Electronic ignition

Previously wrote:

The original points system is like going back into the dark ages. Electronic ignition gives the benefit of no wearing parts, accurate timing, a proper advance curve and easy starting. The Pazon system seems to get the vote for the best system at the moment as it gives accurate timing even when the battery is low.

Years ago, after setting my points timing as per the book, when I got to strobing the timing I found it was firing at 40 degrees before TDC (instead of 28 fully advanced) no wonder starting was hazardous to say the least.

Fit an electronic system, eliminate one more major source of poor running and enjoy the even tickover and good pickup.

It's strange that the previous owner spent money on the other mods but missed the most important one. The SU carb is an excellent mod but without an electric start to encourage the engine to suck, you may struggle to start unless you have a full tank of fuel. Once running IMO they are the best for engine flexibility and economy.

Thanks, yes I was wondering about the previous owner's priorities as well. But at least it gives me the freedom to choose and install the system I find best and gain some insight fitting it.

I was warned about plenty of fuel needed to get the SU going. It is fitted with a choking device, attached with a cable to a normal Doherty lever. But what puzzles me is which position is choke on and choke off? Its not obvious to me looking at the carb, but the cable operates a quarter moon disc connected to an axle,that turns 95 degrees from stop to stop. Any ideas? (the previous owner had forgotten, never used the choke?!?!).

Previously wrote:

Previously wrote:

Previously wrote:

The original points system is like going back into the dark ages. Electronic ignition gives the benefit of no wearing parts, accurate timing, a proper advance curve and easy starting. The Pazon system seems to get the vote for the best system at the moment as it gives accurate timing even when the battery is low.

Years ago, after setting my points timing as per the book, when I got to strobing the timing I found it was firing at 40 degrees before TDC (instead of 28 fully advanced) no wonder starting was hazardous to say the least.

Fit an electronic system, eliminate one more major source of poor running and enjoy the even tickover and good pickup.

It's strange that the previous owner spent money on the other mods but missed the most important one. The SU carb is an excellent mod but without an electric start to encourage the engine to suck, you may struggle to start unless you have a full tank of fuel. Once running IMO they are the best for engine flexibility and economy.

Thanks, yes I was wondering about the previous owner's priorities as well. But at least it gives me the freedom to choose and install the system I find best and gain some insight fitting it.

I was warned about plenty of fuel needed to get the SU going. It is fitted with a choking device, attached with a cable to a normal Doherty lever. But what puzzles me is which position is choke on and choke off? Its not obvious to me looking at the carb, but the cable operates a quarter moon disc connected to an axle,that turns 95 degrees from stop to stop. Any ideas? (the previous owner had forgotten, never used the choke?!?!).

The choke on the SU is conventional, i.e. you pull the cable tighter to get more choke. Take a look inside while you rotate the quarter moon part and see how more of the needle is exposed as you do this. I never used the choke anyway.The SU is great for economy as Dave says, but it has 2 flaws on a Commando. The first is a persistent popping of the engine when it is on the overrun. Some owners do not find this, but my SU did it all the time. Fitting Burlen's butterfly valve modification helps somewhat. The second, as Dave says again, is its reluctance to fill itself with petrol. You can stand there and kick for ages on a dry carb. before the bike will go.I got nearly as far as fitting a fuel pump before a second hand Mikuni came along and then everything happened first time. With current and future fuel prices though, the SU might come out again one day. When we went to the Norway rally in 2002 and had to ride for hours on a radar gun ridden 50 m.p.h. road, I got 99 m.p.g. out of an SU.

Thanks for the advice, I will wait and see how I and the SU carb get along! I am used to Amal on various other classic bikes, and know these instruments very well, and find them simple, reliable and quite durable as well, especially if fitted with an airfilter. So if the SU doesn't play along, I know the cure.

Previously wrote:

Previously wrote:

Hello, just wanted to introduce myself and ask a question! I just acquired a 1972 Norton Commando Roadster MkIV registered first in 1973. It has had a few mods over time, like primary belt drive and18" flanged alloy rims front and rear and an SU carb.It still has the original points ignition system, which I would like to change to full electronic.

Having looked through various posts in this forum and elsewhere recommendations seem to favour the Pazon system, sold by Norton Andover amongst others. Could anyone comment on this, like own experiences and things to look out for when doing the conversion. To me it looks straight forward, but I have learned over time,that this is when I need to be alert!

Looking forward to spring!

Hi Tom - I've had some experience of electronic ignition on Commandos (and other bikes) over the years - to date the best I've used is Tri-Spark. The Tri-Spark Classic Twin is available for Commandos - the best features are:-

1) The whole system fits inside the points cover (i.e. no separate 'black-box')

2) It has a very good 'anti-kickback' feature (very handy when kick-starting a Commando !!!).

It's not cheap though - - -

Cheers,

Thanks I will have a look at Tri-Spark. I am not too worried about kickback, being used to kickstart my 500cc single cylinder Matchless!