Tuesday, February 14, 2012

Lighting up the Journey of a Lifetime: BSA electrical system- BSA Build Progress Pt 4

  It's been a while since my last update, and I must apologize to my virtual audience for my tardiness in posting. The past few weeks have been rather hectic, so I am just sitting down now to finish out Part 4 of the Cannonball build progress. As a bit of a review, here are some of the things that have been repaired, restored, or updated on the bike.

  •   Upper and lower end of the motor disassembled, cleaned, and examined. New inlet and exhaust valves, top end de-coked, and reassembled with new components. Lower end blueprinted and reassembled with new main bearings.
  •   Carburetor found to be in good working order, spare Amal to be brought as well. 
  •   Gearbox completely disassembled and examined. New bearings fitted. Clutch and plates found to be in good condition, as well as all other internals. Oil drained and filtered, leading to replacement of kickstart gear.
  •   Frame and front end examined for stress cracks; none found. New bearings, bushings, cups and cones throughout. All components cleaned, greased, and reassembled.
  •   New tyres and tubes; rims and spokes in presentable condition. Front wheel received new axle and bearings.
  •   Brakes examined on front and rear- front brake relined, bearings cleaned on front and rear.
  •   Petrol tank removed and examined- mounting points in bad condition, leading to a new fuel tank being built.
  With all of these updates and repairs, the BSA build is going rather smoothly and is quickly approaching the point of completion. Now that the motor and gearbox are in better-than-new condition, thanks to the masters at Vintage and Veteran, one of the other major components to the bike is the electrical system. Now, in the same fashion as most 1920's machines, ignition on the 1927 BSA is provided by magneto. This eliminates the need for a battery, as most batteries of the time were unreliable in themselves. Common knowledge says that three elements are needed to power an internal combustion engine: fuel, air, and spark.

  Many of the riders on the pre-1916 Cannonball run had great difficulties with reliable spark. It seemed that just about everyone had at least one magneto failure on the trip. With this knowledge in mind, here's where my race bike sits. Early in the build it was determined that the BSA's magneto was providing sufficient spark, though was prone to open circuiting. To correct this issue, the mag was sent off for a rewind on the armature. A new condenser unit was added, and the pick up was converted to a modern style. Hopefully this should provide a consistent, reliable ignition system. However, after conversing with Ken Ashton (#26) and Mike Wild (#25), we all decided that it would be prudent to carry along at least one spare magneto per bike. During Cannonball 1, there was a team following along and rebuilding mags all the way across the US. Let us hope that Ken, Mike, and I are not in need of this service!

  I have also posed the idea of creating a shield for our magnetos. One of the big problems in Cannonball I was that most riders had mags that were exposed to the elements. After the first big rainstorm, guess what happened? You've got it---failure. Those lucky enough to power through were quickly searching for the nearest empty beer or soda can to create a small shield around the device. I'm wondering if it would be prudent to build several prior to the race, using light gauge aluminum or some similar material. Waiting to hear back from Ken and Mike. My feeling on the subject is to be as proactive as possible in determining possible scenarios of roadside failure.

  With the magneto out of the way, the other point to be discussed in this post is the lighting system. Now from the early 1900's to the early 1930's, most automobiles and motorcycles did not have electric lighting. Instead, these machines relied on carbide (otherwise known as acetylene) lighting systems. My readers may now be asking themselves: "Just how does that work?" So before I explain the plans for the BSA, I digress into a bit of history on these lighting systems and their mechanics.

Example of a lit carbide lamp

  Carbide lamps work on the simple process of burning acetylene gas. In order to create the gas, the lamp has an attached cannister (generator) with an upper and lower chamber. This lower chamber is filled with calcium carbide, while the upper chamber is filled with water. Water in the upper portion then drips down onto the calcium carbide, where it reacts chemically to form acetylene gas. The generator has a threaded valve on it to control the water flow rate, which then determines how large or small the amount of gas is that reaches the lamp and is lit. The lamp has an opening for the gas to enter, as well as usually a small wick that is lit by hand. Additionally, most carbide lights have a reflector in the back to project the beam of light onto the road surface. Light created by carbide systems is surprisingly bright--so bright in fact that many are still in use today by miners. The only downside to using carbide is that, once reacted, the material becomes unusable. Once this happens, the generator must be emptied and re-filled.

  Now while the carbide system does provide reliable light, I'm not very keen about having an open flame anywhere near the petrol tank. Were this event taking place in the UK or Europe, not having a light wouldn't be a problem. However American laws dictate that road vehicles must have a visible and functional lighting system. To ensure our bikes are legal and to avoid the potential danger of acetylene, Ken, Mike, and I will be using an LED set up. Our machines will retain the appearance of the original carbide headlight and tail light, but will instead be retrofitted with removable, battery powered LED lighting discs that will be rechargeable.

Jim Crain and his Cannonball BSA, Number 42
  Recently I spoke with Jim Crain (#42). Like myself, Jim is riding a 1927 BSA as well. His machine also has the carbide set up. Like Ken, Mike, and I, Jim is planning on retrofitting LEDs and installing a small gell cell (AGM) battery in the small pannier toolbox on the rear of his bike and running wiring through the acetylene tubing. Ken expressed his concern for failure on the AGM, so our three bikes will instead use the lead-acid type of battery. For my BSA, this battery will be located in the seat post-mounted toolbox, and should provide 20 hours of light. At the end of each day Ken, Mike, and I will recharge our batteries to be ready for the next day.

And that, ladies and gentlemen, is all for now. Hope to update more over the next few days.

Buck Carson
Confirmed Cannonballer #3
Carson Classic Motors Race Team

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