May 5, 2013
The OAS Rebuild begins at last.
OAS is my forth D3 Bantam, they’ve all been ‘56 or ‘57 swing arm versions. The first was a ratty old crate but just the thing for an engineering apprentice to learn something about bikes. After a couple of years it made way for a 100E Ford Pop. The second was also a bit dog-eared but gave good service for years until swapped for a BSA C11 project. The third was ‘RBD’ a perfect time capsule dragged out in the sunshine after 35 years encarserated in a coalhouse. RBD got the full restoration and was a lovely Bantam to ride but under the influence of a bad moon I sold it and deeply regretted it. Along the way I also had an Ex-GPO D1 and a B175. There was always a Bantam in one shape or other lurking in the corner of the garage but once RBD had gone I thought the Bantam days were over. Then sometime back in the summer of 2001, I went to one of those classic car and bike night get-togethers and bumped into an old mate.
“Are you still into Bantams?” he said. “I know a bloke in town who’s got one for sale but it needs sorting.” Two days later, there it was at the back of a garage under the dust sheets, a ’57 swing arm D3 intact and complete. There was a deal in the offing but with a catch. The guy selling had inherited it as part of his late father’s estate but he wasn’t interested in motorcycles it other than keeping the number plate to stick on his Triumph Stag. If I did the paperwork, got it through an MOT, transferred the plate for an age-related number it was mine for a 150 notes.
I had it on the road within two months. Mechanically it seemed to run quite well, some parts had been re-chromed, even the seat had been recovered. I bought a new rear tyre, battery and patched up the exhaust. It sailed through the MOT and Fawlty Towers DVLC gave it a new identity – ONR was now OAS. With that done I poked about in the engine. Someone had already been there! New seals, clean bore, new rings, everything was spot on. The only problem was the colour; a horrible leaf green like it had been put up against a wall and sprayed at point blank. What with a grey seat and silver painted wheel rims it was nasty in any case, green on a swing-arm D3?
“Definitely,” said the Triumph Stag man. “I’m dead sure it was green when my old man had it so I had a bloke give it a re-spray.
Back at the ranch I did a bit more prodding and probing hoping to find a trace of black, grey or maroon. There inside the fork shroud and front brake drum was the original grey. At that point I decided to hang any more work until the winter; instead I’d go out and enjoy it. OAS ran as sweet as a nut, brisk performance, lovely gears and good brakes even if it did get a few funny looks at various old bike meets. (Blurry picture of OAS on a VMCC road trial with slip-streaming snail)
Autumn came and I found myself ‘between jobs’. I was doing contract work at the time and couldn’t find anything going save a job that wasn’t due to start until after the following Christmas. There I was with an eight-week enforced sabbatical on my hands and no income. So I sat down and scrawled out a book about the BSA Bantam (a story in itself). In case you are wondering, OAS is on page 169. The young lad in the picture never did get to ride the Bantam but he did go pillion on the back of my Moto-Guzzi a few weeks ago when we had a day out at the Classic Bike Show in Stafford. We looked in at the Bantam Club stand and elsewhere and it’s thanks to him that I’ve come out of Bantam hibernation and decided to get OAS back on the road in something resembling its correct colour scheme.
It’s ten years since OAS last made smoke and the book was published. The D3 has been taken to pieces, bagged, boxed and labelled up for the promised restoration but other commitments, work and a house move stopped the project in its tracks. Now I’ve re-opened the boxes only to find some pesky little rodent had got in and chewed up the bags, spilling their contents into a jumble. (See picture showing the jumble laid out on the deck) Whilst I dither over the painted parts I’ve started working through the bits that need repair or replacement. More next month……
September 3, 2012
I really like the grey colour. Long ago, when we all rode Bantams as our only form of transport, my friend had a Plunger D3 in grey and I had always assumed it was a Plunger colour until I found out recently that it was used on SA D3's as well.
It's nice when there is a background story, and as the 'star' in print, it deserves the best treatment! Can't wait for the next instalment
I'm not a complete idiot ............................................ some parts are missing.
My old D3 SA was Grey with a nice cream panel on the tank ... a friend had put two parallel dark grey lines (by hand it was his trade) around the cream panel and single ones on the guards and other cycle parts... just to make it different ... so IMHO Grey is the best colour ... could be biased I suppose
Looking forward to next instalment
Good to see you on the forum, I think the 150's are a good combination for a Bantam too having a 150 barrel/piston/head on my D1, completed a 210 mile run this sunday on mine with no problems.
Excellent book by the way.
BSA Bantam D1 "150" in use regularly often as general purpose transport, quite a few other bikes as well. Cornwall Area Rep.
May 5, 2013
The second Installment of the OAS Rebuild saga.
