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-   -   Shimano Alfine 8 speed hub on a Brompton? (http://www.bikeforums.net/folding-bikes/455702-shimano-alfine-8-speed-hub-brompton.html)

mulleady 08-18-08 05:17 PM

Shimano Alfine 8 speed hub on a Brompton?
 
I've tried the Alfine hub on the Cadenza 08 and it really is a beautiful shift. For me this is a realistic alternative to adding a Rohloff hub which would be OTT for the Brompton.

Now I know that people have successfully fitted Rohloff, Sturmey Archer and Shimano Nexus 8 speed hubs to the Brompton. The Alfine is listed below:

http://www.ultimatepursuits.co.uk/pr...=1&v=VARSGS500

The only challenge seems to be the OLD measurement is 135mm compared to less on the others such as 131mm for the Rohloff and 124mm for the SA X-RF8 . Would this problem be surmountable?

LittlePixel 08-18-08 05:32 PM

Yes if you get a wider rear triangle fabricated by a certain Mr S. Parry..
h

greenbrompton 08-18-08 06:55 PM

sturmey archer 8 speed hub at kinetics

porschetoyz 08-18-08 07:15 PM

kinetics?

greenbrompton 08-18-08 07:49 PM

www.kinetics.org.uk/html/brompton.shtml He has some pictures on flickr if you search 8 speed brompton. Ben Cooper, he is a nice guy.

somnatash 08-18-08 11:13 PM

Quote:

Originally Posted by mulleady (Post 7297701)
The only challenge seems to be the OLD measurement is 135mm compared to less on the others such as 131mm for the Rohloff and 124mm for the SA X-RF8 . Would this problem be surmountable?

Hi :)
Juliane has mounted the 8Spd shimano nexus to bromptons which is OLD 132mm. She is cold widening the triangle with special tools, a new rear is not necessary in that case. So 3mm more for the Alfine...should be possible, no? But I don't know for sure. I have just send her an email on a different matter and added your question. If you like to ask her yourself:
http://www.junik-hpv.de/html/kontakt.htm

somnatash 08-18-08 11:22 PM

Quote:

Originally Posted by greenbrompton (Post 7298653)
Ben Cooper, he is a nice guy.

That is certainly true, the bike shop a real treasure box and Ben is very friendly - nothing "nose up" there. Perhaps you only might need a certain amount of patience and trust when dealing with him.

mulleady 08-19-08 01:49 AM

Kinetics and Ben?

Sure he's a nice guy and very skilled at what he does but he also takes ages to do some jobs. Ages can amount from weeks to months. I am basing this on 2 cases I know of personally rather than my own.

I'm sure some people had better experiences.

mulleady 08-19-08 02:57 AM

Usef ul review of Alfine hub here:
http://www.bikemagic.com/news/article.asp?UAN=6400&v=1

LittlePixel 08-19-08 04:48 AM

Could extra width be added by a clever welder/brazer by removing, filleting and re-attaching the dropouts those few crucial millimetres outwards? Actually a bit of deft double bending on the dropouts could also do it without having to affect the triangle geometry?

mulleady 08-19-08 05:13 AM

Quote:

Originally Posted by LittlePixel (Post 7300538)
Could extra width be added by a clever welder/brazer by removing, filleting and re-attaching the dropouts those few crucial millimetres outwards? Actually a bit of deft double bending on the dropouts could also do it without having to affect the triangle geometry?

On 2nd thoughts the Nexus Premium hub offers a slightly higher gear at 87" as opposed to the Alfine's 80". Could I alter this upwards by using a different rear cassette.

Hope you cna join evilV, Sesamecrunch and some of us at Hyde Park this weekend LP, would be great to see you!

euhmoins 02-04-09 09:09 AM

Hi,

Ok this thread is bit old, but I'd like to ask you the following anyway.
I also wish to upgrade my Brompton with a new Alfine gear hub.
The thing is: I drive pretty toughly: I drive almost every day on a paved road and I use to jump over from the sidewalk here or there.
That's why I wonder if I stretch the rear triangle to make it fit the Alfine OLN (the way described there: http://www.atob.org.uk/44/epage2.htm), will it still be strong enough to support the way I ride my Brompton? What do you think about it ? (I weight 70kg - 154lbs)

By the way, do you know any other "how to" on the internet ?
I found just another one in German: http://www.bromptonauten.de/umbauten/nexus7-2.html

Thanks :)

parcoju 02-04-09 10:19 AM

It is possible to respace the Nexus Red Band to a 120 mm spacing. I have taken pictures of it and everything, but I haven't had the time to post them up. You simply have to remove all the unnecessary spacers on the left side of the hub and replace the fat lockring with a skinnier standard shimano freehub cone lockring.

