Drum braked rear hub for fixed gear

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SimonCelsa
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Drum braked rear hub for fixed gear

Postby SimonCelsa » 15 Jul 2020, 8:36pm

I realise a fixed rear hub can be braked by using leg power, but is anyone aware of any drum braked rear hub which is specifically designed for fixed gear use (not single speed).

There we go, short and sweet one sentence question. I can't see anything available after a quick google search which leads me to believe this may be a bl**dy stupid question but I can't fathom why.

Brucey
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Re: Drum braked rear hub for fixed gear

Postby Brucey » 15 Jul 2020, 8:54pm

niche market. Very niche market in fact, since you will (legally speaking) have twice as many 'brakes' on the rear wheel as is required.

If you want this functionality, I suggest that you use a fixed/free rear hub, fitted with a screw-on drum brake, such as a Kuwahara.

FWIW BITD when most hubshells were steel, SA 90mm brakes were made with the correct threading for a fixed sprocket (i.e. with a lockring thread). The logic here was that a steel thread would be strong enough for a freewheel (with a large sprocket fitted) even if it was about half the usual length, whereas this is less certain if the hubshell is aluminium. Fixed sprockets were often used on carrier bikes simply because they were more reliable than freewheels. So a steel hubshell could be made to do both jobs with no loss. Occasionally you will find one of these older hubs; I have only seen them in 40h format, with 'double' spoke holes on a small RH flange (a bit like old dynohubs).

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SimonCelsa
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Re: Drum braked rear hub for fixed gear

Postby SimonCelsa » 16 Jul 2020, 4:58pm

OK thanks for that Brucey. I was mulling over fitting a rear brake on my fixed commuter which is getting quite a bit of use at the moment. There are a few short, reasonably steep hills in the area and with gearing of about 67 inches I try and maintain a speed of below 22 mph with the front brake else my legs can't keep up. If the front brake went AWOL I would struggle to retard the speed with legs alone, perhaps I'll fit some decent pedal straps which should assist.

alexnharvey
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Re: Drum braked rear hub for fixed gear

Postby alexnharvey » 19 Jul 2020, 3:12pm

If you cannot brake the rear wheel sufficiently with your legs are you road legal without a second/third brake?

As a fellow fixed commuter it's a question I have been asking myself recently too, although I am clipped in to the pedals and I think I could stop the bike with my legs if I had to, although I prefer not to do all the braking with my legs and use the front brake too.

Jdsk
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Re: Drum braked rear hub for fixed gear

Postby Jdsk » 19 Jul 2020, 3:21pm

alexnharvey wrote:If you cannot brake the rear wheel sufficiently with your legs are you road legal without a second/third brake?

AFAICT the statutory requirement for each system is "efficient working order".
https://www.legislation.gov.uk/uksi/1983/1176/pdfs/uksi_19831176_en.pdf

Jonathan

thirdcrank
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Re: Drum braked rear hub for fixed gear

Postby thirdcrank » 19 Jul 2020, 3:30pm

Thread to needle, brakes have to be in efficient working order and, incidentally, the ability of the rider to operate them is not mentioned so tiny hands with big hoods are legally ok in this context.

A fixed-wheel is not a brake as such, but rather having one provides an exception from the requirement to have a rear brake. If push came to shove, then perhaps something like a fixed sprocket coming unscrewed through the lack of a lockring might be judged not to be fitted ie the regs might be interpreted as implying properly fitted.

Cyril Haearn
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Re: Drum braked rear hub for fixed gear

Postby Cyril Haearn » 19 Jul 2020, 3:35pm

I brake with my legs only, fixed and free
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seph
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Joined: 3 Sep 2010, 8:22pm

Re: Drum braked rear hub for fixed gear

Postby seph » 19 Jul 2020, 10:01pm

Interesting idea...
https://www.ebay.co.uk/itm/Sturmey-Arch ... 2f386dc70e
This has the brake, but is for single speed... How about spinning on a fixed cog and using an old bb lock ring to help keep it in place? As described here https://www.sheldonbrown.com/fixed-conversion.html

It’s not perfect, and though it is sometimes called a suicide hub(!) I think that’s only where people rely solely on leg braking, with no front brake, and then the cog unscrews :shock: .

I think it would be fine if you used the brakes to control the speed and kept the top run of chain tight...

seph
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Joined: 3 Sep 2010, 8:22pm

Re: Drum braked rear hub for fixed gear

Postby seph » 19 Jul 2020, 10:16pm

required.

If you want this functionality, I suggest that you use a fixed/free rear hub, fitted with a screw-on drum brake, such as a Kuwahara.


Karasawa https://www.sjscycles.co.uk/brakes/kara ... aces-arai/ Interesting...

Brucey
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Re: Drum braked rear hub for fixed gear

Postby Brucey » 19 Jul 2020, 10:34pm

oops.. :oops: ….. what is in a name, eh...?

:wink:

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mig
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Re: Drum braked rear hub for fixed gear

Postby mig » 19 Jul 2020, 11:21pm

Cyril Haearn wrote:I brake with my legs only, fixed and free


not sure i follow that. leg braking with a freewheel?

i trim a bit of speed off with by resisting with my legs but actually coming to a stop using leg braking isn't easy. okay if the rider is only at a low speed in a tiny gear then it's possible but coming to a stop from a regular road speed within a decent time and space is hard to do.

Cyril Haearn
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Re: Drum braked rear hub for fixed gear

Postby Cyril Haearn » 20 Jul 2020, 7:17am

mig wrote:
Cyril Haearn wrote:I brake with my legs only, fixed and free


not sure i follow that. leg braking with a freewheel?

i trim a bit of speed off with by resisting with my legs but actually coming to a stop using leg braking isn't easy. okay if the rider is only at a low speed in a tiny gear then it's possible but coming to a stop from a regular road speed within a decent time and space is hard to do.

Back-pedal brake
I have a front hand brake on fixed and freewheel bikes, hardly ever use it
Entertainer, juvenile, curmudgeon, PoB, 30120
Cycling-of course, but it is far better on a Gillott
We love safety cameras, we hate bullies