After a little deliberation I’ve opted for the lure and durability of powder coating. Taking into account the time scale and cost to turn my garage into a spray booth let alone hiring the equipment I found a company just around the corner from where I work who got the job done in a matter of days. If you’re in reach of Loughborough then go and visit Charnwood Powder Coating. The offer a friendly service including iron filing blast which efficiently removes the paint and not the metal. If, like me, you’re on a budget, pick a standard colour. I chose a RAL7039 – Quartz Grey (go to ** Please log in to view **). This was close enough to the original grey found on a few parts that hadn’t been covered by that horrible green (rejoice, it’s gone!) The other advantage of using a standard is being able to get a spray can for doing the bolt heads and other touch up parts. Again I found another local company, Granville Supplies who will mix a spray can of polyurethane whilst you wait. For the tank panels I’ll be going for a can of RAL1015 Light ivory and the legshields , yep I’ve got those as well, will be black.
Whilst I’m not exactly setting out to do a 100% exactly as it left the factory restoration (and how could anyone know) I’ve set myself a few standards.
- No infestation of metric threads. I'm in trouble here already, I've used a M6 & M8 fixings for the mudguard... I will endeavour to work in good old chains and furlongs
- No plastic tape. I might have to take the wiring loom apart, it's held together with black plastic tape. I suppose I could cover it with shrink-wrap?
- No plastic cable ties. I've got a sheet of neoprene rubber, made a template and starting cutting out ye olde type rubber cale ties.
- No red shroud electrical connectors. I’ve bought a bag of old type bullet connectors,
Before I commence with the re-built, a few things that cropped up along the way.
The centre-stand is one of the main-bug-bears of owning a Bantam. The feet wear out quickly rendering the said device completely useless if not dangerous. I took a piece of bar, sawn a flat and welded to the base of each leg. The result is a far more robust and sturdy stand. That should last a while.
The foot-peg bar was well and truly worn out, bent and just generally knackered. With great reluctance I’ve binned it. It would be easy to get hold of a 12mm length of BDMS and die M12 at each end but no, I’ve done it the hard way I’ve turned down a length of 16mm dia bar to ½” and thread cutted BS Fine just as some capstan lathe operator lurking in the dark bowels of a BSA factory probably did in the 1950’s. I'm inching my way out of Metrication and two-fingers to Brussels! In any case, the various foot-peg collars are too loose on 12mm and I can retain the original castle nuts and new split pins.
Finally, the plates at each end of the bottom bracket were chewed up, so I cut the remains of the old ones away, made new and welded in position. By eck, that's better.
The benefits of having a lathe are many. A new footpeg bar c/w BSF threads in the making
How's that for a centre stand mod.
Bottom bracket end plates fashioned and welded
Man and Bantam in complete harmony...
More next month.
November 23, 2011
May 5, 2013
The Third Installment of the OAS Rebuild.
Thanks to getting chucked off my Guzzi and the resultant road-rash and bruising, the OAS rebuild programme has slipped a more than a little. The plans to have it up and running for mid September have crashed and burned. At the last shout we had most of the frame built up, the forks and swing arm went together without a hitch. I even managed to put the steering head together without loosing any of the 48 little 3/16” dia balls. Then I didn’t like the look of the swing arm rubber-bonded bushes so decided the rear section had to come out again. After fifty-something years the bushes were in a state and the powder coating process can’t have done them much good either. I got a pair of new ones from C & D Auto’s though I dare say you can get Metalastic products from other sources.
To get the old bushes out you need a session with a junior hacksaw. Clamp the swing arm in a vice with some rags to protect the paintwork. Make two cuts through the inner sleeve at 90 degrees and then chew through the rubber section until you hit the outer sleeve. With something like an old 3/8” wood chisel, tear out the rubber leaving just the outer sleeve. More gentle sawing if necessary, checking the depth of cut for evenness until it nearly through. Soak the sleeve in WD40 and use a punch to see it starts to move. Maybe a bit more sawing is needed but take care not to touch the swing-arm bore. Once the old bushes are out, clean off any burrs and set the S/A and new bushes up in a vice with washers either side and in contact with the vice jaws. Before pressing the bush home check it’s straight and a spot of Loctite won’t go amiss. The bushes should be a tight fit. I got by with a 3 ½” vice but I’d recommend something larger. I had to put an extension tube over the tommy-bar. Anyway, job done. That should last another 56 years.
The only way to get the old bushes out was to hack it...
New bushes acquired from C & D Autos
Pressing the new bushes home
Next up was the wiring. The old loom was a bird’s nest of frayed wires and sticky-tape so I dumped the whole lot and decided to make my own. I took a tip from another Bantam Owners Club forum thread and got hold of some seven-core trailer cable and some shrink-wrap sleeving. Cut back the cable outer sleeving and you get black, white, red, blue, green, yellow and brown. Re-wiring the headlamp switch was not that difficult. Snip the old wires off, gently prise back the outer light blue shroud and make a note of what went where (or take photo). Use a soldering iron the remove the old wires and as much solder as possible. The copper connectors will pull through the rubber body. I used a small blow-torch to remove the rest of the old solder and then pickled the connectors in a jar of battery acid (H & S can have a fit on me). Re-assemble by pushing the connectors back through the body. Use plenty of flux and re-solder the new wires. Substitute translucent for white (a slightly heavier wire for the frame-earth connection) and pink for yellow (feed to dip-switch). From the old loom I salvaged most of the bullet connectors so any modern red-shrouded connectors are limited to the also modern rectifier and kept out of sight.
