The AJS twin has made slow progress in the last few months. It did throw a few surprises along the way as well. For instance, I found out that the engine cases were from a later model, someone had replaced them. The problem arises when you order parts all the way from the UK and to your disbelief, realise, it doesn’t fit this model. They made such frequent changes to the bike year on year it is difficult to keep track of all of it. As this was my first AJS twin restoration I had to learn along the way. But I finally managed to complete the engine and gearbox.
When I got the bike it had no clutch on it, only the empty tin primary cases fitted onto the bike and a clutch assembly separately packed in a cardboard box. And to my surprise it was not the right one but a 1930s model Burman Clutch. Burman and sons were based in Birmingham and made steering gear for Ford and Bedford trucks in the Thirties, and they also made gearboxes for British motorcycles such as Ariel, AJS, Matchless and Vincent. Matchless and AJS had the CP model gear box till 1951 and then the B52 from 1952. The CP model was mainly designed for military application and therefore was a robust, but, very crude design from the early Forties. Whereas, the B52 was a more modern design with a much smoother shift. Most pre-war and post war British bikes had a primary chain driven gearbox and the chain tension was adjusted by moving the whole gearbox backwards and forwards, which, though crude, was very effective. The whole assembly was encased in a tin case and held together by a single centre bolt and nut and an alloy band around it. Keeping the chain lubricating oil within this tin case was almost next to impossible on these bikes! Till they designed alloy cases, that is.
I had to source my clutch assembly for my bike from my friend Christopher in Pune. I know he has a whole warehouse full of bike spares. It needed a bit of repair work on the clutch basket where the bosses had worn out badly. I also had to fabricate a clutch centre adapter. I ordered a set of new clutch plates manufactured in Delhi from Ravi Motorcycles. Ravi Tuteja the owner of this establishment supplies newly manufactured cables, clutch plates, tank rubbers, throttle assemblies, exhaust pipes and a lot of other parts for the common singles of AJS, Matchless and BSAs. He has been my go to guy for sourcing spares for my singles and twins for a long time. I wasn’t surprised that the Lucas Magneto on the bike had no spark when turned over, so I handed it over to the very reliable Ruby Electricals here in Bangalore, an old timer and one of the last surviving specialists in vintage auto electrickery. As expected, Ruby did an excellent job. Though, I did have to source a newly manufactured slip ring from Brightspark Magnetos in the UK. Given Lucas’ reputation as Prince of Darkness, I felt they were very reliable if they were properly and regularly serviced. The workshop manual recommends a magneto service every 4,000 miles (6,400km)!
I have to now get a chain for the primary and cut it down to the correct number of links after which I will be left with the carburettor and ignition timing to work on. Exhaust pipes can go in after that and then I’ll be ready to fire her up. I am hoping that by the time you read the next column, she’ll be up and running. It has been a long wait!