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a couple of brompton questions

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John

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May 14, 2013, 10:56:19 AM5/14/13
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Hi,

I know the max rated load for the brompton is 100kg. The problem is that
I'm nearer 120kg. I'm also 6ft 5in. In summary, my problem is that
I'm built like a brick sh1thouse, and I'd like a brompton because it
folds small.

I know I'm out of specification for a standard brompton. But I see from
their website that they are very customisable. So I'm hoping this
newsgroup's knowledgable members can advise: can a brompton be modified
so that I am within its spec? Can it cope with my height?
If so, can you also advise if there is a good heavy-duty (foldable)
trailer that will go with it?

many thanks,

--
John

geomannie

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May 14, 2013, 11:36:57 AM5/14/13
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I can speak with a little experience. My brother-in-law borrowed my
Brompton and it was apparent that his weight was an issue. The problem
was with the compression/suspension rubber that was squashed very flat
and was clearly overloaded. I didn't ask what he weighs but my guess
would be about 16-17 stone (100-105kgs). He only rode it the once so I
have no idea what long-term damage may have resulted.

There are also a lot of reports about the wheels giving problems for
heavier riders. I imagine that you could build up a set of stronger
wheels than the standard, but the problem of the compression rubber
would remain.

Also being 6' 5" you might just be too big even with the standard
extended seatpost. I am 6" and I have only 1 cm extra to play with on
the extended post myself. You might have to get a custom post made.

I am sure someone else knows better.

Cheers

geomannie

Alan Braggins

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May 14, 2013, 1:21:41 PM5/14/13
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In article <kmtl1q$d7$1...@dont-email.me>, geomannie wrote:
>On 14/05/2013 15:56, John wrote:
>> Hi,
>>
>> I know the max rated load for the brompton is 100kg. The problem is that
>> I'm nearer 120kg. I'm also 6ft 5in. In summary, my problem is that
>> I'm built like a brick sh1thouse, and I'd like a brompton because it
>> folds small.
>>
>> I know I'm out of specification for a standard brompton. But I see from
>> their website that they are very customisable. So I'm hoping this
>> newsgroup's knowledgable members can advise: can a brompton be modified
>> so that I am within its spec? Can it cope with my height?
>> If so, can you also advise if there is a good heavy-duty (foldable)
>> trailer that will go with it?
>>
>> many thanks,
>>
>I can speak with a little experience. My brother-in-law borrowed my
>Brompton and it was apparent that his weight was an issue. The problem
>was with the compression/suspension rubber that was squashed very flat
>and was clearly overloaded. I didn't ask what he weighs but my guess
>would be about 16-17 stone (100-105kgs). He only rode it the once so I
>have no idea what long-term damage may have resulted.

Is that the standard rubber, or the "firm" option?
http://bromptonranger.blogspot.co.uk/2010/02/brompton-hard-suspension.html

Allegedly putting a hose clamp around the middle also helps.

Then there are more exotic possibilities:
http://www.ebay.co.uk/itm/Wworks-Brompton-Steel-and-Elastomer-Suspension-Cone-Unit-150-New-and-Rare-/130869678681?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item1e7870d259
http://kamoya.info/11_41.html
http://www.ebay.co.uk/itm/Birdy-BD-1-Multi-S-Rear-Suspension-Red-Silver-Brompton-Elastomer-Spring-New-/130869671475?pt=UK_sportsleisure_cycling_bikeparts_SR&hash=item1e7870b633


>There are also a lot of reports about the wheels giving problems for
>heavier riders. I imagine that you could build up a set of stronger
>wheels than the standard, but the problem of the compression rubber
>would remain.

It certainly ought to be possible to make 16" wheel hugely strong,
though the range of hubs that fit might be limited. It's not as if
a Brompton rider is likely to be riding over big rocks off road or
doing jumps in BMX parks.


