Noisy hub after flight
Discussion
Strange one for me.
I packed up my bike to take it overseas with me and my very quiet Ultegra cassette/hub is now clicking away on freewheel when I've put the bike back together. Nothing has changed or been damaged that I can see and it all seems to shift through the gears normally, just noisy when it used to be silent.
Any thoughts? I preferred it silent.
I packed up my bike to take it overseas with me and my very quiet Ultegra cassette/hub is now clicking away on freewheel when I've put the bike back together. Nothing has changed or been damaged that I can see and it all seems to shift through the gears normally, just noisy when it used to be silent.
Any thoughts? I preferred it silent.
Starfighter said:
A rapid air pressure change will have forced the grease out even on a sealed hub. Not normally a problem but zero to 10000 feet in 4 minute is probably outside the design limits for the seals.
Hmmm was the bike in the back of Maverick’s Tomcat 🤣Aircraft holds are pressurised and it takes 15-25minutes to reach cruise altitude, the aircraft hold and cabin will be around 7000ft-8000ft depending on what plane you are on.
rs4al said:
Starfighter said:
A rapid air pressure change will have forced the grease out even on a sealed hub. Not normally a problem but zero to 10000 feet in 4 minute is probably outside the design limits for the seals.
Hmmm was the bike in the back of Maverick’s Tomcat ??Aircraft holds are pressurised and it takes 15-25minutes to reach cruise altitude, the aircraft hold and cabin will be around 7000ft-8000ft depending on what plane you are on.
gazza285 said:
What rapid air pressure change?
The 55-65% drop in pressure between ground level and aircraft cabin pressure at 8-10,000 depending on type. A typical airline gets to pressurisation hight in 3 to 4 minutes, maybe 5 on a heavy weight. That is quite rapid for a “sealed” hub designed to resist moisture ingress. Starfighter said:
gazza285 said:
What rapid air pressure change?
The 55-65% drop in pressure between ground level and aircraft cabin pressure at 8-10,000 depending on type. A typical airline gets to pressurisation hight in 3 to 4 minutes, maybe 5 on a heavy weight. That is quite rapid for a “sealed” hub designed to resist moisture ingress. If you cycled up a 6,000ft mountain or lived at 6000ft elevation as many do, you wouldn’t expect the grease to leak out from the hub.
Op which flight were you on, we can look on flight radar and see how rapid your hub pressure change was likely to be?
Edited by anonymous-user on Wednesday 4th November 12:23
Sounds like you’ve been upgraded. A quiet Shimano freehub to an excellently loud clicky Campagnolo freehub 
If you want to fix it, you’ll need to regrease the pawls in the freehub body. Rear wheel off, cassette off, freehub off, don’t drop anything or let anything fly off into the distance, generously regrease then reassemble. If in doubt consult YouTube. Good luck, though it’s not a difficult job really.
If you want to fix it, you’ll need to regrease the pawls in the freehub body. Rear wheel off, cassette off, freehub off, don’t drop anything or let anything fly off into the distance, generously regrease then reassemble. If in doubt consult YouTube. Good luck, though it’s not a difficult job really.
My MTB is noisy as hell so it was actually quite nice having some peace and quiet for a change
My LBS, where I bought the bike, suggested to strip/grease it and send them some pictures if needed and they'd see if they could spot anything. It seems to be smooth otherwise and nothing seems bent or out of line.
Unfortunately I'm in forced quarantine as part of the entry restrictions so I can't ride it till next week anyway.
My LBS, where I bought the bike, suggested to strip/grease it and send them some pictures if needed and they'd see if they could spot anything. It seems to be smooth otherwise and nothing seems bent or out of line.
Unfortunately I'm in forced quarantine as part of the entry restrictions so I can't ride it till next week anyway.
BlackWidow13 said:
Sounds like you’ve been upgraded. A quiet Shimano freehub to an excellently loud clicky Campagnolo freehub
If you want to fix it, you’ll need to regrease the pawls in the freehub body. Rear wheel off, cassette off, freehub off, don’t drop anything or let anything fly off into the distance, generously regrease then reassemble. If in doubt consult YouTube. Good luck, though it’s not a difficult job really.
How does one grease the pawls in a Shimano freehub? They are supplied as a non maintainable unit that bolts to the hub.If you want to fix it, you’ll need to regrease the pawls in the freehub body. Rear wheel off, cassette off, freehub off, don’t drop anything or let anything fly off into the distance, generously regrease then reassemble. If in doubt consult YouTube. Good luck, though it’s not a difficult job really.
El stovey said:
The op said he was on a 787 they’re pressurised to 6,000ft the pressurisation schedules is actually very gradual.
If you cycled up a 6,000ft mountain or lived at 6000ft elevation as many do, you wouldn’t expect the grease to leak out from the hub.
Op which flight were you on, we can look on flight radar and see how rapid your hub pressure change was likely to be?
I know many who like about 5000 feet and regularly cycle about 10000ft. The issue I am suggesting is the rate of change not the absolutes. A very slow climb will allow the “sealed” unit enough time to normalise with the change. A flight will see a faster pressure change and may be a cause. I don’t know. I am making a suggestion. If you cycled up a 6,000ft mountain or lived at 6000ft elevation as many do, you wouldn’t expect the grease to leak out from the hub.
Op which flight were you on, we can look on flight radar and see how rapid your hub pressure change was likely to be?
Edited by El stovey on Wednesday 4th November 12:23
Starfighter said:
I know many who like about 5000 feet and regularly cycle about 10000ft. The issue I am suggesting is the rate of change not the absolutes. A very slow climb will allow the “sealed” unit enough time to normalise with the change. A flight will see a faster pressure change and may be a cause. I don’t know. I am making a suggestion.
How much trapped air is there in a freehub? I doubt the volume of what little there is escaping as the pressures equalise would be enough to remove much grease from what is at best a barely sealed unit.Starfighter said:
The 55-65% drop in pressure between ground level and aircraft cabin pressure at 8-10,000 depending on type. A typical airline gets to pressurisation hight in 3 to 4 minutes, maybe 5 on a heavy weight. That is quite rapid for a “sealed” hub designed to resist moisture ingress.
Absolute balderdash.Op, just take your freehub apart and see if there is any grease left in it.
gazza285 said:
How does one grease the pawls in a Shimano freehub? They are supplied as a non maintainable unit that bolts to the hub.
https://www.parktool.com/blog/repair-help/freehub-serviceI have taken bikes on many trips and never had any issues due to hold pressure, sounds very unlikely to me.
Shimano freehubs aren't really serviceable. You're going to have to adjust the axle bearings and you'll probably damage the seals in the freehub, plus having to faff around and find an 11mm allen key or whatever crazy size it is.
The flight probably just coincided with the hub bedding in and the pawls on the ratchet loosening up.
My Dura Ace hub definitely makes a clicking noise, not as loud as some wheels I have but quite typical of a hub.
The flight probably just coincided with the hub bedding in and the pawls on the ratchet loosening up.
My Dura Ace hub definitely makes a clicking noise, not as loud as some wheels I have but quite typical of a hub.
ddom said:
gazza285 said:
How does one grease the pawls in a Shimano freehub? They are supplied as a non maintainable unit that bolts to the hub.
https://www.parktool.com/blog/repair-help/freehub-serviceI have taken bikes on many trips and never had any issues due to hold pressure, sounds very unlikely to me.
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