I had one of these (new and unused) which -having realised I'd probably never use it myself- I have recently built up and sold to a fellow forum member. Since the specification and internal details of the hub don't seem to be well documented anywhere and I had dismantled it anyway (in order to make it so that it could be lubricated via a grease port) I thought I'd share the details here.
The hub uses a 14mm diameter hollow aluminium axle, and there are four 6902-2RS bearings; two for the hubshell, and two for the freewheel body.
- axle assembly
the bearings are separated by spacers throughout. The parts seem nicely made and the bearings are a nice fit in the hubshell; not too tight and not too loose. The whole lot is retained by the axle end adaptors which screw into the axle and also allow (by use of longer adaptors and spacers) respacing from 120mm to 130mm or larger. When disassembling you can use two 17mm spanners on the axle ends; one or the other will come undone, and this will allow the whole axle to be withdrawn if necessary. There are flats on both ends of the axle itself, so that the other axle end can be unscrewed if necessary.
In the hub I had, I drilled the hubshell so that the main bearings could be lubricated. However the freewheel mechanism needs to be slid off the axle to allow access for lube to the pawls etc, and once it is off, the spacer between the bearings in the freewheel body can be slid to one side so that lube can be introduced between the freewheel body bearings. In my hub, all four bearings had their inner seals removed, so that a suitable lube (eg a semi-fluid grease) can be used in the freewheel body and the hubshell itself, with free lube access to the bearings. There are six chunky pawls, so it looks as if it ought to be strong enough.
The external parts are shown below;
- external parts
being from (left to right), the selector disc, the dog ring, sprocket and lockring respectively. They are not in the correct order; the dog ring goes behind the selector disc when the hub is assembled. The dog ring engages with a matched opening in the hubshell, and that gives the 'fixed gear' function. The dog ring has a slight radius on one side, and that side faces the hubshell. There are six small springs which disengage the dog ring; in the photo the exact size is noted since these springs may need to be replaced at some point. 0.29mm is the 'wire diameter' of the spring.
The lockring uses a 38mm spanner to tighten it. Once the lockring is off the sprocket, selector disc and dog ring come off, and the six small springs can then fall out too. The sprocket is a nine-spline sprocket with a DX pattern spline, so shimano UG, shimano DX, Sturmey Archer S3X, Brompton 6s, and modified HG sprockets will fit, amongst others. Standard three-lug IGH sprockets will also fit, since the Affix spline has curved roots.
If necessary the freewheel body can be removed as a complete unit (i.e. with the sprocket and selector disc still attached).
Hubshell details; flange spacing ~54mm, flange drilling 58mm PCD. Drilled 32h, for 14/13G spokes.
- assembled hub
freewheel mode;
fixed mode
I hope the above information is of some use to others.
cheers