O) from an official national distributor/dealer a few days ago.
At delivery, there were already some issues with the bike. I brought it to the dealer and they fixed most.
Except for this grinding sound that I hear when the cassette is at higher gears. The mechanic tried to fix it once. He mentioned that it's a chain tension issue. I rode the bike back and didn't hear the sound.
The next day I brought it on a 30km ride. Am hearing the sound across all gears in the cassette. In fact the sound is noisier and I can feel a bit of the grinding on the wheel set.
I contacted the dealer and they didn't reply to me yet.
There are lemon laws in my country allowing me to exchange etc. if there is a defect.
My question is, is this a small tuning issue or appears to suggest a defect in the group set?
Help needed for strange sounds from my Brand New Revolt 1
byu/Giantstoneball ingravelcycling
by Giantstoneball
6 Comments
It sounds like the chain is rubbing the front derailleur.
Should be an easy adjustment.
I’ve never used GRX, so someone else will have to chime in…but on a couple Shimano road groupsets I’ve used there is a “trim” function where the lever actually has more positions than just one for each chainring. It allows the derailleur to be moved just a tad to prevent rubbing like this.
[deleted]
If it’s new you might be able to get your bike shop to adjust it for you. For everything else there’s ~~MasterCard~~ *Park Tool repair videos on YouTube*. I swear everything I know about bikes is thanks to that Calvin Jones guy.
In your case check out this one on [front derailleur adjustment](https://youtu.be/ZNG7g83lI-s?si=HUXdWshNYYzJBpAX)
Is the chain installed correctly?
Chain rub.
Either trim your chain position or slightly adjust your FD yourself. Its 30sec job
Chain rub! I had that issue, apparently Giant didn’t double check the chain line difference between a Tiagra vs GRX FD, they just slapped on that Tiagra FD just cause its a 10 speed FD and saved some bucks vs using a proper GRX front derailleur. Immediately replaced my FD with a GRX variant and saved some headaches from my local mechanics. Good luck!