"Woo woo woo" sound going downhill at high speed
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"Woo woo woo" sound going downhill at high speed
Greetings Ladies and Gents,
Hearing and slightly feeling a sound I can only describe as a low-pitched, repeating 'Woo' at high speed descent. I "feel" like it is coming from the rear of the bike. Is it my rear bearing? I've given it all a once over on the bike stand, brakes, frame, all looks solid. I cannot replicate the sound on the stand spinning the pedals. I have never heard this sound climbing or on the flats.
Everything was replaced before I got injured a few months ago and I am just getting back on the bike. Definitely don't want anything catastrophic happening.
I've got a new KMC X10SL DLC chain, a new SRAM PG1070 10-speed cassette, and a Novatec AS511SB/FS522SB hub back there.
Let me know your thoughts!
Hearing and slightly feeling a sound I can only describe as a low-pitched, repeating 'Woo' at high speed descent. I "feel" like it is coming from the rear of the bike. Is it my rear bearing? I've given it all a once over on the bike stand, brakes, frame, all looks solid. I cannot replicate the sound on the stand spinning the pedals. I have never heard this sound climbing or on the flats.
Everything was replaced before I got injured a few months ago and I am just getting back on the bike. Definitely don't want anything catastrophic happening.
I've got a new KMC X10SL DLC chain, a new SRAM PG1070 10-speed cassette, and a Novatec AS511SB/FS522SB hub back there.
Let me know your thoughts!
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#3
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Might be worthwhile if you have a riding partner or club to ask someone alongside you to see if they hear anything. Could be wind noise? Have you serviced the hubs? It seems you mention having a new hub on the rear? Was it checked to be sure it was lubricated and tensioned properly?
Have you any other accy on the bike, like a bag, pack, etc. that might have a strap howling?
Have you any other accy on the bike, like a bag, pack, etc. that might have a strap howling?
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The ex-GF's dog used to make that sound:
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Brake pad rub due to something out of round?
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My bikes makes all sorts of different noises at different times. If you aren't having an issue, then it might not be anything. I make a lot of different noises too. Sometimes a big grunt or yell as a I top a hill makes it seem all the more faster.
If you are coasting and your woo woo woo is an rrrrh rrrrh rrrrh instead, then I'd say it's just your free hub pawls. Some freehubs both the quiet ones and the noisy ones make very unique sound when coasting at a high speed.
If you are coasting and your woo woo woo is an rrrrh rrrrh rrrrh instead, then I'd say it's just your free hub pawls. Some freehubs both the quiet ones and the noisy ones make very unique sound when coasting at a high speed.
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I think I may know what it is!

No, sorry, that was a "Weee weee weee" noise.
Seriously, though, it is almost impossible for anyone on a forum to diagnose a noise, especially one you cannot duplicate on a repair stand. Sometimes it's a matter of swapping a compatible rear wheel with someone to eliminate hubs, tires, freewheel, etc. If you're not pedaling during your descent, you can eliminate chain, crankset, or RD jockey wheels.

No, sorry, that was a "Weee weee weee" noise.
Seriously, though, it is almost impossible for anyone on a forum to diagnose a noise, especially one you cannot duplicate on a repair stand. Sometimes it's a matter of swapping a compatible rear wheel with someone to eliminate hubs, tires, freewheel, etc. If you're not pedaling during your descent, you can eliminate chain, crankset, or RD jockey wheels.
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