>Also being 6' 5" you might just be too big even with the standard
>extended seatpost. I am 6" and I have only 1 cm extra to play with on
>the extended post myself. You might have to get a custom post made.

I'm 6'3" and found a Brompton with a standard (not extended) post was
practically unridable, but the telescopic post was fine. I didn't check
how much spare there was, but
http://www.brompton.co.uk/our-bikes/bike-explorer/6/seat-post
says it's longer than the extended.

That doesn't mean it'll take the weight though.

But I'd also be worried about the frame. That's a lot of leverage to be
putting on a long seatpost. And that's something that can't easily be
modified or customized (other than the titanium option - I don't know
if that has the same weight limit, but I suspect you pay for a lighter
bike, not a stronger one, and the main frame is the same anyway).
cf. http://www.brompfication.com/41-titanium-seatpost.html which has
the same 100kg limit.

Biggles

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May 15, 2013, 4:03:40 AM5/15/13
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On 14/05/2013 15:56, John wrote:
I'm 6'4" 105 Kg
Telescopic seat post, P handlebars and firm suspension.
Subjective opinion but it *feels* like I'm riding on the limit of the
Brompton's design (OK that may be because I know the rated load is
100Kg!). As such I ride it with a bit of respect - avoiding any shock
loading - but I do ride it fast and have had no problems with any part
of it. I would think that 120Kg is pushing the design too far BUT you
may get away with it if you ride it carefully and avoid shock loads.

My inside leg is about 35" and I don't have the seat post quite at the
highest position so I think you may find it long enough.

Whatever you do, try one with the relevant bits on it before you buy.

Biggles

Alan Braggins

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May 15, 2013, 5:58:53 AM5/15/13
to
In article <slrnkp4sd...@chiark.greenend.org.uk>, Alan Braggins wrote:
>In article <kmtl1q$d7$1...@dont-email.me>, geomannie wrote:
>>On 14/05/2013 15:56, John wrote:
>>> Hi,
>>>
>>> I know the max rated load for the brompton is 100kg. The problem is that
>>> I'm nearer 120kg. I'm also 6ft 5in. In summary, my problem is that
>>> I'm built like a brick sh1thouse, and I'd like a brompton because it
>>> folds small.
[...]
>It certainly ought to be possible to make 16" wheel hugely strong,

Allegedly while the older wheels had poor reputations, they have been
improved recently:
http://road.cc/content/news/67315-new-brompton-products-cycle-show

Other possibilities:
http://www.atob.org.uk/bicycle-accessories/brompton-hub-brake/
http://www.stradawheels.co.uk/shop/brompton-wheels/


>But I'd also be worried about the frame. That's a lot of leverage to be
>putting on a long seatpost. And that's something that can't easily be
>modified or customized

Not impossible though:
http://www.velovision.com/storyimages/2013/princetandem1.jpg
http://www.flickr.com/photos/marcusjb/2895676421/

Maybe you could replicate the extra bracing on the front section
(and possibly the rear rack, which looks as if it might be reinforcing
the rear triangle a bit rather than just bolted on, but maybe it's just
painted).

Steve Parry is probably the man to talk to about heavily modified Bromptons.
I don't know if the contact information on http://www.foldsoc.co.uk/sp.html
is still valid - but I can't find anything better.

Zebee Johnstone

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May 15, 2013, 6:50:41 AM5/15/13
to
In uk.rec.cycling.moderated on Wed, 15 May 2013 10:58:53 +0100
Alan Braggins <ar...@chiark.greenend.org.uk> wrote:
>
> Steve Parry is probably the man to talk to about heavily modified Bromptons.
> I don't know if the contact information on http://www.foldsoc.co.uk/sp.html
> is still valid - but I can't find anything better.

It is probably worth subscribing to the yahoo group BromptonTalk as
there's a wide range of people on that and I think some are fairly
hefty.

