What makes a pawl h...
 

What makes a pawl hub louder or quieter?

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In a recent thread about the quietest hub available, the Newmen Fade had a couple of mentions. This got me thinking what, aside from the lubrication used, makes different hubs quieter or louder than others. This is a bit of a monologue of what I've thought so far.

The sound comes from pawls snapping back into the ratchet ring. For more noise, we want more and bigger hits.

More points of engagement means more hits events per revolution, and more pawls means more hits at each point.
Newmen Fade - 108 total hits per revolution (36poe, 3 pawls)
Hope Pro 4 - 176 (44poe, 4 pawls)
Hope Pro 5 - 324 (108poe, 3 of 6 offset pawls engage at each point)
Hope Pro 5 E - 324 (54poe, all 6 pawls engage at each point)

Now onto making each click louder. We need to maximise the kinetic energy of each pawl snapping into the ratchet ring. Stronger return springs would allow more energy to captured. Nukeproof does offer aftermarket quieter (thinner) springs for some of their hubs. I guess the depth and tooth angle of the ratchet might also have an effect, as might pawl tip shape and material - but I can't think why.

Any other reasons?


 
Posted : 13/07/2023 12:22 am
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Resonance. (Hub shape and volume)

Materials.

Some frames also exacerbate the noise as they resonate too.


 
Posted : 13/07/2023 12:36 am
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+ the size of the ratchet ramps / drop from top to bottom (further to spring rhe pawl downwards, more force stored into each spring at the top of each ramp, to hammer the pawl into the ratchet harder)


 
Posted : 13/07/2023 12:43 am
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+ how thick or thin (and percentage fill) of the oil/grease.


 
Posted : 13/07/2023 1:25 am
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Real men ride with LOUD hubs, init.


 
Posted : 13/07/2023 3:52 am
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Would those berd stringy spokes sound any different?


 
Posted : 13/07/2023 8:54 am
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more force stored into each spring at the top of each ramp, to hammer the pawl into the ratchet harder)

Lots of hubs don't have per-pawl springs, they have a single circular spring which passes through all the pawls.

Here's one I dismantled earlier:

[url= https://live.staticflickr.com/65535/53041929307_9ef78bce59_o.jp g" target="_blank">https://live.staticflickr.com/65535/53041929307_9ef78bce59_o.jp g"/> [/img][/url][url= https://flic.kr/p/2oP8KCx ]Hub[/url] by [url= https://www.flickr.com/photos/brf/ ]Ben Freeman[/url], on Flickr

The spring is the tiny metal band with a hook in one end.


 
Posted : 13/07/2023 10:09 am
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+ the size of the ratchet ramps / drop from top to bottom (further to spring rhe pawl downwards, more force stored into each spring at the top of each ramp, to hammer the pawl into the ratchet harder)

I wouldn't think the distance would make a difference - a short hard spring can hold the same energy as a longer but softer one.

Would those berd stringy spokes sound any different?

I expect it would affect how the sound resonates. Not having a tyre on the rim (like some hub sound videos I've seen) would too.

Lots of hubs don’t have per-pawl springs, they have a single circular spring which passes through all the pawls.

That's the design the Newmen Fade uses too. It doesn't look like a design that can apply much force on the pawls, must just be pushing a bit at the far end of the their bases. I wonder if the single spring also helps reduce noise through the link it creates between all the pawls.

Project 321 use magnets instead of springs, and offer two pawl options with different shapes, weight, and magnet. Why would a multi-toothed pawl make it noisier?


 
Posted : 13/07/2023 7:39 pm