Can electronic ignitions do this?

Do you realise that if you turn a magneto armature backwards, you can hold the lead and not get a shock ? I had an uncle who was like a brother to me. He got me to hold the lead and touch the magneto, while he turned the armature - then he said 'see-no shock !' ) Then he flicked it in the opposite direction.
 
All I can say is the Joe Hunt works for me, does everything I need it too, always starts on first kick every time without failure without retarding it (has never kicked back when tuned/set right), and my hotrod Norton runs so well with that big spark, and all the ones that knock it have never used one, everyone is an expert without knowing and I been there with other ignitions and been stuck with them, they all had their problems and after 25 years of using Joe Hunt magneto's not once have they let me down and they have survived sliding down the road.

Ashley
 
2 things:

1) I haven't seen a single person here "knock" magnetos.. Not a single person.... again, NOT ONE PERSON.

2) I'm curious about them, so I just asked why they don't incorporate an advance mechanism into magnetos because spark timing seemed like a necessary thing on a lot of engines.... (maybe lawn mowers have fixed spark timing...) I think the answers are interesting. As Jim said very early in the thread, some magnetos had an advance mechanism in the sprocket for the magneto, and some had an advance in the magneto, but not all engine configurations suffer a great loss of efficiency without a complete advance curve to match the engine's RPM's. It seems that some engine configurations work well enough without an advance mechanism (parallel twins being one) so in that case a much simpler magneto works just fine. Car engines seem to need an advance mechanism, probably because of the complexity of the ignition for that many more cylinders. (I'm still reading about that and wondering why that is...)

It's not a "shit" or "gold" proposition to ask about the strengths and weaknesses of any mechanism's mechanical properties. Sometimes it's just insatiable curiosity.... 😏
 
"Car engines seem to need an advance mechanism, probably because of the complexity of the ignition for that many more cylinders. (I'm still reading about that and wondering why that is...)"

See post #25
 
o0norton0o said:
2 things:

1) I haven't seen a single person here "knock" magnetos.. Not a single person.... again, NOT ONE PERSON.

2) I'm curious about them, so I just asked why they don't incorporate an advance mechanism into magnetos because spark timing seemed like a necessary thing on a lot of engines.... (maybe lawn mowers have fixed spark timing...) I think the answers are interesting. As Jim said very early in the thread, some magnetos had an advance mechanism in the sprocket for the magneto, and some had an advance in the magneto, but not all engine configurations suffer a great loss of efficiency without a complete advance curve to match the engine's RPM's. It seems that some engine configurations work well enough without an advance mechanism (parallel twins being one) so in that case a much simpler magneto works just fine. Car engines seem to need an advance mechanism, probably because of the complexity of the ignition for that many more cylinders. (I'm still reading about that and wondering why that is...)

It's not a "shit" or "gold" proposition to ask about the strengths and weaknesses of any mechanism's mechanical properties. Sometimes it's just insatiable curiosity.... 😏
Click to expand...

I think you’ve summarised it there.

There’s no doubt that a proper advance and retard is better in theory, and most modern (read efficient) engines do vary the timing for a multitude of reasons.

But on these old (read inefficient) lumps, they’re about as fussy as the lawn mower you mentioned about such things!
 
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I would never have another magneto on a race bike. A Boyer with a battery does the job much better. Getting to a race meeting and have a miss in the motor due to the capacitor inside the armature of a magneto REALLY PISSES ME OFF. The last time it happened to me, I was 200 Km from home and had paid all the entry and licence fees to race.
In Australia, we have magic people who fix magnetos - one is somewhere up north, and he is a dud.
I replaced the Lucas Wader for a 4 cylinder Lucas SR, and ran two leads to each plug. The capacitor was external. But the whole thing looked like a piece of shit. What does a Joe Hunt magneto make a Commando look like ? An historic motorcycle should probably look right for the era which it pretends to represent.
My mate who originally built my Seeley 850 as a Laverda gets upset when I call it a 'shit-heap'. But that is what it is. This year's Goodwood Revival is up on Youtube. Have a look at the real deal.

