1950's BSA kids' bike rear freewheel sprocket

[Paulmh]

I'm restoring a 1950's girls' BSA "Parabike" and have found a helpful wheelbuilder who can rebuild the wheels after I have taken them completely apart in order to have the rims and hubs re-chromed. So far so good.

On the sprocket side of the rear wheel the captive ball-race is retained in place by a pair of rings, no doubt threaded.
There is an outer ring as follows:

• Marked, "UNSCREW" with an arrow showing that it is a right-hand thread. Also marked with the words, "OIL", "MARK 10" and, "BSA".
• There are a pair of circular recesses, about 2mm diameter and not very deep, diametrically opposite each other, probably to assist in removal of this ring. They are at about 43mm centres and they look too small to be able to take a lot of force.
  

The inner ring has diametrically opposed slots in it, again no doubt to assist in removal, but there is nothing to indicate which direction the thread goes.

Any ideas about removal of these rings and subsequently the captive races? Do I need to find the original special tools for removing them or is there some technique that could successfully be used?

In case anyone is wondering why I'm bothering, it's because I am a Parabike design enthusiast, ever since I had one as a kid. I'm having a new one made, with improvements such as Rohloff gears and belt drive and other excessive indulgences. The girls' version I found on ebay and I'm restoring it for my granddaughter, so she has something similar to mine.

Looking forward to hearing any useful response.

Best wishes,
Paul

 

[Zoiders]

Have you got pictures?

As the original Parabike was a war surplus item and I am not sure if they remained in production postwar, they were commonly called a paratroopers bike but they were also carried ashore at Normandy.

If you are interested in a new Parabike or "Arnhem" bike as they have also been described Pashley manufacture a non folding version called the Tuberider and a Dutch builder offers them as well.

It sounds as if they have used the original hub which was considered disposable, getting the lockrings off may mean fabricating a tool.

 

[Paulmh]

I've now taken off the first ring with the right hand thread and that enabled me to take the drive sprocket and sprocket bearings off - I used needle nosed pliers with points inserted into the two holes and it came off quite easily. The next job is to take the rest of the drive side off and that is held on with the ring that has 2 slots in it. I don't know if that is a left or a right hand thread but guess it is probably left hand and am not sure how to go about it, but the wheelbuilder I'm going to use might know.
Regarding the new bike I'm having made, yes, I know all about the BSA Airborne bicycle as it was known during WW2 and have researched it thoroughly in preparation for the bike I'm having made. Pashley's maximum frame size doesn't suit me and I want the bike to be folding, same as the BSA bike did. Also I want the Rohloff gears and belt drive and other goodies. It should be completed by Christmas.
Best wishes,
Paul