Can't find creak origin
12-21-23, 05:12 AM
#26
Senior Member
In pressfit applications grease acts as a oxidation barrier (which you want) but also removes friction (which you do not want). Since bicycle pressfit BB's are often more of a slip fit than actual press fit, the bearings can move in their shells due to pedaling forces. Grease does nothing to stop this and can actually add to it. Bearing movement in a pressfit shell means wear which makes the pressfit shell even more loose.
The loctite 600 series compounds act as oxidation barriers and they lock the bearings in place against the pressfit shell by A) glueing the bearing in place and B) filling voids between the bearing outer race and pressfit shell with a hard plastic compound.
When you use a bearing locking compound such as the loctite 600 series it's important to install the crankset before the compound sets so you get the bearing alignment as close the perfect as possible. Once the compound sets the bearings stay put really well.
12-21-23, 09:01 AM
#27
Senior Member
Thread Starter
Loctite 609, 640 or 641.
In pressfit applications grease acts as a oxidation barrier (which you want) but also removes friction (which you do not want). Since bicycle pressfit BB's are often more of a slip fit than actual press fit, the bearings can move in their shells due to pedaling forces. Grease does nothing to stop this and can actually add to it. Bearing movement in a pressfit shell means wear which makes the pressfit shell even more loose.
The loctite 600 series compounds act as oxidation barriers and they lock the bearings in place against the pressfit shell by A) glueing the bearing in place and B) filling voids between the bearing outer race and pressfit shell with a hard plastic compound.
When you use a bearing locking compound such as the loctite 600 series it's important to install the crankset before the compound sets so you get the bearing alignment as close the perfect as possible. Once the compound sets the bearings stay put really well.
In pressfit applications grease acts as a oxidation barrier (which you want) but also removes friction (which you do not want). Since bicycle pressfit BB's are often more of a slip fit than actual press fit, the bearings can move in their shells due to pedaling forces. Grease does nothing to stop this and can actually add to it. Bearing movement in a pressfit shell means wear which makes the pressfit shell even more loose.
The loctite 600 series compounds act as oxidation barriers and they lock the bearings in place against the pressfit shell by A) glueing the bearing in place and B) filling voids between the bearing outer race and pressfit shell with a hard plastic compound.
When you use a bearing locking compound such as the loctite 600 series it's important to install the crankset before the compound sets so you get the bearing alignment as close the perfect as possible. Once the compound sets the bearings stay put really well.
I've been greasing PF BBs for ages without issues though. I have never used retaining compound either (I thought that was only required when the BB was loose).
BTW, I found some rust stains on the crank spindle and on the outside of the DS bearing. After a close examination, they came from the preload wave washer that, for whatever reason, had some rust on it. As usual, I think Shimano's solutions are better engineered (breaking Ultegra cranks notwithstanding).
Last edited by Amt0571; 12-21-23 at 09:31 AM.
12-21-23, 12:58 PM
#28
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I always solved my crank creaking/ticking noise by by removing chain rings, slightly sanding mating chain ring and crank matting surfaces, greasing the surfaces, and torquing to spec.
Recently, I did this twice, but the creaking/ticking remained.
So, I removed the cranks and inspected the press fit brgs. NDS was rotating (by hand) completely smoothly. DS had an imperceptible drag. Crank would rotate completely freely.
I considered that the brgs did not need to be replaced. Assembled the crank, and the creaking-ticking re-appeared.
I then removed the crank a 2nd time, and replaced the brgs, and creaking/ticking disappeared.
I didn't expect the noise to be from the brgs since in the past it was always from the crank/bolt/chainring assembly.
Maybe the noise was slightly different, but I can't recall that detail.
Recently, I did this twice, but the creaking/ticking remained.
So, I removed the cranks and inspected the press fit brgs. NDS was rotating (by hand) completely smoothly. DS had an imperceptible drag. Crank would rotate completely freely.
I considered that the brgs did not need to be replaced. Assembled the crank, and the creaking-ticking re-appeared.
I then removed the crank a 2nd time, and replaced the brgs, and creaking/ticking disappeared.
I didn't expect the noise to be from the brgs since in the past it was always from the crank/bolt/chainring assembly.
Maybe the noise was slightly different, but I can't recall that detail.
12-21-23, 01:04 PM
#29
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Here is an int resting method.
Guy over in Austin had a creak no one could find. He tapped an old cell phone to different areas of his bike and set it to record sound when ridding. He was able to isolate a hair line crack at his seat tube water bottle cage. Go Figure...
Guy over in Austin had a creak no one could find. He tapped an old cell phone to different areas of his bike and set it to record sound when ridding. He was able to isolate a hair line crack at his seat tube water bottle cage. Go Figure...
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No matter where you're at... There you are... Δf:=f(1/2)-f(-1/2)
No matter where you're at... There you are... Δf:=f(1/2)-f(-1/2)
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12-29-23, 01:48 PM
#30
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My 5y/o road bike has started to creak sometimes. It seems more prone to do it when riding at night, so I suppose temperarture is a factor.
The creaking coincides with the crank movement and it also does it when standing up (so it's not a saddle issue). It creaks more when on the big chainring.
So far I've disassembled the cranks (Rival) and removed and reinstalled the bottom bracket. Bottom bracket is pressfit but has never creaked in 5 years. I regreased everything when I assembled it. I also disassembled the chainrings and greased the bolts. I have not removed the pedals (Shimano M520), but it creaks when pedalling using only one foot, either right or left, so they don't seem to be the cause either.
I have also greased the rear through axle and even the space between the RD hanger and the frame.
Finally, I've tightened the cassette and checked the freehub and everything seems alright. I have also checked the frame for cracks and found nothing. I also checked the wheels (Vision Team 35 disc) and they don't have cracks (I replaced the wheels the past summer because the old Mavic's had cracks on the spoke holes, which also caused creaks).
Any ideas? Am I missing something?
The creaking coincides with the crank movement and it also does it when standing up (so it's not a saddle issue). It creaks more when on the big chainring.
So far I've disassembled the cranks (Rival) and removed and reinstalled the bottom bracket. Bottom bracket is pressfit but has never creaked in 5 years. I regreased everything when I assembled it. I also disassembled the chainrings and greased the bolts. I have not removed the pedals (Shimano M520), but it creaks when pedalling using only one foot, either right or left, so they don't seem to be the cause either.
I have also greased the rear through axle and even the space between the RD hanger and the frame.
Finally, I've tightened the cassette and checked the freehub and everything seems alright. I have also checked the frame for cracks and found nothing. I also checked the wheels (Vision Team 35 disc) and they don't have cracks (I replaced the wheels the past summer because the old Mavic's had cracks on the spoke holes, which also caused creaks).
Any ideas? Am I missing something?