2024 goodwood revival barry sheene - Search Videos

www.bing.com www.bing.com
 
One of my mates said to me 'at least your bike looks right'. He does not realise it is almost impossible to build it differently and still get it to function. If one of those old guys who used to do concours' inspections ever saw it, they would have apoplexy. I built it as a race bike - not something else. Historic racing is bullshit - it destroys good classic bikes.
Ashley's bike is a road bike, nobody is going to go to a race meeting to see it.
 
The newer Joe Hunts will out preform the old Lucas magneto's and they are more compacted as well the point, condenser and coil is just under the front cover, all easy to get to and if I was using one to race the preparation is very important and a tune up kit be wise to have, comes with point, condenser and new plug leads, if you go racing then it's always wise to carry important spares, $45 for a tune up kit I have 2 spare kits in my part cabinet but in 13+ years haven't needed to replace yet and 2 spare front covers just incase.
The JH behind the cylinder are well hidden but I like mine hanging in the breeze where is runs nice and cool.
So Al if you don't prepare for race meet and take parts that maybe needed you only have yourself to blame if something simple stops you getting started.

Ashley
 
The advance mechanism is (was) all about starting. It should actually be called an automatic retard because that is its actual purpose. Originally, vehicles had a manual lever to retard the ignition for starting, then you would move the lever to the run ("advanced") position after it was running. The centrifugal advance mechanism did away with the need for a manual lever and provided exactly the same function. Most engines will start just fine at full advance with an electric starter...kick starting (or cranking an old car) is a different issue...though apparently these JH magnetos can do that. I thought they had an advance mechanism in them but based on what I'm reading here, they don't. Not sure how they can start at kick-start speed without kickback but apparently they can!
 
I suspect I could get a bit more go with a programmable advance curve, but a lot depends on the fuel. Methanol is much more foregiving than petrol.
Steve Oszko had a green frame Ducati Super Sport 750. He fitted a crank triggered ignition system from a Honda VT 750. He said it was 'less harsh'. It took a lot of work on the trigger to get it to advance properly. He was a motor mechanic and had the tuning electronics.
It might be more difficult to fit one to a Commando.
 
I've always taken a lawn mower or rototiller mechanical approach to the Norton engine. Too heavy to power a handheld weed whacker.
 
I have kick-started a 1000cc Vincent which was on 13 to 1 compression. You just don't go at it like a bull at a gate. Just push a piston well up a bore, and give it a solid confident shove. The only time I ever got really caught was when there was a flake of bone broken-off inside my knee. I tried to kick start a 60s Bonneville which had race cams. It immediately bit me, and I ended-up on the ground in agony. So I had the knee op and learned to walk again.
 
acotrel said:
I have kick-started a 1000cc Vincent which was on 13 to 1 compression. You just don't go at it like a bull at a gate. Just push a piston well up a bore, and give it a solid confident shove. The only time I ever got really caught was when there was a flake of bone broken-off inside my knee. I tried to kick start a 60s Bonneville which had race cams. It immediately bit me, and I ended-up on the ground in agony. So I had the knee op and learned to walk again.
Click to expand...
Bingo.

And that’s why modern EI’s like Tri Spark have anti kickback functions… and why it’s well worth having.

ESPECIALLY with the age demographic involved !
 
ashman said:
The newer Joe Hunts will out preform the old Lucas magneto's and they are more compacted as well the point, condenser and coil is just under the front cover, all easy to get to and if I was using one to race the preparation is very important and a tune up kit be wise to have, comes with point, condenser and new plug leads, if you go racing then it's always wise to carry important spares, $45 for a tune up kit I have 2 spare kits in my part cabinet but in 13+ years haven't needed to replace yet and 2 spare front covers just incase.
The JH behind the cylinder are well hidden but I like mine hanging in the breeze where is runs nice and cool.
So Al if you don't prepare for race meet and take parts that maybe needed you only have yourself to blame if something simple stops you getting started.

Ashley
Click to expand...
A complete spare motorcycle ? I once dropped a 650 Triumph on a greasy road, and the BTH magneto stopped working. While they are working magnetos are great. The rotating magnet ones are pretty good. The Lucas SR are similar to the racing magnetos which were used on the Manx, and they are cheap. But a Commando engine does not have the other chain and the mount like a Dominator, otherwise I would be using one.
 
My friend's son took the 350cc Manx from Melbourne to Goulburn to race. Then did not know how to get rid of the miss in the motor when he was accelerating in practice. It wasn't the magneto - have to wonder about some people. I would have thought that was the most basic possible issue. I think he is also a trained motor mechanic.
 
