Tuesday 4 August 2015

Is my Brompton a long or short wheelbase?

Pre 2004 Bromptons are referred to as short (as opposed to long) wheelbase.

But often we are asked "How do I know of my ?Brompton is long or short wheelbase?"

The easy guess is 'it's a long wheelbase' - as the majority of Bromptons out there are the long wheelbase model - but to be 100% sure there are these two ways to see.

Method 1: Tape measure 

The long wheelbase Brompton is only 3cm / 30mm longer than the short wheelbase version - but this makes enough difference that different cables should ideally be used (rear brakes and hub/derailleur gear cables) to make the fold work optimally.

You can measure (with the Brompton unfolded) from the centre of the front wheel to the centre of the rear wheel.

The long wheelbase Brompton has a length of 1045cm
The short wheelbase Brompton has a length of 1015cm

Measure the distance from front to rear wheel nut to determine if its a long or short wheelbase Brompton

Method 2: Distinguishing features / characteristics - main hinge

Main hinge construction

One of the improvements made to the long wheelbase Brompton was the quality of the main hinge. Instead if being brazed by hand it is now done by machine to make it more consistent and robust in its construction.

The below picture shows the main hinge on a short wheelbase Brompton - you can see that the main hinge is not quite as tidy as the machine brazed version on the long wheelbase model.

Red Brompton folding bike showing older hand brazed main hinge
Brompton folding bike - short wheelbase model with hand brazed main hinge
The hand brazed main Brompton main hinge gives the appearance that the hinge is narrower - as the slope up is thicker, but the hinge clamp required is actually the same width.

The picture below shows the main hinge on a long wheelbase Brompton - you can see the much smoother join made by machine brazed hinge.

Blue Brompton folding bike showing newer machine brazed main hinge
Brompton folding bike - long wheelbase model with machine brazed main hinge
Out of interest - both of the bikes shown above (the long and short wheelbase model) feature the older hinge clamps, which are now available in various colours (yellow, red, lime green and yellow) as well as the traditional black.

More info on hinge clamps - Brilliant Bikes

Wednesday 29 July 2015

Brompton Hub Gear Cable Pulley Assembly - part update

In July (we think) 2015 there has been a small update to Brompton components

The picture below shows the old and new Brompton hub gear cable pulley assembly - it is used to route the hub gear cable (used on Sturmey Archer and SRAM / Sachs 3, 5 and 6 speed setups) through a ninety degree bend (using a pulley wheel inside the assembly to ensure smooth motion of the cable) just before it attaches to the cable anchor and the gear indicator chain.

New look Brompton Gear Cable Pulley Assembly

Not to worry - the new pulley assembly is compatible with Bromptons old and new. Below shows the difference between the old and new version - it's just a change to the look really.

Old (on the left) and New (on the right) Gear cable assembly
Just in case you are not quite sure where it fits - the below picture shows it in position on the Brompton.

Brompton gear cable pulley assembly in place
Brompton Gear Cable Pulley Assemble in place
You can see more and buy it at Brilliant Bikes - here:

Thursday 25 June 2015

More Brompton colour - handlebar clamps

Ready for summer - to brighten up your Brompton, there are some new colour Brompton clamps now available.

Each Brompton has two clamps to lock the frame in place when in the unfolded position as shown in the picture below (it's not the best picture - we used the Brompton bike builder to grab it - sorry!)

Location if Brompton Hinge Clamps

The hinge clamp assembly (QHCA) consists of two parts - the hinge clamp plate (QHCPL) and the hinge clamp lever / bolt assembly (QHCLEVA) - see left.

The hinge clamp plate is available in silver or silver (though we have heard of some people getting them anodised to give extra colour there)

The hinge clamp lever / bolt is easily removed for replacing - no tools required.

It simply unscrews / screws into the frame (you already partially unscrew it when folding the bike)

The new (for 2015) Brompton coloured hinge clamp levers

Now - for the first time ever, the hinge clamp lever / bolt assembly is available in colours other than black ....

Sunflower yellow
Lime green (though we think it's a bit light for lime - more like mint!)

They come display packaged (on re-cycled card of course)

For the full range of hinge clamps - click here

Wednesday 24 June 2015

Which Brompton handlebar type do I have?

