Saturday, 21 March 2015

A100 Restoration: Electrical Investigations

The date of the inspection draws nearer and I've checked most of the items on the list. Brakes seem good, a new chain and sprockets are on the way, brake lights work, signal lights work, transmission works, etc.

The one thing which I am seriously worried about at this point is the headlight circuit. As it stands, the headlight only comes on VERY dimly when the engine is running. 

Free Wiring Diagrams - Suzuki A100 & AX100

I managed to track down some wiring diagrams from online sources and also from the Haynes Manual I purchased. They are provided here just in case they are of use to someone else.

After examining the wiring diagram and getting some insight from a person on advrider I came to the conclusion that the voltage regulator was faulty. Funny thing: if you look at the Haynes diagram, the regulator is actually not shown.

Electrical Engineering with Tom

Back in 1975, voltage regulators were simple. This particular one is constructed with a resistor an a zener diode. It is called a shunt regulator and the diagram is more or less like this:

Vs represents the output from the magneto. Vs on the bike is alternating. Dz is the zener diode. R2 represents a headlight. 

Here is my super simplified explanation about what is going on: The zener diode is a diode in reverse. Basically, as the voltage across the zener gets high enough, the zener will go into breakdown, allowing current to flow across it such that the voltage across the zener is fixed to Vz (in this case it should be  ~6V for our headlights) 

It is important to note that the zener still acts as a regular diode in the other direction, so when Vs goes below 0V (is negative) the output will be clamped to a maximum of about 0.7V. Here is what we would expect the input and output functions to look like if everything were ideal:

Note that at its peak, the engine is outputting Vs_max (probably ~18V or so) and Vz is about 6V. Youmight ask, where does this voltage go? It is actually lost over R1 such that VR1 is Vs-Vz when Vs is greater than Vz. Also note that the zener does not come into effect when the Vs is between -0.7V and Vz.

In any case, I believe that the zener on my bike is faulty and actually breaking down much sooner than 6V. My suspicions seem to be confirmed by multimeter readings of about 2V across the headlight when idling. I've since ordered a new zener diode with a Vz of 6.3V from someone in Florida. 

My backup plan to pass the inspection if the zener does not arrive is to omit it so the voltage will be unregulated. I pulled it and started the engine in the garage and the headlight lit up very brightly indeed. The only concern is burning out the bulb.

Monday, 16 March 2015

A100 Restoration: DMV Hell

Alberta registries are a racket.

The chap who sold me the bike claimed it had never been registered and I hoped this would mean it would not need an Out Of Province Inspection (OOP inspection). When I've bought bikes in the past I always:

  1. Bought insurance
  2. Went to the registry with said insurance and registered the bike
In that order. So that is what I tried to do. I contacted my insurance company (big shoutout to Touchstone Insurance for the best rates/service I've come across in YYC) and got hooked up. 

VIN History with Tom

Ok, so I had to take a guess at what the VIN of the bike was. You see, VINs were not actually standardized in Canada until 1980. Obviously the guy who sold me the bike had no documentation as he didn't even think the bike had ever been registered. The number stamped on the frame went something like: A100-XXXXXX. Obviously the first part is the model and I learnt that the second part was likely just a serial number indicating which number off the line this bike was. Modern VINs have 17 characters which tell you all kinds of things about the vehicle. I provided the whole 10 digits to the insurance company, who issued me a temporary insurance doc and told me they needed the registration ASAP to keep the policy going. The Alberta Registry I went to (our version of the DMV I guess) was unable to enter the full 10 digits as their computer system rejected the format. They just went with the 6 digits and left it at that. Oddly, they told me that the bike had been registered in Quebec. I suspect the number they found was actually some other poor chap's bike (as it is possible with these old VINs that you will have a duplicate VIN belonging to a different make and model). But I was exhausted from arguing with the registry people so I decided to just take what they were offering. 


Annoyingly they did say I'd need an OOP. 


Now I actually have to get this bike road ready before I can register it. The permit to get the OOP was about $20. The OOP is a thing you need to get done if you have bought a vehicle from out of Alberta. It involves getting a professional mechanic to look over the bike and deem it safe or unsafe for use on AB roads. I have heard a lot of horror stories of mechanics nitpicking tiny windshield chips or body rust on these thing when people have got their cars inspected. 

The trouble is, the mechanic can charge whatever they want for the inspection knowing full well if they find something you probably will just pay them to fix it to pass the inspection. Talk about a conflict if interest. I asked a friend for some advice on where to go and he recommended a shop here in town which he reckoned would be fair with their evaluation. I chose this shop over other (cheaper) shops based on his recommendation. I booked myself in for the end of the month to give myself a bit of time for some maintenance.

I did manage to find a document which says what they will check. Click here if you are interested. The good stuff starts on page 35.


Clip of the ol' girl gurgling away in the garage - at least the engine seems to be in good nick. She's obviously lacking in the electrical department hence the lack of headlight.

P.S. Also bought some parts, an owners manual and a service manual. Will update when stuff starts coming in!

Friday, 13 March 2015

A100 Restoration: A New Project

Welcome to the first post in what should be an excellent and most triumphant motorcycle restoration series. I've fancied doing a restoration for a while after seeing these guys at the Calgary Motorcycle Show a couple years ago and now I have my chance.

The Vision:

I saw the bike come up on Kijiji. It was in Saskatchewan and the chap said in an email that it had never been registered anywhere. From my research online, it appeared to me that this would mean it would not need an out of provice inspection to register in AB (more on that later). So a road trip was planned to Shaunavon Saskatchewan which is 5 hours away from Calgary and in the middle of nowhere. After many miles and a couple Tim Horton's coffees we arrived to find a treasure trove of old bikes in a workshop. Turns out that the guy was a retired oil guy who loves restoring bikes. The A100 was going to be his "going to coffee" bike but he had picked up a new bike which he liked better. I do not know how he decides which bike to work on each day as he seems to have about 10 on the go!

The Workshop
The Bike:

The bike was in decent shape cosmetically and mechanically. Obviously it needed a good painting and some dent filling and probably a bit of mechanical work. The chrome was in great shape and their was very little rust on the frame. Overall, everything was there. He fired it up on the first kick - a good sign. Blue smoke poured out of the exhaust pipe and into the chilly winter air. Satisfied, I paid the man and headed home with my prize. Total purchase price: $1000.