The headlamp swiitch now re-wired
Even though I’d owned quite a number of Bantams including swing-arm D3’s, I couldn’t remember or figure out where the horn and rectifier were supposed to live so I’ve opted for the bracket that comes off the chain guard. This keeps the two devices behind the left-hand panel and easy to get at without being too obtrusive. Before the rebuild the rectifier was inside the toolbox but I didn’t like the idea of it being cooped up inside a box and liable to damage from a tool-roll bouncing around.
One more bit of frame fixing left was a new dual-seat bracket. - The old one had bust into two-pieces but came in useful as a pattern. A new one was fashioned out of a length of 1” x 1/8” flat.
New seat bracket, ready for painting
Now it’s back to the Guzzi which also has a bit of road-rash. I think I’ll stick to Bantams.
More next month….
September 28, 2011
November 16, 2011
Hope you`ve recovered from your spill...a tranny van helped separate me from my old Le Mans OPP129P in `85.
I was looking at your avatar and thinking, that`s familiar.Then read on,dug out your excellent book and there it is on page 6!
Very much enjoying following the refurb.I like the grey colour too.
May 5, 2013
The fourth Instalment of the OAS Rebuild saga.
Yes, well, "more next month" became six years! You name it..... family and domestic bliss, home improvements, kids getting married, a Morris Minor rolling resto and a spell in hospital to have my hydraulics restored. Well hey, here we are again, and the dust sheets have come off for a determined last push to finish the Bantam and make it smoke.
Firstly, finish the wiring. I merely replicated what came off but then noticed that the lighting switch has 9 pins (see previous picture) with a translucent wire going to earth. This doesn't appear in any workshop manuals as far as I know and I'm certain it's original. Over to you experts. I've checked it out with a meter, and everything seems to work short of getting a battery and trying it out.
Leaving the electrics alone for a while, a couple of years ago I did set about improving the fuel tank. Before the bike came off the road yonks ago, I'd fitted an in-line fuel filter which seemed to fill up with crud. The tank inside didn't look too bad, maybe some loose rust lurking about. The tank was also bit pock-marked, so decided on a bit of belt a brace to make sure this tank won't cause any problems in the future. One way of getting rid of rust is black treacle. Buy a tin of from Supermarket and bury at the bottom of shopping trolley so the one who pays the bill doesn't notice. Mix in hot water to help dissolve and fill up the tank. Go away for a couple of days. Empty tank and let it dry in warm place. Take a peek inside and it should look nice and clean. Don't use golden syrup, that for pancakes. Next, a tin of fuel tank sealant. I used POR15 silver resin. It cost £22 but worth it. Follow instructions on the tin especially the swishing about on either side. Inside of tank now very clean, smooth and with a strong resin lining.
Will try and send some pictures soon.
More in five years' time?????
April 29, 2015
January 9, 2013
The Only Bantam with a RESISTER in the lighting circuit was the Lucas equipped bikes
January 9, 2013
The Wipac Resistor Kit was an after-market add-on never fitted at the factory and was for early AC only bikes
to allow use of a Stop light, so of no relevance to this thread
Lucas was the Only one fitted with a lighting Resistor as standard
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look at BSA service sheet 808E page2 it shows the same wiring diagram as the one above
January 9, 2013
from August 1956 the D C circuit had a RESISTER and EARTH wier in the LOOM at the switch soket for D 1,3and 5 ,,, not shown in the dyagram above this dyagram is on page 81 of the Haynes manual and not for use on the D 7 modles as stated
very sorry Owen ,, Mike and I seem to difer on this earth wier at your swith soket going by my WIPAC info sheets ect and WIPAC [ NOT bsa s ] wiering dyagrams and the fact my owne D 3 & D5 & anuthers i worket on have a resiser in cerket you will find it under the tank i was trying to tell the readers so thay can upgrade the wiering away from the resister and that the wiering dyagrams are not allways corect as i posted
we are looking forword to the rest of you photos and post thank you for a good job
September 24, 2018
August 1956 dc circuit clearly show a resistor in the loom.
Interesting I stand corrected
Never seen that DC diagram before, the resistor reduces the charge to the battery when all the lights are off
the Translucent wire on the switch(above)is connected to the resistor
if you are making a new loom from trailer cable wire what will you do about the resister wire im guessing it must be about 1-2 Ohm
wonder if any of the replacement looms have one fitted
The switch has 10 internal connections but 9 external pins
10 is connected to 2 internally
do you have any more original Wipac wiring diagrams for the early bikes
like the D7
the diagrams on the Net never show the coil wiring to the stator pinouts and although the stator may have a Spec no you cant presume that the coils have not been replaced sometime in the last 50years
the later ones D10 on are fairly straightforward to follow
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