It may be simple for those us who have worked on and with Bromptons for years - but many of our Brompton spares and accessories are for specific handlebar types.

Update for 2017

For the 2017 model Brompton, a new M-type / H-type handlebar was released. It's not so high a rise as the old one, so gives less flex. It also has a less pronounced upward bend in the bars.

The change was made to facilitate two other new features for the year:
  • Lock-on handlebar grips (and how the standard 130mm width meaning that other grips - such as the ever popular Ergon grips) don't need to be cut down for fitting.
  • Integrated brake levers / gear shifters / bell - to keep the controls neater
To accomodate the lower rise of the handlebars and keep the fold / ride position the same, the front stem of the bike has increased slightly in length.

So - back to the original question - which Brompton handlebar type do I have .....

If you are not sure which type you have, then it makes ordering the right replacements difficult (gear and brake cables for example are pre-cut to the correct length based upon the type of handlebar your Brompton has)

So here we are ... There are 4 types of handlebar type

The original was the classic M-type, still the most popular with our customers.

Brompton with classic M-type handlebars
Brompton straight / S-type handlebars
Then in May 2005 the S-type and P-type were introduced

The S-type handlebars (shown to the right) give a sporty feel to the ride, with your head down ready for racing away from the lights during the rush hour.
Brompton P-type handlebars
The P-type handlebars (shown to the left) give the rider a variety of riding positions - hence P-type for multi position.

They are generally most popular for long distance touring where, when spending hours in the saddle, being able to ride in different positions can be beneficial.

Brompton H-type handlebars

Last but in no means least was the H-type  - introduced in January 2012 - to cater for taller riders and
the Northern European markets (Holland, Germany, Denmark and Sweden) where a more upright riding style is preferred.

The handlebars used are exactly the same as on the M-type, the difference is that the handlebar stem is approx 2cm / 1 inch longer just below the hinge.

Each Brompton handlebar type has it's own handlebar stem and cable lengths - which means you can;t just change handlebar types if you want the fold to function correctly.

Want to get some new Brompton handlebars? Then try us at Brilliant Bikes

If you are looking to buy a new Brompton  - then why not use the Brompton website - it will help guide you through making the right choice (click here) or come and visit Brilliant Bikes in Chobham where we have a large range of Bromptons including a demo in stock - you can see our list of in-stock Bromptons by clicking here.

Tuesday 5 May 2015

Brompton 10 degree brake lever

About Brompton 10 degree brake levers and new cable end

In 2012 Brompton changed the size of the nipple used on their brake cables from a proprietary size to a standard brake nipple size.

The new (standard - as you would find on a Hybrid / MTB bicycle for example) nipple is slightly smaller than the previous one used by Brompton.

This is good if you want to use non-Brompton brake cables but bad if you have some of the older 10 degree Brompton brake levers.

Open clevis

Brompton 10 degree brake lever - Open Clevis

Because of the reduced nipple size, some of the older levers (those with an open clevis) must be replaced. These are so called 10 degree levers (this is the angle at which the cable fed out from the lever). They can be identified as they have a double metal band where the lever is secured to the handlebars. See picture

Some older 10 degree brake levers had an open clevis as shown in the below picture:

(the clevis is circled in red - it's the part into which the nipple sits)

Brake clevis on Brompton 10 degree lever

Closed Clevis

The closed clevis brake lever was introduced in August 2008

Some 10 degree levers (as shown below) and the newer 30 degree levers and (introduced in 2013) aluminium brake levers from Brompton have what is known as a closed clevis.
Brompton 10 degree lever with closed clevis
With the closed clevis (even in conjunction with the smaller brake nipple) there is no risk that when the cable is slack that the nipple falls out rendering the brake useless.

As you can see from the picture - with the closed clevis the cable has to be fed through a hole, meaning it can't fall out.

Brompton with the 10 degree brake levers with an open clevis should be replaced with either the 30 degree or new aluminium brake levers.

All Brompton brake parts (cables, callipers and levers) for sale can be found here:

Wednesday 11 February 2015

Brompton chain sizing guide

Which chain do I need for my Brompton?

Over time chains and sprockets wear out. Due to the workhorse nature of the Brompton and the fact that the drivetrain is closer to the ground than on larger bikes (it picks up more dirt / grit) they can wear even quicker.

