Commando race ignitions

Fast Eddie

Fast Eddie

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What sort of ignition systems are you track riding boys running, and what are the pros / cons about your individual set ups ?

For clarity, I’m askimg about total loss or self generating systems here, that do not use the stock alternator and rotor.
 
Grant wrote an article which may be of interest:

Norton Commando Wiring Diagram – total loss (race bike)

"It’s not at all uncommon for a race bike to run total loss electrics (i.e., a freshly charged battery is connected up at the start of each race, and there is no provision for charging on the bike)

The mass of the rotor on the end of the crankshaft and the magnetic resistance as the rotor spins inside the stator has a cost of about 1% power output..."

granttiller.com

Norton Commando Wiring Diagram - total loss (race bike)

Michael Scott reached out to the Norton Commando Facebook group, as he had a query about a bike he has recently picked up. He explains that the owner recently passed away, and this race bike has been…
granttiller.com granttiller.com
 
This should be an interesting post. The goal is an ignition that goes to full advance at around 2000 RPM. That's the "Holy Grail". Many racers just use fixed advance and a rear wheel starter. You don't want any retard on the track. I had to use resistors in the wiring of my EI to get rid of the low RPM retard.
 
The only currently competitive Commandos on the UK race scene that I'm aware of run crank-mounted Maney kit with Boyer electronics
 
B+Bogus said:
The only currently competitive Commandos on the UK race scene that I'm aware of run crank-mounted Maney kit with Boyer electronics
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Name that currently competitive Commando! In fact, name that currently used race Commando!
 
SteveA said:
Name that currently competitive Commando! In fact, name that currently used race Commando!
Click to expand...
I know that Tim Horton still campaigns Gary Thwaites old 1007 Seeley.

Dunno what ign he uses tho…
 
B+Bogus said:
The only currently competitive Commandos on the UK race scene that I'm aware of run crank-mounted Maney kit with Boyer electronics
Click to expand...
I ran that set up in testing. But it didn't survive, so I used the same box with the short advance curve and a cam pick up. Actually I think it ran well, I had no reason to change things other than general annoyance at Boyer pick up connections and a suspicion that the advance curve might not be ideal. Only after changing did I feel that, in fact, the advance curve wasn't an issue at all. I was setting it on the strobe to fully advanced at 5000 anyway, and starting on rollers.

Then I changed it all for a standard Pazon. The Pazon starts marginally better, probably due to the more retarded low rpm spark. Other than that, I prefer the pick up connection design.

It doesn't use a lot of current and I could easily fit a much smaller battery, but the big Motobatt one I use is strategically placed to put a bit more weight over the front. This battery will easily run a full weekend.

I like and could recommend the Pazon as both cheap and effective. Playing around with more expensive options would never have any returns for me.

Emotionally, I would like a crank mounted pick up, but I think the real benefits are marginal.
 
SteveA said:
I ran that set up in testing. But it didn't survive, so I used the same box with the short advance curve and a cam pick up. Actually I think it ran well, I had no reason to change things other than general annoyance at Boyer pick up connections and a suspicion that the advance curve might not be ideal. Only after changing did I feel that, in fact, the advance curve wasn't an issue at all. I was setting it on the strobe to fully advanced at 5000 anyway, and starting on rollers.

Then I changed it all for a standard Pazon. The Pazon starts marginally better, probably due to the more retarded low rpm spark. Other than that, I prefer the pick up connection design.

It doesn't use a lot of current and I could easily fit a much smaller battery, but the big Motobatt one I use is strategically placed to put a bit more weight over the front. This battery will easily run a full weekend.

I like and could recommend the Pazon as both cheap and effective. Playing around with more expensive options would never have any returns for me.

Emotionally, I would like a crank mounted pick up, but I think the real benefits are marginal.
Click to expand...
What battery do you use Steve and can you share a pic of it mounted ?

And what coil(s) are you running with the Pazon ?

Regarding the crank mounting, personally, with my old Brit stuff, I’ve never found that a couple of degrees either way of nominal makes any measurable difference on the dyno. So I’m with you in that I struggle to believe in the benefits of crank vs cam mounted.
 
Coil is RGM supplied twin coil, very similar to the Boyer coils.

Battery mounting is hung on the front fairing mount, so right behind the front number plate section of the fairing, but, it's a Rickman, so I don't think that will help Commando people (couldn't immediately find a picture anyway, it doesn't excite me that much).

Battery Is Motobatt MB7U, too big really, other than no messing required. Today, I would choose MB4 as about the smallest 12v they produce.
 
It is the yellow lump right in the nose.
 

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Fast Eddie said:
Who did you get the fairing from Steve ?
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Spike Livingstone at Ragged Edge Racing.

Essentially, it is a Seeley fairing but was in itself a copy of the Apollo fairing that Ken Inwood used to sell in both one and two piece versions. I had bought a one piece from Ken in 1977. I was able to buy one of the last 3 piece ones from him in 2009/2010. (BTW does anyone know if he is still with us?)

Spike already had a top half mould. The mould for the lower was made from my previous open bottomed Apollo/Seeley fairing and a few measurements, and is now a standard product for racers needing a catch tray. It has the bulges for the Rickman Frame because I insisted on them as authentic to the Apollo two piece and essential for Rickman lower engine mount lugs.

I don't think they were included in the one piece version, or if they were, they didn't last long!
 

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This is the Inwood Apollo two piece version in 2015, and the first Ragged Edge version.
 

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I use a Boyer ignition with a double-ended 12 volt coil from a CB750 Honda and the lightest 12 volt lead acid battery - total loss. However in the interests of the project, I have thought about buying a programmable Boyer. Modern bikes use a combination of fuel injection asnd ignition curves to get optimum combustion conditions. There have been claims that the shape of the optimum ignition curve cannot be calculated. However most guys probably cannot develop the algorithm which converts crank angle to distance from top dead centre. The same calculation is involved and the ratio of conrod length to stroke changes the shape of the ignition curve.
I have discovered that the high level computer language which is now most used is Python, so getting the shape of the curve from the calculation would not be difficult.
The other alternative would be to buy an ignition system which has a choice of curves, but that option introduces more variables.
We would need to find a programmable ignition system which works well on a bike with similar rod length to stroke ratio.
 
Nigel, you are an engineer and know about trigonometry. When I was bulding my T250 Suzuki engine. I had use of one of the first minicomputers in Victoria. I created a table which related port heights to degrees of crankshaft rotation. That calculation can be used to derive an optimum ignition curve, if you arbitraily decide the times over which combustion occurs in the motor. If you get it wrong, all you need to do is shift the whole curve while using a dyno
 
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