Cycling UK Forum

I have a 6 speed folding bike..an old Dahon..steel..Does anyone know if it be cold set and widened to 130 mm so it could take a 7 speed hub ..
I know it would be no problem on a normal bike but on a 20 inch wheel folder the chain and seat stays are much shorter?

A 6 on a dahon is most likely a modern (as opposed to ultra 6, which has been obsolete for nearly 30 years) 6 speed freewheel, and 6 and 7 speed freewheels have the same width for all intent and purposes.

Even if you are intending to change the wheel/hub, 6 and 7 speed cassette hubs are both 126mm as standard. Of course some are wider, but only to suit typical frame dropout widths (e.g. 130mm for road and 135mm for mtb), not because they have to be.

Hi,

Are you talking hubs or actually freewheels ?

my folder has 14t - 16 - 18 - 21 - 24 - 28t, 6 speed
my road bike 14t - 16 - 18 - 20 - 22 - 24 - 28t, 7 speed

Is it worth the hassle ? You'd need a new gear selector.
You can get 13t - 15 - 17 - 19 - 21 - 24 - 28t, 7 speed.
I understand 13t is the minimum for freewheels.

rgds, sreten.

FWIW an ultra 6 fitted in the same space as the old 5 speeds.

I have a 6 speed freewheel on the Dahon..it is 126mm between the dropouts.. I want to change this to a 7 speed cassette so I can get a much higher gear..As far as I understand you cannot buy a 126 mm 7 speed cassette hub..so that is why I want to widen the rear hub spacing to 130mm..a new gear changer is not a problem..I have many in my bits box..

V4281051 wrote:As far as I understand you cannot buy a 126 mm 7 speed cassette hub..

If you look you will find them, on ebay or e.g. http://dcrwheels.co.uk/products/hubs/new-old-stock-hubs/.

If you want to spend less and know what you are doing* you can also use any Shimano road rear hub with the typical and very common 10 spline hub-freehub interface (see pic below) and swap the 8/9/10 speed freehub with e.g. this http://www.ebay.co.uk/itm/Shimano-STX-RC-LX-Alivio-Acera-7-SPEED-Replacement-Freehub-Body-FH-M290-/310958369887 and take 4mm off the M10 hollow axle.

Similarly I expect most 130mm hubs with 6/7 speed freehubs which you can still find new (e.g. http://www.ebay.co.uk/itm/REAR-SHIMANO-CASSETTE-HUB-RM-40-36h-NEW-SEVEN-SPEED-/201138418508) can be converted to 126mm simply with suitable spacers.

* pre-checking both tech docs ensuring existing hub has or you can get the correct spacers/cone/seals.

Go for it - you are only talking about 2.5mm on each stay. If it helps to reassure you I spread my 20" wheel Dawes kingpin to take a 130 mm cassette hub from a Sturmey 3 speed which was a lot shorter. 120mm? Or less even, can't remember the normal spacing for a 3 speed