Winfried

Hello

I have a couple of questions:

1. What makes that sound when the wheel is spinning? The freewheel for the two-sprocket derailleur or the IGH?
2. Can something be done to make it more quiet? I'm used to the Alfine 11 and find the sound of regular bikes like the Brompton annoying

Thank you.

pastorbobnlnh 

The primary noise you are hearing is the internal noise of the Shimano Alfine hub. Other then to make certain it has the correct amount of oil (which might quiet it slightly), there is really nothing you can do to change the noise. I'm guessing you are hearing primarily the pawls as they slide past their notches when you stop pedaling and coast.

Any sound coming from tension arm and the jockey wheel and pulley is minimal and secondary. You could remove these and grease the bearings.

Winfried

Thanks for the info. You mean the BWR :-)

It's only six months old, and it's been sounding like that since I bought it new, so it looks like it's the normal noise by a Brompton.

I'll give a try. Thanks.

pastorbobnlnh 

My guess exactly, that the Alfine is new--- and it just is noisy--- now--- and always will be.

BWR? Not certain what that means. Tried googling it but nothing came up that made sense in this context.

Winfried

BWR is Brompton's IGH.
https://chestercycling.wordpress.com...range-bwr-hub/

The Alfine is very silent… and sitting on my non-folding bike. I was mentioning this because it's very quiet while regular bikes, and that includes Brompton, are much noisier, which is why I asked the question.

Answer so far: It's normal and nothing can be done about it.

fietsbob

3 by 2 cog BWR is for wide range (.064/1/1.57) the BSR is Standard range the same ratios as the AW3 has long been.. (.75/1/1.33)

a Broken in 20+ year old AW3 is pretty quiet if kept oiled occasionally..



I mainly hear the chain passing over the tensioner pulleys , even on my relatively New M3L

softer Nylon Plastic Tacx Pulley is quieter than the original Sun Race pulley ,

But is N/A on a BWR 6 speed
because the Pulleys are unique to Brompton for their Shifter design..
the plastic self lubricates on the smooth pin which it spins and has to move sideways .( No Bearings at all )

The custom ones seen out of SEA, with a sealed bearing made in Aluminum metal would be Louder.. it's all relative ..

I've seen some of those fish scale patterned cobbled streets in central Paris .
ride those and the louder surface under the tires will Mask the other noises you cannot reduce.

smallwheeler

the sound you hear is the passive ticking of the pawls when they are not engaged. the alfine hubs use a roller clutch mechanism.

true story:

i have a friend with a townie bike fitted with an alfine 11 hub. i asked him how it was working out. he replied, "the hub works great, but i miss the sound of the ticking pawls. for me, that clicking noise = freedom."

one man's annoyance is another man's freedom? (no doubt, literally, in some instances..)

my advice: embrace the sound of freedom.

tik-tik-tik-tik-tik-tik-tik-tik-tik-tik-tik...

Winfried

Thanks much for the infos about pawls vs. roller clutch:
https://pardo.net/bike/pic/mobi/d.winners-hub/index.html

I definitely prefer silent bikes. Too bad there's no way to make the 6-speed Brompton as quiet.

fietsbob

Wonder if there is a roller clutch freehub on the hubs on Police Special Mountain bikes for the 'sneak Up on them advantage'?

Winfried

That's what I wondered too, because it's pretty cool to be able to ride by pedestrians unnoticed

A video that explains how a roller clutch works, and why it's more silent than the traditional pawls + ratchets solution:
#t=0m34s

smallwheeler

there's always this option (which takes a bit fearlessness, i.e., courage plus ignorance and/or €€€):

brompton alfine 11

Winfried

Right, but it's heavy and on the expensive side. Too bad no one's come up with a lighter six-speed IGH so that Brompton could replace their 2x3 unusual solution.

chagzuki

Converting the hub to oil or regreasing it can make it smoother and quieter.

dynaryder

Sorry smallwheeler,but I gotta say it. That's a sloppy cable routing. That thing has to hit when you fold the bike. Plus I could see the adjuster fouling with something when folding. Looks like they cold set a stock triangle;this is a good example of why they should've used an aftermarket purpose-built triangle.

Winfried

For those with deep pockets + wish for a better IGH…

Kinetics ? Recumbents, Folding Bikes, Custom Bicycles | Brompton

fietsbob

the Glasgow Scottish shop owner posts in Frame builders section, Here, has custom Made forks and rear sections for a Rohloff DiscBrake bike build.


May be an advantage to buying the Ti X version for the parts that will be removed , since reselling the Titanium parts replaced will get you good Money.