I have never altered the oil holes in the many BSA singles I have owned and rebuilt over the last 45 years...It's not necessary in my opinion....

If you remove the oil flinger plate you will need to substitute a spacer of the same thickness as the crank position in the cases is affected when you remove it...The engines run OK without the plate but working on the principle that BSA had a good reason for putting it there I always fit one...Ian

email (option): ian@wright52.plus.com

Interesting comment regarding "early fork yokes with rubber bushes"?

My Own WM20 is from 1939 & Im unsure which type of forks are correct for this year .

Would be very appreciative if a knowledgeable member could help please ?

Many thanks in advance,

Also which headlamp is correct for My machine please ?

Steve ..

email (option): s.foster11@blueyonder.co.uk

Building any 1939 or earlier WD motorcycle to a high standard reflecting factory specification is a time-consuming and expensive business that involves huge amounts of research which effectively never ends. Hugely rewarding if you enjoy that sort of thing (and I do, I wouldn't want to put anyone off:relaxed: )

Almost every contract had differences and many of them are not immediately obvious. In this case, the early machines had an anti-vibration handlebar mount...but that's just the start.

The main reason that it's all so difficult is that most 1939 machines were rebuilt three or four times before leaving service with all damaged or worn parts replaced by the latest spec or used parts from another machine...plus the early parts are often common to other pre-war machines so you'll find yourself competing with Gold Star rebuilders for many of the nice bits.

Is your engine also from 1939 ? It too will have a number of detail differences. If not, perhaps more accurate to portray a 'Rebuilt' motorcycle or to base it on the date of the engine (which has a much more visible number).

The headlamp for a 1939 bike is the 8" (roughly) DU142 with switch panel, flat 'Difusa' glass and WD type lower screw fixing (not available as a pattern part as far as I'm aware so would have to be modified).

How detailed a rivet-counter do you wish to be ?

Hi,

Rik's list is accurate. I have the lower screw fixing's for sale, these are original. It's easy to change a replica DU142 headlight to fit these scre fixing's. See below a photo of my original BSA KM20 from 1939 and a photo of the screw fixing set (consisting of 3 parts).

Regards,
Bastiaan

email (option): wdmotorcycles@gmail.com

Very nice, Bastiaan. Something to aspire to for anyone building a '39 bike.

I've seen odd parts of the headlamp retainers for sale over the years but never a complete set. Anyone converting a pattern headlamp will still need a slotted reflector and an illuminated CZ27 ammeter...It never ends which is part of the hobby for some of us.

Thank you for the compliment Rik.
You are right... :wink:

email (option): wdmotorcycles@gmail.com