I've asked before, where's the Urban Legends forum? Over 100 posts here worth two at least threads there :)
 
I have asked this question before but not here, everyone keeps talking about retarding and kickback and yet my Joe Hunt set up off the side of my timing case direct drive off the end of the cam myself and my mates who run the same set up off their old Triumphs never have any problems with KB or starting at full advance, but Jim has always done the Joe Hunt set up behind the cylinders where the old Lucas magneto's run using the advance/retard system as well the extra drive chain added to the cam chain, so if running the extra drive chain for the magneto has a effect on the starting to need to retard the magneto for ease of starting where running off the end of the cam I have no problems with kickback or starting the motor on first kick with full advance.
Does anyone else run a JH off the side of their Norton or Triumph who also don't have a problem with starting or kickback or am I just the only one as well as my mates who still run with a JH off the side and mates who had run them off the side without any starting problems at all or KB.
A simple question as everyone else seems to need to retard the timing of the JH to prevent kick back or eses of starting, 24 years experience with running 2 Joe Hunts off the side and I don't get any kick back and always fires on first kick without retarding.
Even with out of tune carbs the Norton still fires up easy with the JH magneto.
I just like to know why so many need to retard to start or worry about KB when myself and mates don't have any problems at all and I am talking about Joe Hunt magneto's here the 4 rare earth and the older 2 rare earth JHs.
Also condenser seem to have problems but I haven't had any problems with my condensers or points for that matter.

Ashley
 
ashman said:
I have asked this question before but not here, everyone keeps talking about retarding and kickback and yet my Joe Hunt set up off the side of my timing case direct drive off the end of the cam myself and my mates who run the same set up off their old Triumphs never have any problems with KB or starting at full advance, but Jim has always done the Joe Hunt set up behind the cylinders where the old Lucas magneto's run using the advance/retard system as well the extra drive chain added to the cam chain, so if running the extra drive chain for the magneto has a effect on the starting to need to retard the magneto for ease of starting where running off the end of the cam I have no problems with kickback or starting the motor on first kick with full advance.
Does anyone else run a JH off the side of their Norton or Triumph who also don't have a problem with starting or kickback or am I just the only one as well as my mates who still run with a JH off the side and mates who had run them off the side without any starting problems at all or KB.
A simple question as everyone else seems to need to retard the timing of the JH to prevent kick back or eses of starting, 24 years experience with running 2 Joe Hunts off the side and I don't get any kick back and always fires on first kick without retarding.
Even with out of tune carbs the Norton still fires up easy with the JH magneto.
I just like to know why so many need to retard to start or worry about KB when myself and mates don't have any problems at all and I am talking about Joe Hunt magneto's here the 4 rare earth and the older 2 rare earth JHs.
Also condenser seem to have problems but I haven't had any problems with my condensers or points for that matter.

Ashley
Click to expand...
To me, it's very simple. If the engine is spinning fast enough when the spark happens to carry through TDC, then there is no kickback. If not spinning fast enough, then there is no convincing me that it won't kick back. The only way to stop kickback with the engine spinning too slow is to not spark - maybe the magneto simply does not spark when too slow?

Also, identical plugs with identical gaps in the same engine need exactly the same voltage to spark and once the gap breakdown voltage is achieved, the exact same current will flow. So, a magneto, no matter who makes it, will not provide more spark energy than points and coils with everything else being the same. At higher RPMs, larger plugs gaps, higher compression, and/or more fuel/air in the cylinder, then a Lucas (or other) coil can run out of potential voltage and a magneto increases potential voltage at higher speeds so the magneto can be better in those conditions. And, of course, the magneto system has less components so is likely to be more reliable (not reliable, more reliable).

A shorted condenser will stop your magneto from producing spark. An open condenser will soon cause points failure - no matter coil/points or magneto ignition. Points with the "mountain" on one side and "valley" on the other (caused by too much arcing) will cause no spark no matter the coil/points or magneto ignition. The wrong value condenser will cause too much arching at certain RPMs and again will cause no spark. If you have points that never need cleaning/filing then you have perfect condensers for all RPMs that never fail (not buying that, condensers are only perfect at a very small RPM range).
 
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