500 electronic ignition

[MickeyMoto]

I managed to kick start the bike first kick, even in my parlous state. The only kick back was when i turned on the ignition and the plugs sparked and it burnt off the remaining fuel in one of the cylinders, but not a huge kick back.

The board has a red light which is on when the cut out is in the way of the trigger and off when the disc first comes 'into sight'.

I set PMS1 on the compression stroke and move the disc so the trailing edge of the cylinder 1 cut out turns off the red light then tighten the nut. Simples.

I had to remember that the cam turns anti clockwise on the left side.

[Steve Brown]

That's a shame. Is the ignition still on the bike, or did you change to something else? I've not double checked mine with the strobe yet, but it does at last tick over again and when I took it out on the motorway yesterday, it's found another 10 mph from somewhere and will rev pretty much to the red line in top, so it can't be far out. The curve for the 250 turned out to be the same as the 350, so the system wasn't modified in any way.

I took the circuit board to the pub before I fitted it to show to a friend who was an electronic engineer by trade and worked on electronic ignitions at some stage. He was very impressed by the build quality and said it's using a standard Motorola automotive timing chip, which is apparently a good thing. I was intrigued to know how it could work with with one sensor for two cylinders given the uneven timing intervals. He said it initially calibrates itself by calculating the relative time between the slots passing the sensor, so it knows which one is for each cylinder. I wonder (and it is only a guess) if it struggles to do the initial calculation if the engine doesn't turn over a few revolutions at a good speed? I'm not sure I've ever seen a Camel in the flesh, but looking at a picture, if it's anywhere near as awkward to kick over as something like a Bultaco, maybe that's some of the problem?

I'll be interested to know how the Strada performs on it's test run.

Hi Barry, I sent it back and was refunded immediately so no complaints there. What you describe sounds slightly different to what I had. I can't remember just one sensor for two cylinders for example. It is a while ago now. I was trying this on my 350 Sport and did try for some considerable time. I'm not a novice mechanic but still found the method for adjusting the timing to be extremely fiddly and time consuming. Especially when it seemed impossible to get it right. Your results sound to be spot on! As you said, easy starting and idle plus a max power boost courtesy of strong accurate ignition-everything I was expecting! My 350 now has a standard (ish) set up of blue Piaggio CDI and a black pick up. Dead easy starting and runs spot on too. My Camel was being a bit moody lately so I fitted blue scooter CDI to that as well, and hey presto that now wakes up readily too! Kick start is still high though and I am getting shorter!

[Steve Brown]

It'll be a while yet, I am recovering from a tendon operation and can't get my foot on the foot peg, although things are improving.

Steve, I agree with the rotor problem. It would be better to use the existing key on the cam and slot the circuit board. The ease of getting the timing correct (set pms1 on compression stroke and turn rotor until red light extinguishes) but holding the rotor whilst tightening was a problem.

I have not tried kick starting, as I cannot get a good swing whilst loading my bad leg on the floor. I'll give it a go tomorrow.

Keep up the recovery Mickey! It's good that yours starts easily too. My first fitting of the SWF kit was very encouraging too. Easy starting and 100% reliable idling/pick up. It was as flat as flatulence when ridden though, so I tried to adjust using a strobe and it all went downhill from there. If I got max advance right then starting was only possible with a bump start down my steep driveway, along with poor low speed running. We tried 2 circuit boards with the same result. Ann gave lots of advice and tips but when he eventually said it was me having difficulty kickstarting I decided to give up. OK, he couldn't know I have the legs of Popeye and spinach every day, or that I normally start my Pratt and Whitney special with my little toe, but still, eh?

[MickeyMoto]

Legs of Popeye and spinach every day?

Do you stir fry them and serve with a sauce?

I'll get some photos and me coat

The first photo shows the circuit board and the rotor at TDC (approx) on Cylinder 1. It is timed to the trailing edge of the cutout on the compression stroke.

The second shows the coils and the grey wire to the tacho connection.

One thing to note is that I have used the washer and the nylon from the original system. The SWK comes with a new M7 nut and washer. The washer was not deep enough to alow the nut to tightened down on it, instead it tightened to the end of the camshaft. The nut was a plain nut, too, and I wanted a bit more security than that.

[Steve Brown]

Mickey your rotor is different at least-I can't say about the circuit board except to say I'd still prefer that to be adjustable. He must have upgraded it a little. Keep us posted on how it performs longer term-Barry too please!

[BarryCambs]

Thinking about it, I seem to remember Anne saying the original version had Hall Sensors and the optical trigger is a later modification. I don't know how recently the sensors changed?

I was out with friends yesterday and did 180 mile round trip to Norfolk. The bike performed beautifully (in spite of being 40 years older and 1/4 capacity of most of the others), but I have been warmer! People telling me what a difference heated bars and saddles makes didn't exactly help lift my mood.

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The 250 has a mechanically driven tacho, the square end of the cable sitting in the special nut. This is the first time one of these has been fitted to a 250. Originally, the bike didn't have any fuses, so I took the opportunity to add a couple while I was fitting the new regulator/rectifier for the 12v conversion. A friend recently had a fire on his Guzzi when the regulator went short circuit, so I have fused that as well.

[MickeyMoto]

I had problems on Saturday. The bike started but wouldn't rev past 4 or 5k depending on wind direction.

Checked the carbs and one float was set to 18mm. Today the bike revved past 8k, pulled from 2.5k in top and started easily. In fact, brush the button and the engine starts, no long cranking sessions.

So far, so good.