The sketch below is of the extractor I have. I do not know how original it is but it certainly works well. For those interested in making one it clearly does not matter whether the centre bolt is Whitworth, BSF or Metric. The dimension partly missing from the left hand side for the thread diameter is 1.7/16".



Special care needs to be taken removing this design of flywheel and temptation to use methods other than the correct extractor should be resisted. The wall of the flywheel beyond the central hub is not much more than 1/8" thick and the use of a three legged puller on the rim will inevitably distort the whole flywheel and not necessarily symmetrically, leaving it with a severe wobble.

Chris

Thanks Chris.
Made one last week and it works like a charm.
The drawing was all I needed to prompt me along.  Had to teach myself how to do threads, but after seeking some advice it went well.
Again, thanks.
Jonathan (Geelong, Australia)

Hi All
     For those of you without the facilities or skills to make this flywheel extractor, they are now held in LDMCC Prewar Club Spares stocks at a very reasonable price. Available to members only and worth joining the Club if you are not a member for this item only.   Chris.

Quote from: Chris on 08 Nov 2009 at 07:29
Hi All
     For those of you without the facilities or skills to make this flywheel extractor, they are now held in LDMCC Prewar Club Spares stocks at a very reasonable price. Available to members only and worth joining the Club if you are not a member for this item only.   Chris.

Strange you should mention that Chris but having taken delivery of a box of goodies from LDMCC including said extractor it was put to good use on Saturday. Just like this...

My what an interesting thrust washer you have there!

-Doug

Quote from: Doug on 17 Nov 2009 at 00:24
My what an interesting thrust washer you have there!

Yes. I had a feeling that things werent right in that department when we got the flywheel off. I suspect I may find some more items missing when I eventually get in to the flywheel..... like the pressure plate which I think ought to be visible in the first picture above. 4 screws came out easily, the other 4 are not so willing and may well have to be drilled out. Any advice on this most welcome. But perhaps I ought totake this discussion to another thread?

Cheers Mike 8-{>

Hi Mike
   I presume you are discussing the qty 8 screws securing the back plate to the flywheel body. I have found that the only way of getting these out reliably is to use an impact screwdriver. Give them a good soak in WD40 or similar, ensure the slots are clear and then with the impact driver a good bash with at least a 2lb hammer will usually release them. A recent auto jumble purchase of one of these flywheels was so rusty that I could not even see the screws. Wire brushing, a soak in release oil, use of an old screwdriver as a chisel to clean out the residual screw slots and then a good bashing session and I removed all 8. Chris.

Rather than drift a bit away from the topic of this technical article I have moved my comments to a new thread in general discussion here https://www.douglasmotorcycles.net/index.php?topic=3360.0

Cheers Mike 8-{>