Zebee

Peter Clinch

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May 15, 2013, 9:44:55 AM5/15/13
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On 15/05/2013 10:58, Alan Braggins wrote:

> Steve Parry is probably the man to talk to about heavily modified Bromptons.
> I don't know if the contact information on http://www.foldsoc.co.uk/sp.html
> is still valid - but I can't find anything better.

Ben Cooper at Kinetics is maybe worth a shout too. He's not officially
a Brompton dealer any more but makes things like Rohloff kits for them
and is probably knows about the engineering as well as anyone outside
the Brompton factory... When the general diagnosis on my rather rotten
rear triangle was �100 for a new one he just pulled out the torch and
brazed up my original and charged �30 while I went and played on his
Moulton AM for an hour.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net p.j.c...@dundee.ac.uk http://www.dundee.ac.uk/~pjclinch/

Danny Colyer

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May 15, 2013, 3:08:53 PM5/15/13
to
On 15/05/2013 14:44, Peter Clinch wrote:
> On 15/05/2013 10:58, Alan Braggins wrote:
>
>> Steve Parry is probably the man to talk to about heavily modified Bromptons.
>> I don't know if the contact information on http://www.foldsoc.co.uk/sp.html
>> is still valid - but I can't find anything better.
>
> Ben Cooper at Kinetics is maybe worth a shout too. He's not officially
> a Brompton dealer any more but makes things like Rohloff kits for them
> and is probably knows about the engineering as well as anyone outside
> the Brompton factory... When the general diagnosis on my rather rotten
> rear triangle was �100 for a new one he just pulled out the torch and
> brazed up my original and charged �30 while I went and played on his
> Moulton AM for an hour.

It would also make sense to contact Avon Valley Cyclery in Bath, as they
specialise in folding bikes. They're likely to know whether it's
practical to modify a Brompton as required and, if not, to suggest a
sensible alternative:
http://www.avonvalleycyclery.co.uk/contact-us.aspx

--
Danny Colyer
"I'm riding a unicycle with my pants down. This should be every boy's
dream." - Bartholomew J Simpson

John

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May 23, 2013, 2:03:26 PM5/23/13
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On 2013-05-15, Danny Colyer <news...@colyer.plus.com> wrote:
> On 15/05/2013 14:44, Peter Clinch wrote:
>> On 15/05/2013 10:58, Alan Braggins wrote:
>>
>>> Steve Parry is probably the man to talk to about heavily modified Bromptons.
>>> I don't know if the contact information on http://www.foldsoc.co.uk/sp.html
>>> is still valid - but I can't find anything better.
>>
>> Ben Cooper at Kinetics is maybe worth a shout too. He's not officially
>> a Brompton dealer any more but makes things like Rohloff kits for them
>> and is probably knows about the engineering as well as anyone outside
>> the Brompton factory... When the general diagnosis on my rather rotten
>> rear triangle was �100 for a new one he just pulled out the torch and
>> brazed up my original and charged �30 while I went and played on his
>> Moulton AM for an hour.
>
> It would also make sense to contact Avon Valley Cyclery in Bath, as they
> specialise in folding bikes. They're likely to know whether it's
> practical to modify a Brompton as required and, if not, to suggest a
> sensible alternative:
> http://www.avonvalleycyclery.co.uk/contact-us.aspx
>

Hi folks thanks for all the advice. Brompton *eventually* got back to be
and said the maximum load is 110kg plus 20kg luggage so it looks like I
can do it. It's just that I can't carry my weekly shopping on my back as
well ;)

--
John

Peter Clinch

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May 23, 2013, 3:36:37 PM5/23/13
to
On 23/05/2013 19:03, John wrote:

> Hi folks thanks for all the advice. Brompton *eventually* got back to be
> and said the maximum load is 110kg plus 20kg luggage so it looks like I
> can do it. It's just that I can't carry my weekly shopping on my back as
> well ;)

See http://stein.dommel.be/brompton/chapters/Luggage.html especially the
bit at the end. Though further note that Ben Cooper suggested to me
that Brompton's guarantee had had a clause added with small print to the
tune of "but not if you're Dave Holladay".

