The bike is a TREK Superfly hardtail in Carbon with 10x Sram XX. I have been trying to find the source of the creak for a very long time. I took it to a LBS who could not solve the issue for me either. I am a relatively experienced home mechanic. I can do most things such as change BBs, bleed brakes, true a wheel and so on.
The creaking comes when putting down power and seated only. Anything less than around 200w and nothing is heard. As soon as I start climbing, the creak comes. If I get out of the seat and pedal, nothing is heard. I suspect the quick release may be the issue. I changed this and the sound disappeared for an hour but then came back. There is no thru-axel on the back of this frame.
Here is what I have done so far without success:
1. Changed BB. It needed it anyway, and so it eliminated a problem just in case.
2. Took out the pedals from the crank, regreased and reinserted.
3. Lubed the pedals themselves (Shimano SPD).
4. Took out the seat post and put carbon paste instead of anti sieze or grease.
5. Took off the derailleur, re-lubed the threads into the hanger and put it back.
6. Needed a fork service, so even though it was not that, it’s eliminated.
7. Checked wheels for problems with axel – nothing.
8. Checked brake calipers.
As the creak only comes when the rear triangle is weighted, could it be something with movement in the QR causes it moves against the frame? Is there a type of QR I am not considering?
Thanks for any help. The mystery is causing me to lose sleep. I creak in my dreams.
MinimalMojo on
Check saddle:
– connection of rails to seat post – common to have a bit of dirt in there – need to clean and lightly grease before reassembly
– if above doesn’t fix, then also check where saddle rails terminate at the saddle base itself – I’ve had numerous saddles where there was a creak where they met, and the temp fix was a bit of lube squeezed in there, but ultimately I had to change the saddle because it kept coming back
Soup6029 on
A friend I ride a lot with had this issue with 2 carbon frames. There is a special paste for carbon fiber frames. He put it on the seat tube and it stopped.
Sorry, I don’t know what it is called.
dannylills8 on
Saddle rails try a different saddle see if it goes
MongooseHelltopper91 on
Check bottle cage mounts and ensure your spokes are setup properly, not too loose/tight. I’ve heard horror stories about both of those being the problem for creaks.
Zestyclose_Pace8201 on
Check if derailleur hanger is fully tightened.
mrlacie on
I had a similar issue and it was the seat post slightly ticking against the seat tube. I would assume what you did in #4 would help, but who knows.
molokkofreak on
try to remove/unscrew derailer/ axle hangers from the frame, a common place for sand and mud causing creaks
VastAmoeba on
I would check your chainrings also. Just take them off, clean them and reinstall with some grease. Also, try an entirely new seatpost, seat post clamp and saddle if you have a spare lying around.
Install the post with carbon assembly paste instead of grease.
But really it is a process of elimination now, so you have install each component and test, one at a time until you find it.
With it only being seated though I would focus on the seat/seat tube/saddle junction.
blumpkins_ahoy on
Check your rear spokes at the intersection to see if they’re notched.
Plantemanden on
Unrelated to the creak: Your rear tire should really be your front, and vice versa.
11 Comments
The bike is a TREK Superfly hardtail in Carbon with 10x Sram XX. I have been trying to find the source of the creak for a very long time. I took it to a LBS who could not solve the issue for me either. I am a relatively experienced home mechanic. I can do most things such as change BBs, bleed brakes, true a wheel and so on.
The creaking comes when putting down power and seated only. Anything less than around 200w and nothing is heard. As soon as I start climbing, the creak comes. If I get out of the seat and pedal, nothing is heard. I suspect the quick release may be the issue. I changed this and the sound disappeared for an hour but then came back. There is no thru-axel on the back of this frame.
Here is what I have done so far without success:
1. Changed BB. It needed it anyway, and so it eliminated a problem just in case.
2. Took out the pedals from the crank, regreased and reinserted.
3. Lubed the pedals themselves (Shimano SPD).
4. Took out the seat post and put carbon paste instead of anti sieze or grease.
5. Took off the derailleur, re-lubed the threads into the hanger and put it back.
6. Needed a fork service, so even though it was not that, it’s eliminated.
7. Checked wheels for problems with axel – nothing.
8. Checked brake calipers.
As the creak only comes when the rear triangle is weighted, could it be something with movement in the QR causes it moves against the frame? Is there a type of QR I am not considering?
Thanks for any help. The mystery is causing me to lose sleep. I creak in my dreams.
Check saddle:
– connection of rails to seat post – common to have a bit of dirt in there – need to clean and lightly grease before reassembly
– if above doesn’t fix, then also check where saddle rails terminate at the saddle base itself – I’ve had numerous saddles where there was a creak where they met, and the temp fix was a bit of lube squeezed in there, but ultimately I had to change the saddle because it kept coming back
A friend I ride a lot with had this issue with 2 carbon frames. There is a special paste for carbon fiber frames. He put it on the seat tube and it stopped.
Sorry, I don’t know what it is called.
Saddle rails try a different saddle see if it goes
Check bottle cage mounts and ensure your spokes are setup properly, not too loose/tight. I’ve heard horror stories about both of those being the problem for creaks.
Check if derailleur hanger is fully tightened.
I had a similar issue and it was the seat post slightly ticking against the seat tube. I would assume what you did in #4 would help, but who knows.
try to remove/unscrew derailer/ axle hangers from the frame, a common place for sand and mud causing creaks
I would check your chainrings also. Just take them off, clean them and reinstall with some grease. Also, try an entirely new seatpost, seat post clamp and saddle if you have a spare lying around.
Install the post with carbon assembly paste instead of grease.
But really it is a process of elimination now, so you have install each component and test, one at a time until you find it.
With it only being seated though I would focus on the seat/seat tube/saddle junction.
Check your rear spokes at the intersection to see if they’re notched.
Unrelated to the creak: Your rear tire should really be your front, and vice versa.