Joe Hunt magneto

Schwany said:
Not an answer, more a pile of BS

I doubt any battery small enough to make using one worthwhile without a charger in the paddock between sessions would last 240 minutes. If using LiFEPO4 the battery could go completely dead in short order if it got below 10V. A magneto would be by far the safest bet as an all in one ignition system. Obviously, that is why you want to use one.

You are not racing anymore, are you?

I know less weight = more fun, better handling, and a less tiring riding experience when trying to go fast even on the road. Do you think the weight difference of using an alternator will be that significant for what you intend to do? What is the weight delta between running with an alternator and a small LiFEPO4 battery and running with a magneto batteryless and no charging system?

Odd tidbit of info. I have a few of those 12V 1.3amp batteries. They won't even power a timing light for more than a couple of seconds.
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Its not being raced, but is a track use only bike. An alternator is not the done thing. Everyone would laugh at me and I’d be banished to the corner of the paddock with all the other odd balls and freaks.

The Maney cases would need work, belt cover would need to be special, but more importantly they rob BHP and it would be introducing another potential failure mode. Might well cause difficulties with providing way too much power, it’d be at high revs all the time with a very, very, low draw. Def not the done thing.
 
Fast Eddie said:
Its not being raced, but is a track use only bike. An alternator is not the done thing. Everyone would laugh at me and I’d be banished to the corner of the paddock with all the other odd balls and freaks.

The Maney cases would need work, belt cover would need to be special, but more importantly they rob BHP and it would be introducing another potential failure mode. Might well cause difficulties with providing way too much power, it’d be at high revs all the time with a very, very, low draw. Def not the done thing.
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The 1970s CCM moto crossers had a smallish for the day rechargeable battery fitted inside the ignition box. During a meeting It could be recharged from the van 12volt battery if need, from memory it never did.
 
cash said:
The 1970s CCM moto crossers had a smallish for the day rechargeable battery fitted inside the ignition box. During a meeting It could be recharged from the van 12volt battery if need, from memory it never did.
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That was probably Interspan ignitions, my favourite, but Mr Interspan has now become virtually impossible to deal with sadly.
 
NorLuck said:
Lots of talk in October about magnetos, so did you get a JH Magneto or not in the end?
Assuming you mean Commando engine when you say Maney cases, so what did you do to the clutch side if you've deleted the rotor. Pics?
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Nah… didn’t buy one in the end…

I bought two !!

Joe Hunt magneto
 
seattle##gs said:
JH recommends setting their mag at 28 degrees BTDC. Most electronic ignitions use 30 - 32 degrees. Any experience with this difference? I installed a JH mag the other day and it wants to kick back. I timed it to 30 degrees at 2000 rpm. There is a little chatter while timing...the timing mark is not dead still.
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Most electronic ignition that use 30 to 32 degrees of timing don't have an advance curve similar to the original AAU. They have a continuous straight line that is a bit of a compromise.
 
NorLuck said:
Very cool, why did you feel the retard switch was necessary?

And what are you doing with the drive side? Just a spacer to hold the sprocket in place?
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Ease of starting.

Yes, simple spacer in place of the alternator rotor, very ‘standard’ in this kinda application.
 
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NorLuck said:
Send me one of them spacers thanks!

Also you have an electric start in one bike and surely the other bike doesn’t have a kickstart lever so why the switch if it’s treadmill start or estart?
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Even with starting rollers, a big high CR engine will be easier to start retarded. And as there’s no down side, the real question is ‘why not’ ?!
 
NorLuck said:
Just curious. Ash kick starts his drink while seated eating cheetos and making gestures at kangaroos that try to fight him. He doesn’t have a lever. I’m choosing not to have one on mine. Just wondering why you went with one.

Please post an installation guide etc for me ;)

Ash I <3 your many many posts about this very topic. I read them all and enjoy them all, you bring me hope and inspire me (which is why I have one mag sitting in the garage and one hopefully coming in the mail). The above was a tribute paragraph to your awesomeness and on the topic of building a 650 with Jim bits, I’d buy your legendary 850 featherbed if you wanted to sell it to fund a badass 650 project.
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You’ll be fine. Your motor is 850 with stock CR IIRC. A JH mag without retard is proven to work well on that set up.
Save your worry energy for something more worrisome.
 
