Bicycle Mechanics - Do Aluminum frames amplify subtle drivetrain noises inherently?

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I have always been able to set up the drivetrains on my steel road bikes to be nearly silent when the chain, cogs and chainrings are all clean and the chain is freshly lubed. This does not seem to be the case for my Flyte SRS-3 aluminum road bike. I have cleaned, adjusted and installed a top of the line PC-991 SRAM chain on my Flyte road bike. I am running Ultegra 6503 rear derailleur with an Ultegra 9 speed 12-23 cassette in the rear. In the front I have an Ultegra 6603 triple crank with a 6603 front derailleur. I try to avoid cross chain combinations but do end up running in the big ring and like the second smallest cog quite a bit which is the most creaky. The thing is, even in perfectly straight gear combinations I'm still getting some faint sideways grindy/creaky kind of noise. I'm beginning to think its nothing except the aluminum tubes in this frame picking up minute noises and amplifying them.
Could anyone share any personal experiences they might have on whether aluminum frames could possibly be responsible for exacerbating drivetrain noise? Thanks a bunch.
Steve530
05-25-12, 08:19 PM
Interesting.
I have two aluminum Klein bikes - a 1983 and a 2006. The 1983 has Campagnolo Record components and is completely silent. The 2006 bike has Campagnolo Centaur drive train with assorted components and it sometimes creaks and pops. I finally traced most of the creaking down to loose chainwheel bolts, but the noise sounds like it's coming from the fork or front wheel.
Maybe aluminum tubing is transmitting the noise better than steel tubing.
No, aluminum frames have similar sound amplifying or resonance effects as do steel frames. Just about the only frames with a reputation for amplifying drivetrain noise, are carbon fiber.
One thing you should be aware is that more modern chains and cassettes tend to be noisier than older stuff. That's the result of more aggressive shift gates which cause noise in a similar way to how trains are noisier as they go through switches in tracks.
Also more noisy are many of the newer freehub systems, but I assume you can tell the difference between freewheel ratchet noise and chain/sprocket noise.
If I may make a sincere offer, that sounds like a cheap plug for my own product, many people report that Chain-L works wonders in reducing drivetrain noise. You don't have to use Chain-L, but possibly changing your chain lube might solve your problem for little or no dollars.
oldskoolwrench
05-25-12, 09:08 PM
In my humble opinion, I think that different frame materials can sometimes amplify or resonate sound from something amiss. For example, the sound of a slightly loose headset when dropping the front wheel on the ground sounds different for a steel vs. aluminum vs. CF, in my mind at least.
That being said, other sounds that might be occurring in one location could be something completely different. Steve530's comment about a 'creak' and 'pop' sounding like loose chainring bolts but 'coming' from the front fork or wheel area is an example of the sound resonating through the frame. FWIW, from the fork or wheel area it could be something as simple as a Presta valve nut being slightly loose, to a front reflector resonating against the spokes, etc.
Those phantom sounds would drive me crazy when looking for them, but always gave me a sense of amazement when the culprit, however small, was found.
Like I said... just my 2¢.
I have some knowledge on sound deadening computers and the general consensus is that to quiet parts are quieter if they are enclosed.
I agree with FBinNY, that it's just the parts that are a lot louder. There's not much a tubular frame material will do to quiet down exposed mechanical parts. If anything, a heavier frame will reduce sound vibrations. Plastic, for the same given weight, dampen vibrations better than metals, but sheer mass does more to dampen than material choice.
oh, and for the record, the best way to quiet down wind buffet or drivetrain noise is to just use some ear plugs or muffs. But don't use them together, because then you will have a hard time hearing traffic around you.
oh, and for the record, the best way to quiet down wind buffet ....
so how fast are you riding??? Never found wind buffet noise to be an issue, but I must be operating well below the threshold where it's significant.
dscheidt
05-25-12, 10:36 PM
wind from certain relative directions can be really loud, even if you're not riding fast. I don't usually have a problem, but I have had a few rides in open country where it's painful. Headgear probably matters for that, too, since it can cause eddy currents around it.
My modern bike with an Alfine IGH is totally silent, until I touch the brakes, which squeal if used lightly. I sometimes get a bit creeped out by that, especially at night. Maybe I'll have to put a baseball card in the spokes.
No, aluminum frames have similar sound amplifying or resonance effects as do steel frames. Just about the only frames with a reputation for amplifying drivetrain noise, are carbon fiber.
One thing you should be aware is that more modern chains and cassettes tend to be noisier than older stuff. That's the result of more aggressive shift gates which cause noise in a similar way to how trains are noisier as they go through switches in tracks.