Zebee Johnstone

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May 23, 2013, 4:56:08 PM5/23/13
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In uk.rec.cycling.moderated on Thu, 23 May 2013 19:03:26 +0100
John <comp...@gmail.com> wrote:
>
> Hi folks thanks for all the advice. Brompton *eventually* got back to be
> and said the maximum load is 110kg plus 20kg luggage so it looks like I
> can do it. It's just that I can't carry my weekly shopping on my back as
> well ;)

Or pick up a CArry Freedom City trailer.

Bike folds and straps to the top of the trailer making an easily
managed wheeled package for the train.

If you do a specific shopping trip then managing both without taking a
lock to lock up one might be tricky but not impossible.

I find the City + Brom combination to be amazingly useful.

Zebee

David Damerell

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May 24, 2013, 2:24:11 PM5/24/13
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Quoting John <comp...@gmail.com>:
>If so, can you also advise if there is a good heavy-duty (foldable)
>trailer that will go with it?

Carry Freedom make the "City" foldable trailer. No idea if it's good, but
their other trailers are.
--
David Damerell <dame...@chiark.greenend.org.uk> Kill the tomato!
Today is Teleute, June.
Tomorrow will be Oneiros, June.

Phil Cook

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May 24, 2013, 3:34:49 PM5/24/13
to
On 24/05/2013 19:24, David Damerell wrote:
> Quoting John <comp...@gmail.com>:
>> If so, can you also advise if there is a good heavy-duty (foldable)
>> trailer that will go with it?
>
> Carry Freedom make the "City" foldable trailer. No idea if it's good, but
> their other trailers are.

I have one of they. it is rather more of a faff to fold than the bike
but it does slip into tiny spaces. The courier bag slung hammock style
for "stuff" does a reasonable job but beware of bulges causing it to
rub on the tyres. The wheels are itty-bity 12.5" and benefit from
angled valve inner tubes, there's not much space to get a pump head on.

It is also worth noting that the Carry Freedom Y-Frame trailers have
detachable wheels and thus store flat.
--
Phil Cook

Phil Cook

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May 24, 2013, 3:37:19 PM5/24/13
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On 24/05/2013 20:34, Phil Cook wrote:
> On 24/05/2013 19:24, David Damerell wrote:
>> Quoting John <comp...@gmail.com>:
>>> If so, can you also advise if there is a good heavy-duty (foldable)
>>> trailer that will go with it?
>>
>> Carry Freedom make the "City" foldable trailer. No idea if it's good, but
>> their other trailers are.
>
> I have one of they.

Bought it for rather less than the current �400 asking price though!!!
--
Phil Cook

Zebee Johnstone

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May 24, 2013, 5:30:00 PM5/24/13
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In uk.rec.cycling.moderated on Fri, 24 May 2013 19:24:11 +0100
David Damerell <dame...@chiark.greenend.org.uk> wrote:
> Quoting John <comp...@gmail.com>:
>>If so, can you also advise if there is a good heavy-duty (foldable)
>>trailer that will go with it?
>
> Carry Freedom make the "City" foldable trailer. No idea if it's good, but
> their other trailers are.

I have one and like it.

I like it because it folds up neatly when not in use, and if I use it
with the Brom I can fill the trailer's bag up with stuff and strap the
folded Brom on top when using the train or otherwise can't have them
both unfolded and linked.

The City makes an easy to manage handcart that's usable in most place.
Narrow shop aisles can be difficult with the Brom+trailer package as
though it does have casters so you can roll it on the narrow side
that's not ideal for shopping.

If I'm in that situation I carry a lock and lock the trailer up
outside and take the Brom inside. Trailer less likely to be nicked I
figure.

Zebee
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