Simplex free hub springs - help needed

[pwhiffin]

I have started to restore/repair a classic sun bike. it has a simplex freehub. When I stripped it down one of the pawl springs has broken. Does anyone know where I can locate spares and is it simple to fit (I can't see how to take the broken one out). The photo shows the non-broken spring.

 

[pigman]

Isn't that the inner body of a freewheel rather than a freehub as you put it? If so, the freewheel is a consumable part.
Clamp the thing in a vice, screw it off using the wheel like a steering wheel and buy a new freewheel

 

[jim haseltine]

Yeah, that's the remains of a screw-on freewheel. Take it off and fit a new unit. If I remember correctly, Simplex freewheels started out as either badge-engineered Regina units or the same manufactured under licence then sometime around the late 80s/early 90s modified part of the design to use Maillard/Atom style outer bodies.

 

[keithglos]

Whatever you decide the remains of the freewheel will have to be removed. If you have a vice, clamp the freewheel and turn anticlockwise. Overtightening the vice will squeeze the part into the threads making removal much harder. If you plan to reuse the part protect it from further damage.
We used to make suitable pawl springs from a single strand from a suitable old brake inner wire.

Simplex freewheels in the 60s were far better quality than regina, and the threads were not the same. In 1956 I put a regina double cog (for a 13 top gear) on to a Simplex to make a 6 speed, I had to search through about 30 Regina double cogs to find one slack enough to fit the Simplex.
Regina machining and case hardening was variable, often they did not run straight. But were easier to get a suitable range of gears. Simplex smallest cog was 14.

Keith

 

[pwhiffin]

All, thanks. Yes I was trying to sevice the innards and have now taken the easy option of replacing the freehub. The old freebub came off fairly easily (I know they can be terrible to get off).

 

[ZG862]

Hi P. There's a terminology distinction that I think you may be missing. Modern hubs are generally known a freehubs since the unidirectional drive element (pawls, springs and the like) are an integral part of the hub construction (to allow the outer bearing to be placed closer to the dropout). In the olden days, we had a separate freewheel with integral gear cogs that threaded on to the hub as a unit (sometimes also referred to as a "block"). Whilst the blocks could often be disassembled and bearings changed, it was generally pointless to do so since the gear rings themselves would be worn out at this point (although some designs allow them to be reversed to double their life).
What Pigman, Keith and Jim are telling you is that your picture shows the (dead) body of a freewheel which (given that it is on a steel hub and rim) would be unlikely to be worth saving. They are normally pretty straightforward to get off in one piece provided that you have the right tool; this may be worth bearing in mind for the one you've put on there now (hope you put a little grease on the thread). No chain whips or drifts required: Tool in vice, wheel in tool, hold wheel rim, twist. If there's a pile of small ball bearings and springs all over the floor, you've done it wrong.

 

[Old Ned]

I would add that if it is a quick release hub then use the skewer and tighten the 'nut' end down onto the freewheel remover tool - but only enough to hold it in place (VEERY slightly loose) to give it room to move once the initial tightness is gone. This will help to alleviate damage to the freewheel's extraction slots/notches/protrusions if the remover slips in the process.

 

[jim haseltine]

I remember showing that method to an apprentice at our shop. Unfortunately when he had need to use it the part he didn't remember was to remove the skewer once the freewheel was loose - I walked into the workshop to see a wheel with a remover in the vice and very red faced lad forcing it around like a bus driver taking a tight corner, I wasn't even able to shout 'STOP' before the skewer sheared and rocketed vertically from the axle to dent the ceiling.

 

[keithglos]

The better way is to tighten the QR as much as you can. The pressure helps release the block. Loosen the qr as soon as the freewheel releases.

 

[ZG862]

The pressure helps release the block.

How? The block is threaded on to the hub and tightened primarily by pedalling torque (i.e. I've not encountered thread lock). Removal tools vary in design but are pretty much either notches or splines. I agree that the QR would help prevent the wheel jumping out of notches as Ned says, but can't see how pushing the block's thread onto the hub's thread could help release it. If it is really stuck (presumably through corrosion as any cross threading would be a whole other world of pain) I would recommend penetrating oil or even heat but I'm always open to new ideas; Can you explain how the QR helps?