Cycling UK Forum

Brucey wrote: ↑14 Feb 2024, 6:17pm It is much more likely that the hubshell thread will be stripped if my advice re. a 'frankeninternal' is not followed.

Can I ask why ?

( I thought SA ballring/shell threads were forward and backward compatible.....although I couldn't get a 1980 AW ballring to screw all the way into a 1965 FW shell !)

Ditto ......I presumed the LH end dog ring/gear ring for the low gear pawls is less likely to get damaged than the pawls themselves? ......if it is a wear issue ....rather than the pawls or one of the pawls being gummed up and not moving properly.

Yes, subject to having one with the right axle length to fit the dropouts...and checking/adjusting OLD.....with spacing same so wheel centres.

( presumably no oil port so will need to oil via axle)

(My Raleigh Randonneur is out by a similar amount between the chainstays.... but I have a 130 wheel in 126 drop-outs and I think the dimple on the chainset side weakens it laterally....so that one has moved more........

as it seems to ride fine.....with or without hands on the bar.....I've just not got round to cold setting it.....)

Brucey wrote: ↑10 Feb 2024, 3:38pm the risk you might be running is that repeated rethreading of the ball ring on the wrong start will cause the hubshell thread to strip. Since the parts are not exactly toleranced to the 'n-th' degree, this is not an idle worry.

explanation appreciated.

( It has always bugged me that I've seen the SA guidance to mark up the positions before removing the ballring......but never with a reasoning given.)

Certainly on some of my hubs the ballring screws in further on one of the thread starting points. ( based on the times I've marked-up the hub and ballring and tested)

What I've not worked out is if it really makes any significant difference as the change in centering of the wheel will be very small...and similarly inside the hub the changed spacing small?

jimlews wrote: ↑2 Feb 2024, 5:06pm And there displayed in plain sight is the twin thread.

And here an early AW shell thread with matching twin thread. On later ball rings ( can't remember if also on hub shell) the two threads start 180 degrees apart......so is there really no need to mark the hub/ballring before opening on this type of early double thread?.......just press two parts together; rotate backwards until feel/hear it click over the thread start, then keep applying finger pressure as you engage threads and start to screw in ball ring?

That's useful advice.......I won't contemplate a tour with the K505 clutch then

(The 2 rows of ring gear dogs looks like a daft SA decision.....particularly as the 3 speed K hub that preceeded the AW appears to have a ring gear with a single set of dogs, spanning 2 & 3rd gear, as then used in later AW"s)

I aquired both old hubs out or curiosity to see & compare original type components with the 1980's ones I've been using.

I will at some point lace up the 1937 hub in a 32 hole rim for use. I reckon the 1939 damaged gear ring will still work, so I will probably test it on that wheel... If I can find a good original gear ring though....I'm tempted to knock up a Bitsa Bike around an original componented AW& perhaps do a tour.

(Looking at the damage in the '39 hub I think it was a mini-catastrophy, like broken ball cage or ball falling in.....rather than long term wear. But the the clutch in the '37 hub is years of wear)

Obviously the above is boring, so here is a picture of the thrust washer with machined in recess for the spring (lush!): [Edit: this is an post war thrust washer and not the 1st type]

rogerzilla wrote: ↑2 Feb 2024, 3:39pm Here's one I did two weeks ago. Hub not built into a wheel, gripped between my knees. Flat-ended punch and big hammer. It barely marks it.

Do you have holes in your knees though?

Brucey wrote: ↑1 Feb 2024, 3:27pm

hoogerbooger wrote: ....the very elaborate ramped clutch.....sitting on a later type clutch carrier......

it is indeed the later style of clutch carrier, but the cruciform clutch is, I think, that way because of damage, not ramps......

On second inspection I agree. It's worn to a ramped shape. Worn on both top and bottom of clutch.....so I presume that means it's been misadjusted in both directions ( between 3rd & 2nd) over the course of it's life?

[ Edit: Colwood Wheels confirmed it is the early ramped clutch showing relatively little wear]

This 1939 AW looks mostly original, I think. Just LH cone newer is my guess. It's 'machined art'.It has the original type gear ring with two separate sets of drive dogs, the LH set quite mashed.
Edit: Can't quite get my head around why there are 4 dogs on the RH side (1st gear) rather than just 2 as stops for the pawls? Or why they used the original design of to separate sets offset dogs rather than the later combines set of dogs? [ Edit: having spoken to Colwood Wheels the RH clutch components and spring are not original. In the first few years the 'prototype' parts included a much stronger spring to work with the quadrant and barrel shifters. Then when the trigger shifter was released (1937/38 ?) The spring was weaker )]

(MickF: don't read the below)

I Remembered this thread this morning after having a two day battle with a 1939 AW ballring.

I had used a 6 inch nail as the punch (springy and softer than the ball ring) strike at half past 10........then carry on striking for the rest of the day!!

Had soaked with plusgas the previous night......and tried freezing it & then warming with a camping stove.....several times.....but by evening still no joy.

As a last resort, passed my bedtime, last night I put it in the oven at 150 degrees for 5mins or so.......then juggled the hot potato with gloves to the garage and tried a last time.....to no avail. So I decide to give up.

This morning I remembered this thread......and thought may be it wasn't on a soft enough surface and the screw on sprocket teeth were bottoming on the bench........so I got the hub out the box ......and the ball ring just easily unscrewed by hand.........MAGIC

So my new technique is give up and put it in a box for a while !

If you are very excitable and have a weak heart STOP LOOKING NOW

Have just aquired a 1937 AW hub. It's a bit of a 20th century mash-up inside.....various original looking type parts ? including the more or less symetrical low gear pawls and the very elaborate ramped clutch.....sitting on a later type clutch carrier.

So for those interested some piccis.

So the answer is it won't be a simple conversion...whole rear triangle change....if they sell them separately, new hub, derailleur and ritger new left gear lever or gubbins to convert it to 4 speed from 2....and perhaps more.

For post 2017 Bromptons there are kits like the following that involve less work......but don't seem to include any plastic chain guide/ dust cap..... which looks important to keep water out of the hub.....in Blighty ?

https://www.brommieplus.com/portal_c1_c ... &up_page=1