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File: maxresdefault (3).jpg (89 KB, 1280x720)
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https://www.youtube.com/watch?v=WWQ3iLVr-0E
>That cylinder is a mass dampener also known as a J dampener in physics.The purpose is to neutralize high frequency low amplitude oscillations.Mass dampeners are currently used in Moto GP and were banned in F1 in the mid 2000s.The mass dampener can also be placed on the fork,above the bottom bracket and as shown on the rear swing arm/triangle on a full suspension bike.
have these been used on road bikes yet? i have a stiff track bike fixie, anything that could improve performance or comfort would interest me. i haven't paid attention to bike stuff lately so idk if it has been mentioned on GCN/GMBN yet. GCN has done a lot of videos on tire pressure so i could see them experimenting with tuned mass dampers.
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>>2019204
There's no point in using a mass damper in a bike without a suspension, the damper itself would have to be too heavy to have any effect. The point of the damper implemented in the picture you posted is to keep the tire in contact with the road instead of bouncing on it, it's not to improve comfort. It improves performance by making the rear tire more stable in fast downhills, or on particularly rough level pathways, but it adds a weight penalty uphill.
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>>2019204
>dampener
>>2019221
>There's no point in using a mass damper in a bike without a suspension
yes but the human body technically suspends itself on a bike and acts like a mass damper
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>>2019221
nothing is totally rigid in reality, especially your fleshy body and padded cycling shorts, it's not 80kg (bike+rider) of true unsprung weight, the bike weighs 7kg and the carbon fork flexes
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you want the tire to make contact with the rough-ish road surface instead of bouncing off of it, both for rolling resistance, grip and reducing vibrations, so couldn't the mass damper help with that
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modern f1 cars have quite stiff suspension for aerodynamic reasons
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on my bike they went with thin seatstays as far as aluminium tubing goes, they are wide for lateral stiffness but narrow from the side view for vertical compliance
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my location is flat as a pancake so weight doesn't matter all that much. what you lose in acceleration you get back in momentum.
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on first world country asphalt roads the surface imperfections are tiny so maybe the mass damper wouldn't have to weigh a gorillion grams
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>>2019231
The mass advantage of a heavy bike's momentum in flatlandia is so understated. I pedal my 50lb cruiser like 3 times and it rolls until the next block
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>>2019234
True
In fact, the damper wouldn’t have to be at all
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>>2019226
If that were the case, having a suspension at all wouldn't make a difference, but the fact is that it does. The unpredictability of the way the rider applies his own body weight to the bike makes tuning a mass damper attached to a no suspension bike difficult, if not impossible.
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>>2019289
holy shit you people are brain rotted
>If that were the case, having a suspension at all wouldn't make a difference, but the fact is that it does.
MTB style suspension is considered undesirable on road bikes, but you have suspension in the form of pneumatic tires, frame/fork flex, handlebar flex, handlebar tape/cycling shorts/saddle cushioning
>The unpredictability of the way the rider applies his own body weight to the bike makes tuning a mass damper attached to a no suspension bike difficult, if not impossible.
it's incredibly consistent, you could tune it for steady state seated pedaling on smooth asphalt at 30-40km/h or whatever

>>2019265
cope. GCN makes a gorillion videos about how the optimal tire pressure should be lower than you think and lower than continental's minimum pressure rating for their gp 5000 tires. so there is clearly room for improvement. someone could at least experiment with it instead of being dogmatic about it being useless.
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>If that were the case, having a suspension at all wouldn't make a difference, but the fact is that it does.
and my point is that a well-designed tuned mass damper might make a difference for fuck's sake
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formula 1 and motogp are on asphalt, formula 1 cars would probably use them if they were legal, motogp use them, you people are retarded to not see any similarity between a formula 1 car with stiff suspension or a motogp motorcycle and a road racing bicycle
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or you could tune for riding over cobblestones, like how f1 cars would want to cut corners going over the kerbs
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Or you could just ride a steel frame like God intended.
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>>2019340
the use of technology and tools is one of the defining features of humanity, it's pretty freaking awesome how much you can improve your quality of life with numerous things outside of cycling as well if you can keep your physical and mental health in check, clean up your desk etc so you don't get stuck in one of the slowest boards on 4channel for years looking at pictures of bicycles and posting repetitive cope shit like "steel is real"
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like how you're still using walmart inner tubes because sheldon brown saying that reputable brand butyl tubes are significantly higher quality didn't register in your brain, you didn't adopt TPU inner tubes even as prices came down because you didn't understand the advantages, because your unhealthy boomer lifestyle has lead to a horrific cognitive decline, society is just waiting for you to die at this point
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>>2019354
You're trying to solve an issue you created in the first place by not riding steel.
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>>2019378
steel bikes are measurably slower, you're just coping, it's about making improvements to something that is already good as fuck, not fixing something that's broken
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>>2019380
So are heavier bikes.
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>>2019204
We're entering compound bow archery levels of autism.
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>>2019396
>>2019204
You mean old school citroen levels of suspension autism.