Choosing the correct chain for replacement can be confusing so we made this guide to help.

But first - if you are replacing the chain or rear sprocket(s) then we recommend replacing both parts the chain and the sprocket. We describe it as an old married couple - they get comfortable with each other and wear at about the same rate.

So remember - if you replace the chain alone then the chain may well slip - and the same if you replace just the chain. Check back for our next article on choosing the correct sprocket.

How many teeth does your chain ring have?

The first place to start is to count the number of teeth on the front chainring. Brompton supply them in 3 sizes: 44 teeth, 50 teeth and 54 teeth.

If your Brompton is a 3 speed or 6 speed then the chances are that this is a 50 tooth front ring (as that's the standard) - though it could have been changed to lower gearing (44T) or higher gearing (54T)

If your Brompton is a single or 2 speed version, then chances are it has 54 teeth (as that's the standard) - but again the gearing may have been lowered.

When you have made a note of this - count the number of sprockets (there should be one or two) and the number of teeth on the largest sprocket.

So which chain width?

Now you know the number of teeth on the front and rear - choosing the chain is quite easy!

Historically there used to be two widths of chain used by Brompton:

  • 1/8 inch used on single sprocket bikes (1, 3 and 5 speed) - the part code ended in a W (for wide) such as QCHAIN100W
  • 3/32 inch used on derailleur equipped bikes (2 and 6 speed) - the part code ended in DR (for derailleur) such as QCHAIN100DR
That gave us a total of seven chains to choose from

Since 2013 (we think that was the correct year), all new Bromptons have been equipped with the narrower 3/32 inch chain (which incidentally is easier to remove and install as it has a SRAM power link so no special chain tool is (normally) required.

So, we will assume you are going to replace the sprockets - you are going to aren't you? 

That reduces the number of chains to choose from to four - and which of the four depends upon the sprocket and front chain ring combination as shown in the table below.

The below list shows for each front chain ring size, based on the largest rear sprocket which Brompton chain is required:

44 Tooth Chainring
12t/13t/14t   - QCHAIN096DR (96 links)
16t/15t - QCHAIN098DR (98 links)

50 Tooth Chainring
12t/13t (3 speed default) / 14t - QCHAIN098DR
15t/16t (6 speed BWR default) - QCHAIN100DR

54 Tooth Chainring
12t (single speed default) / 13t / 14t - QCHAIN100DR
15t/16t (two speed default) - QCHAIN102DR

And there you have it - all you need to choose your new shiny chain.  Check back for part two - choosing the correct replacement sprocket.

Brompton chain size document
Brilliant Bikes - Brompton chains

Thursday 1 January 2015

Brompton new colours for 2015

The New Year - 2015 sees some new frame colours supplied by Brompton

Black (the most popular colour) and white (collectively known as the mono range), remain the cheapest (there is a surcharge for the other colours)

Brompton Lime Green colour - new for 2015
2015 Brompton Colours

The new Brompton colours introduced are:
Berry Crush (shown below)
Cherry Blossom
Lagoon Blue
Tempest Blue (this was actually available in the past and has been re-introduced)
Lime Green (shown to the left here)
Ivory (this was available

As with previous years you can choose a bike in just one colour - or with the main frame in one colour, with the extremities (rear frame/triangle, handlebar stem and forks) in a second colour.

2014 Brompton Colour list

Some of the colours previously available have now been discontinued - but don't worry if you need to replace a broken part.

Brompton still supply frame parts for all colours that they have ever produced - even the old gloss paint finish.

There is however a slight price and possibly time penalty for the non-current colours, as they have to be painted specially.

Any replacement frame parts must be supplied and fitted by an authorised Brompton dealer - so no DIY replacements.

Brompton Berry Crush - New for 2015
Brompton Cherry Crush - Another fruity new 2015 colour
The complete list of 2014 Brompton colours is as shown in the list below - those with a line through are no longer available on new 2015 bikes:
Turkish Green
Cobalt Blue
Racing Green
Sage Green
Desert Sand
Hot Pink
Apple Green
Arctic Blue
Raw Lacquer
Titanium parts are still in short supply, meaning that it's difficult to get superlight Bromptons - though it is rumored that this could be rectified for good in 2016
External Resources:
Brompton Bicycle
Brompton spare parts and accessories at Brilliant Bikes