Also more noisy are many of the newer freehub systems, but I assume you can tell the difference between freewheel ratchet noise and chain/sprocket noise.
If I may make a sincere offer, that sounds like a cheap plug for my own product, many people report that Chain-L works wonders in reducing drivetrain noise. You don't have to use Chain-L, but possibly changing your chain lube might solve your problem for little or no dollars.
I'm beginning to believe that it may be a problem with the 10 speed crank on a 9 speed rear cassette. On paper it sounds so close that there should be no compatibility issue but I'm beginning to think that the very slight decrease in tooth thickness on the 10 speed compatible 6603 triple crank plays a role in this odd swooshing sound that I seem to be so annoyed by during rides. The new SRAM PC-991 chain seems to be the best one I have used yet and the potential seems to exist to analyze this noise further to get it mostly gone. I'll re-lube the chain before I ride again. I have about 150 miles on the factory lube and it hasn't rained yet during any of my rides with the new chain. Just out of curiosity, does anyone have a favorite 8/9 speed triple crankset that is still available new in 172.5 length at a reasonable price? The supply of the older 6503 Ultegra triple cranks seems to be drying up and even beat up used ones are starting to go up in price on ebay.
hueyhoolihan
05-26-12, 02:24 AM
i'm no physicist so i could be wrong on this, but i think that most materials, including aluminum, will dampen a vibration and hence a sound wave, somewhat unless some energy is put into it from some other source. OTOH some materials are more efficient in transmitting a vibration than others.
as has been mentioned, carbon fiber is very good at this, and as i have mentioned in a number of previous posts in other threads, my CF bike's drivetrain is driving me nuts with all the clatter. recently, i found that although i THOUGHT i had a good driveline, i didn't. i also found that on another bike, that the rear wheel cog was at an angle to the plane of the frame. that caused noise too.
i have found many causes for a noisy drivetrains, from mismatched, worn parts, to alignment, to faulty adjustment, but i doubt that it is inherent in aluminum frames. good luck. :thumb:
keep at it, i eventually found solutions to the vast majority of my noise problems. my most recent fix was discovering that my wipperman single speed chain's sideplates were riding on the ramped sides of my shimano hyperglide cog. fix was to use a surly single speed cog. funny, it was quiet as a mouse with a sram pc-1 single speed chain.
I'm beginning to believe that it may be a problem with the 10 speed crank on a 9 speed rear cassette. .... Just out of curiosity, does anyone have a favorite 8/9 speed triple crankset that is still available new in 172.5 length at a reasonable price? ....
Save your money for the moment. The only real difference between 10s and 9s cranks, is the chainring separation. That would only be a factor when riding an inner ring with the outer rear. The narrowness limits the available angle, before the chain brushes the outer chainring and the effect is easily identified.
I still think your problem is simple chain noise, which may be louder than what you're used to because of cassette sprocket cut, and differences in chin lube. In any case, you shouldn't spend dough replacing parts until you've confirmed that they are in fact the root cause of the problem.
so how fast are you riding??? Never found wind buffet noise to be an issue, but I must be operating well below the threshold where it's significant.
over 30km/h?
20km/h, it's not a big deal, but over 30km/h, then it gets somewhat annoying.
also, some helmets are louder than others.
over 30km/h?
20km/h, it's not a big deal, but over 30km/h, then it gets somewhat annoying.
also, some helmets are louder than others.
Please folks, don't hijack the thread. This isn't about wind noise. I think I know the difference. I was trying to get some suggestions on how to quiet my triple chainring 3 x 9 drivetrain on my Flyte SRS-3 aluminum frame road bike. My suspicion it that there are a few minor misalignments that are audible and the sound is being picked up somehow by the rear triangle. I'm going to work on it today and will post back here about any improvements I am able to achieve.
brian669
05-26-12, 12:02 PM
did you check your derailleur hanger?
i had an alum trek (1000sl maybe?) many years ago and i swapped out the ultegra 9sp triple crankset for a 10sp double and had absolutely zero issues. i doubt that's the problem unless you're running a short cage rear derailleur with your triple.
did you check your derailleur hanger?
i had an alum trek (1000sl maybe?) many years ago and i swapped out the ultegra 9sp triple crankset for a 10sp double and had absolutely zero issues. i doubt that's the problem unless you're running a short cage rear derailleur with your triple.
I'm definitely using the "GS" version of the Ultegra 6500 9 speed rear derailleur. My chain length seems to be about right too.
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