attempting to attach pics of my bike, demobbed to the Philippines in 61 im not sure yet how it got to Canada wearing its blue paint and spiraly plastic on all the cables but im turning it green again, the engine cases have been vaporblasted insides only as i want it to look like an old army bike when im done, just picked up the cyl today from the machine shop with new guides and valves and bored to the new piston, im painting it as i go along. still working on getting the correct crank bearings and still have to replace the gearbox ones, this site is amazing and i dont think i could do it without the knowledge and info contained in it from very helpful people, thank you for that
Hi Kevin...Good luck with it...You look like you have a reasonable bike as a basis for your restoration...You'll certainly get any information you need here and possibly parts as well...Have you found any 'novel repairs' yet?....Ian
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).
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).
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.
no novel repairs/bodges found surprisingly all in pretty good nick really Ian, i just had the cyl bored for the new piston plus new guides and valves, crank looks good so just the bearings and i can start putting it back together
can you decipher the brass plate info?
i read about the drain hole between the bearings in the cases but mine has 2 as seen in the pics
am i right in reading that i should plug them both and drill one new one up top
and also remove the crank nut and chuck the slinger plate? what happens if its left in place?
thanksKevin
OK, from my Key Card archives, 31YD94 was struck off the list on 31-07-1963 and had C number C5551221 on the petrol tank, frame number should be 1105**
bike was from contract S5209 which makes it a 1943-45 bike, so not 1939, unless the rebuilt plate doesn't belong to the bike?
It was sold by the army in Singapore.
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