Hi all,

I'm new here, so let me introduce myself:

I'm Andy, I live half the time in the UK (Macclesfield) and half in the Netherlands (Den Haag). I recently decided to return to motorcycling after a 25 year break, during which time I have been playing with cars and 4x4's. In my youth I was an enthusiastic brit bike rider, and had a number of BSAs including M20, M21, B31, A10. The bike I liked best of all was an M20 with girder forks, so I decided to invest in another. I recently bought a pre-war M20 that was discussed on this forum a while ago. Some pictures are here:

http://photobucket.com/BSAM20

The bike has an interesting story. Apparently it was found in a barn in Austria by a parachutist who spotted it through a hole in the roof. The farmer said it had "belonged" to his grandfather who must have acquired it during the war, hence pillion seat and rear light. The parachutist bought it and put it in a pizza shop where it remained for some 25 years before being spotted and bought by Bas from www.classic-motorcycles.nl who kindly sold it to me.

Because of the beautiful patina and great story I don't want to "restore" it, just get it happily running and safe to ride.

The bike runs fine, but the forks were completely knackered having been broken at some stage, and the bushes totally worn out. I've sent them off to Jake Robbins at Vintage Engineering in Hastings who is currently repairing them. It also needs some wiring and the rear wheel bearings are knackered but apart from that there is not much required to get it on the road and through an MOT.

There are a few things I need some help with, if you guys don't mind giving me some pointers:

-> There are many places selling spare parts for M20's and several are listed in the links on this site. Is there one place that you can recommend as having a comprehensive stock of good quality parts? Or do I need to shop around every time?

-> I need to replace the steering head bearings. Can you get caged or taper roller bearings to fit these days or am I still going to get covered in grease and spend ages crawling around on the floor looking for dropped ball bearings?

-> what's the best place to get rear wheel bearings from? What about assorted cycle thread and BSF nuts, bolts etc?

Also, can anyone provide any more information regarding the date of the frame KM20 478 and engine M20 54510? The tank is chromed, is that likely to be original or would it have been painted from new?

Any help much appreciated, and thanks in advance.

email (option): andy.haxby@gmail.com

Hi Andy and welcome to the forum now you have put your head over the parapet! ...In answer to some of your questions...There is no 'one stop shop' for all your M20 needs. Russell Motors in London probably still hold the largest stock of original bits and pieces but other dealers in the UK have some as do some in the Netherlands..Draganfly have a good stock range but less original stuff as do C&D Autos and other UK BSA dealers...You do have to shop around.
Carbs, magnetos, dynamos, regulators etc. are provided for by more specialist dealers...
There is a replacement steering head bearing kit...Sealed ball bearings as fitted to Norton Commandos, Buells and others I guess as standard.
I can provide a kit if you need it..mail me off forum for that.
There is a modern equivalent for the rear wheel bearings so these (unlike the fronts) can be sourced cheaply from any good bearing factor..Number is 30204 (taper roller.)
Most of the threads on the engine and gearbox are either whitworth into aluminium or cycle thread into steel. There are some exceptions such as the cylinder head bolts (3/8" BSF), the crankcase oil unions which are also BSF at one end, the primary chaincase screws etc. The chassis is largely cycle thread though this occurrs in the 20 TPI form for some applications..
Carburettors, speedos and electrical equipment are generally BA (as they are classified as instruments.
Threads on these old bikes are very mixed with all sorts being used for different applications. There are even metric bearings and fittings with metric spanner sizes...even though it was a fully Imperial 'standard' system at the time.
There is some thread information (and bearing information) on the 'Technical Section' of this site.
I tend to use all stainless fasteners...not to everyones taste I know...so consequently I can't recommend anyone for plain steel types. No doubt someone on here will make some recommendations.
Basically though you can take advantage of this forums greatest asset when you have a problem...the huge amount of combined knowledge available....just post the question!....Ian

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

Hi Ian,

Thanks for the swift and helpful reply. Email on the way regarding steering head bearings.....

email (option): andy.haxby@gmail.com

Welcome, also if you need a local (ish) workshop up north you can also contact Dave Plumb.

Just get it ready for June 2014 :-) We'll see you on the beaches.

email (option): kit247@hotmail.com

Andy Welcome, Ian our mentor, has said it all,good luck with the rebuild, andrew.h

email (option): warbikes@gmail.com

Hi Andy, welcome to this wonderful forum, I discovered it 2 years ago and it helped me a lot, also the search function is very handy to dive in the archive.

Nice pictures, I have seen it for sale on Bas his website, also nice to have a story with the bike, it gives the bike even more character.

I think you KM front frame is late 38 or very early 39. But I doubt if the front frame is original as I can't discover a lot of prewar parts on the rest of the bike. So my guess is that the front frame has been replaced at some time. Think the bike looks more from 1941/42 period and maybe the engine could be original. Hope this is not disappointing to you but it will make it easier to replace the front frame with a sound one....