I do not think this is the case for the Alfine, however. It seems that the spacing is fixed due to the hub design.

joseff 02-04-09 11:42 AM

I've seen pics of an Alfine on a R&M frog, apparently the owner ground down parts of the hub to bring it down to 118mm.

parcoju 02-04-09 12:54 PM

Ah, so I guess I was wrong about the Alfine.

http://flickr.com/photos/juddparco/s...7613358920756/

I just uploaded a tutorial on how to respace the Shimano Nexus 8 speed from 132 mm to 120 mm.

http://farm4.static.flickr.com/3257/...fbae00.jpg?v=0

You have to remove all these

http://farm4.static.flickr.com/3372/...2fd075.jpg?v=0

Replace the larger cone locknut with a smaller one

http://farm4.static.flickr.com/3414/...d22baa.jpg?v=0

And you get down to this!

http://farm4.static.flickr.com/3095/...71d35a.jpg?v=0

However, you will have to file down the axle to use the anti-rotation washers.

Click the link to my album above if you want the gory details =]

euhmoins 02-04-09 02:36 PM

Hi parcoju,

Wow, what a detailled response, thank you very much for that!
I hope I'll be able to do the same with the Alfine hub (I have one in stock), it may be built differently. What about the chainline ? It is well aligned ?

Again, thanks a lot for help :)

invisiblehand 02-04-09 03:40 PM

What is the OLD on a Brompton? For some reason, I thought it was less than 120 mm ... say 115 mm?

tcs 02-04-09 07:29 PM

Quote:

Originally Posted by mulleady (Post 7300575)
On 2nd thoughts the Nexus Premium hub offers a slightly higher gear at 87" as opposed to the Alfine's 80".

The internal ratios and the cog interface are exactly the same on both hubs.

tcs

tcs 02-04-09 07:34 PM

Quote:

Originally Posted by mulleady (Post 7297701)
The Alfine is listed below:

SGS500

That's the original Alfine hub. The newer release with the upgraded triple roller clutches is the SG-S501.

Best,
tcs

euhmoins 02-05-09 07:57 AM

@invisiblehand: You are right, at http://www.atob.org.uk/44/epage2.htm
they say the rear dropouts have an average width of 108-112mm.

I just measured it: for my brompton, it is 111mm (model 2008).
That would mean I still need to find 9 more millimeters to save
in order fit the "shrinked alfine" (120mm).
Well, at first sight, it doesn't seem that much, but I guess I can't
achieve this without enlarging the rear triangle which brings me back
to my first concern about its solidity after having been stretched.

Furthermore, I wonder how much the removal of the dust cap impacts the longevity of the Alfine.
I use my bike everyday, whether it rains or not.

Thanks a lot for your help.

invisiblehand 02-05-09 01:50 PM

Quote:

Originally Posted by euhmoins (Post 8309185)
I just measured it: for my brompton, it is 111mm (model 2008).
That would mean I still need to find 9 more millimeters to save
in order fit the "shrinked alfine" (120mm).
Well, at first sight, it doesn't seem that much, but I guess I can't
achieve this without enlarging the rear triangle which brings me back
to my first concern about its solidity after having been stretched.

People have been spreading steel frames for a long time.

http://www.sheldonbrown.com/frame-spacing.html

K6-III 02-08-09 10:17 PM

Better idea to fit it with Sturmey 8W. With 19t sprocket it should fit the Brompton rather well.

Dahon.Steve 02-08-09 11:54 PM

Quote:

Originally Posted by K6-III (Post 8329151)
Better idea to fit it with Sturmey 8W. With 19t sprocket it should fit the Brompton rather well.

Does anyone know if the new Sturmey 8 came out yet? It was supposed to eliminate the problems of the old hub. Has anyone tried to fit one on the Brompton?

K6-III 02-09-09 05:19 AM

Well, you can see Yan from Downtube playing with the new Sturmey 8W in this video:

http://www.youtube.com/watch?v=w7mo70lczo4

The XRF8W 115mm 28 hole variant (the one you want for the Brompton, as it has 115mm OLN) appears to be in United Bicycle Supply's 2009 catalog. See if your LBS can order you one through them.

euhmoins 02-09-09 10:34 AM

Hi,
thanks a lot for your reply.
I would take the sturmey archer into consideration only if they made significant improvements compared to the 3 gears version.
Actually, I have never understood why brompton works with sturmey archer beside the obvious fact that they are british.
The XRD3 hub is too heavy, too noisy, cannot be switched under load and is delivered with a ridiculous shifter.
So I'll probably stretch the rear triangle to enjoy a hub of better quality.


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