https://youtu.be/j7pFxgDmZXQ?t=259
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>>2019381
not if the added weight is useful, like on aero bikes. to get the lowest rolling resistance you want to get rid of vibrations, hence the shilling for wider tires and lower tire pressure, it's pretty obvious that mass dampers could help with that. the improved grip could also help with cornering fast with confidence and riding in wet conditions. improved ride quality is another benefit of mass dampers which could reduce rider fatigue on longer rides.
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>>2019380
>measurably
Are they now? How much slower will a steel bike be than a carbon one on a flat 100 km loop with identical power input?
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>>2019519
https://www.youtube.com/watch?v=XE_GKePa3CQ
this was with the same wheels and the same position and they got 50 secs over 40km
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>>2019571
That's not riding though, it only measures one aspect, wind resistance.
If you put a dampener on your bike it will also be measurably slower in this test.
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>The purpose is to neutralize high frequency low amplitude oscillations

but how, and why?
the human body is a gigantic mass damper, gotta think in terms of physics this little guy is going to do the % of work it weighs against the human body. so like if it weighs 250 grams or half a pound, on a 150lb rider 0.33%?

it's also not connected in series with any spring so what the hell is it dampening?
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>>2019204
Everybody at MSA has jumped on the hype train lmao.
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>>2021430
Picture explains how it works for a building, but it works the same on the suspension by replacing the pendulum with a spring. Basically the suspended mass vibrates at the same speed as the mass it's attached to, but with enough delay to be out of phase. The vibration energy of the large mass is being damped by the relative displacement between it and the suspended mass.

https://www.youtube.com/watch?v=lhNjfNUOUo8

The reason it's being considered alongside regular dampers is because there's too much unsprung mass relative to the total mass of the bicycle for a bike suspension to be able to absorb road irregularities without bouncing all over the place. It also has the plus side of being tunable for the specific frequency at which the tires bounce, while a regular spring + damper works more like a low pass filter.

The human body can work as a mass damper if the rider contracts and extends the legs at just the right time to counteract the oscillation, but that's impossible for frequencies higher than 1 hz or so, far below the response of the tires.
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tuned mass damper is such a pseud tier goal, what we need is an active mass amplifier to increase cornering agility, not slow it down with damping
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https://www.reddit.com/r/london/comments/1gk2m7m/comment/lvi5vuv/
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Unlesss I’m mistaken wasn’t Time’s “Aktiv” fork based on this principle?
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>>2024136
that's awesome, i didn't know that. maybe some autist could experiment with this type of thing and turn it into a product that can be attached to any bike.

>Specially designed by TIME using proven vibration reduction engineering techniques similar to those used in F1 and automotive designs, the AKTIV Fork conceals an innovative tuned mass damper that neutralizes a measure of road noise before it travels to your hands and arms.

>Vibrations between 25 and 50Hz – such as those felt on rough chip seal pavement – cause a corresponding counter-movement of the small weight concealed inside the fork leg that cancels some of the input.

>Unlike polymer inserts or springs, AKTIV does not interfere with the bike’s handling or cause a vague feeling at the bars. AKTIV is incredibly light and sleek, providing real anti-fatigue benefits with a minimal weight penalty. It’s easy to see how even this small increase in comfort aboard your TIME can lead to a better experience on the road.

https://www.youtube.com/watch?v=YNH9CBEOrMU
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>>2019230
That’s a track bike literally designed to be a dummy stiff as humanly possible
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>>2024181
I have a TIME bike with an Aktiv fork. Noticeably smoother on fast descents than my older bikes. Smoother ride over long hours comfort wise. Despite living in a western european country roads are still awful sometimes, ridden with cracks, bumps, non uniform asphalt. Think it only adds up 400 to 500g more weight, so basically the weight of disk brakes
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>>2019230
>laterally stiff vertically compliant meme
>on a fucking alu frame of all things



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