I have a 1942 M20 and Henk provided this picture:



Good luck and lots of fun with the rebuilt,

Michiel / Netherlands

email (option): m.wijbenga@hotmail.com

i have seen the bike it is a beautifull bike with a history with low cost to complete it the handles on the bar are not the good ones and some other small things you must keep it in this condition and you ride a great bike Gr Theo

email (option): oldbikes@kpnmail.nl

Hello and welcome to the site

I am still in the newbie catagory myself but I can certainly vouch for the amazing wealth of knowledge on here.

I hope your build goes well. My forks are with jake also, so lets see who gets them back first

Darren

email (option): dwrudd@lineone.net

I'm located half way between Chester and Birkenhead, just a couple of minutes off the M53, I keep a stock of zinc plated steel cycle thread nuts and a few bolts in stock. I can probably help with other things too, my contact details are on the links page (Dave Plumb M.E.S.S.)

email (option): davmax@ntlworld.com

Hi Andy,

Welcome to the forum!
Just like with Michiel, this forum helped me much as well.
Bas is a good friend of mine, I posted this on the forum a while ago;

http://pub37.bravenet.com/forum/static/show.php?usernum=3155626639&frmid=16&msgid=1236979&cmd=show

perhaps it might help you.

Regards,
Sven

email (option): snvosselman@gmail.com

welcome andy if you want any information about certain bit just put what you are wanting information on in the search box top right ie wheelbearings load of information from people on the site pops up also tec info has got load of information

Thanks again for all the informative replies.

Apparently my bike (or at least the front part of the frame) was delivered direct to the war office in 1938. I'm not really bothered if it is a collection of bits, any vehicle of this age is going to have had a variety of running repairs particularly if it went through the war. It's more interesting for me to see how it ended up now rather than re-create how it started out life, so if parts of the bike are 41 or 42 who cares.

I guess when it gets registered on UK license plates it will still say 1938 as they go off the frame number. (Incidentally, I joined the BSA owners club at the NEC classic bike show last week, and they told me that to get it registered in the UK I will need to take a pencil rubbing of the frame number, rather than a photograph, which I find interesting).

I am curious though, what bits give it away as being later? I already figured that the speedo drive is not pre-war, but what other parts? I'm also curious about the chrome tank. Were early WD models supplied with chrome tanks or is this tank off a later civilian model?

Cheers,

Andy.

email (option): Andy.haxby@gmail.com

Andy when i saw the BSA the backframe has a welded lug for the side field stand i think it was only for army bikes. Bud in 70 years is so much repaird or changes and every detail hase a story to tell. even some litle spares who where changes tell some storys some are realy interesting. Gr Theo Schipper

email (option): oldbikes@kpnmail.nl

Hi Andy,

Here is a picture of a KM20 from 1939



If you compare this to the 1942 picture posted earlier, there are lots of differences, most obvious the larger tank and valanced rearmudguard, but also lots of small details: rubber footrests, speedodrive in frontbrakeplate, narrow toolbox, inspection hole in timingcover, a machined groove for a rubbercover over the clutch arm in the gearboxcover. front numberplate, etc

But also the rearframe has many small details which are different. like a forged lug below the frontengine plates, where the later frame has the tube flattenend. a lug for a small sidestand just below the rearbrakepedal pivot. 2 small threaded holes just in front of the saddle spring mounts. Sidecarlug in front of rearspindle. No braced on lug for the fieldstand (the early fieldstands were clamped).

Just compare the pictures and you will find them. This is why I think your bike looks like a 1941/42 one. In this period the fieldstandlug was braced on and it still has the large 8" headlamp like yours. The tank, rearmudguard, footrest, rearframe is correct, even the engine could be correct.

I totally agree with you that all the changes during it's life has it's charm and there is no reason to correct them but as your frontframe is in need of some serious work (retubing) I would consider replacing it. Later WM20 frontframes are not hard to find, it is the rearframe that is rare.

Don't know the situation in Britain but it is very easy to get new papers with a motorcycle in the Netherlands, so as you live half your life in Den Haag maybe you can get Dutch papers with it and then export it to Britain??, just a thought. Or just ride in Holland of course !!

Don't get me wrong just trying to help you considering the options. Hope it helps. Good luck !! Michiel

email (option): m.wijbenga@hotmail.com

Hi Michiel,

Excellent, thanks for your help.

I'm going to print the pictures out and spend the weekend studying them and my bike :-)

Cheers,

email (option): Andy.haxby@gmail.com

Welcome to the forum Andy
I've spent ages studying the differences in photos when I was finding parts for my 16H. I still ended up with some parts which aren't technically correct for the year, it just depends how picky or exact you want to be. All the original "in service" pictures I've seen of bikes from the same contract as mine are different to each other. Once the bikes were in service they were swapped about with any parts available. The objective with a lot of people on this forum is to get the bike to factory spec for the year, which is a good point to aim for. I've even ended up with the "rivit counter" bug, but the main thing is to get the bike on the road and enjoy it. You can alway change parts when and if they turn up (and if you want to pay some of the stupid prices for things).

Good luck with it Andy, it's a great bike

email (option): horror@blueyonder.co.uk