Even with a high CR engine a JH will fire up easy without retarding it but Jim does the retard switch mod to the JH for starting, but really a stock motor even with high compression and a few other goodies in the motor I have never needed to retard for easy starting always first kick every time, when I brought my JH I got it through Low Brows as it was cheaper than buying direct from JH themselves and at the time Jim wasn't doing the mods to the JH maggies, but having ran the old JH on my old Triumph I knew how good they were and how reliable the JH are and the newer JH are even better with the 4 rare earth magnets with an even bigger bang from the spark, I been zapped by my old JH and wasn't nice, so far haven't been zapped with the new one yet lol.
Norluck my Commando/Featherbed 850 will be with me forever till the day I leave this earth, my youngest daughter will get it then, not sure what she will do with it, she been into bikes from an early age with dirt bikes and now has a Triumph triple, the 650 Dommie project was for her but at the time she got into Japanese drift cars, but now she's back on the right road and bikes again.

Ashley
 
A magneto with retard offers easier starting than most EIs because the spark is hotter at slow kickstart RPM. And mags are repairable where an EI usually isn't. That big lunk hanging off the side looks pretty cool in my opinion - even if it is off a Tractor. And you can get rid of the battery once and for all - no more of that maintenance to worry about. Concerned about kickback - get the retard lever or run it behind the cylinders like I do - 10+ years of reliable service and easy starting. Its a shame that the smaller ARD is no longer available. Some enterprizing opportunist ought to do the right thing and re-introduce it. I guarentee it would sell.



The look is a conversation starter.
Joe Hunt magneto




The out of production ARD that needs to come back into production.
Joe Hunt magneto


The magic retard lever
Joe Hunt magneto


Behind the cylinders where it really belongs - 10+ years of reliable 1st kick starting in 100 deg+ hot climate with neodemium magnets.
Joe Hunt magneto
 
I think a lot of us would like to see the timing side ARD mag back in production. A friend of mine had some discussions with the owner of ARD, who is retired but still has all the design and production stuff for the mags, but I don't think we will see them reintroduced. Too bad.

This is a picture of the last version of the design, which sticks out a good bit less than the one posted above. Ignore the welding on the timing cover. I did it to repair a damaged cover. The mag is normally just a bolt-on item.

Joe Hunt magneto


Ken
 
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To be honest I don't mind my JH hanging out from the timing side of the motor, out in the cool, showing off, but it seems to upset so many on here about its position and really off a tractor well to me they work pretty good for anything and having that big huge spark from low revs to full on revs it just gets bigger the faster they spin, I have never had any problems with kick back once set right and in over 12 years or more I haven't touched it just take the front cover off every service to check the point and a dab of lube on the felt for the point cam, a 2 minute job, if people are concern or worrying about it hanging off the side about getting damage after dropping it or any reason at all then worrying about things like that maybe it's time to never ride a bike again, I don't even think about it or let it worry me at all, but it seems to with so many on here.
Another thing look at the primary side of the motor and see how far it sticks out as well with triplex chain/sprocket, the Rota and alt hanging off the end of the crank, with the JH hanging off the other side might just even things up, well that's how I think of it, as I have always said it don't worry me at all and it's a lot easier to work on there if need too, easier to pull off to work on it on the bench if need to, so far in over 12 years running haven't had the need to pull it off, first kick every time even without retarding it without any kick back at all.
Well it's up to everyone to decide what ignition to run on their Norton, I have used stock set up 3 EL ignitions and to be honest the JH puts out the best and biggest spark of them all, in the 46 years with 2 failed EI and a few failed batteries in that time, I have over 26 years of running JH maggies and have never in that time had any problems with both and with a lot of miles clocked up on my first one and as Jim said they can be repaired/rebuild parts are cheap a complete tune up kits for $35 and the best thing as well long life out of the spark plugs they run so clean and so far I haven't replaced the spark plugs since I been running the JH and every time I pull the plugs I just look at them and put them straight back in, they don't seem to wear and always run clean.
Nigel those 2 JHs look so good and good workmanship and so simple, I think you be very happy with them both as I love my Joe Hunt, best bang for my money and would I go for another one if I need too, hell yeah.

Ashley
 
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NorLuck said:
You don't sell the bit that the Mercury needs to have a Mag behind the timing cover. In fact I'm still not quite sure what part I do need!
This all I need?: https://www.rgmnorton.co.uk/buy/magneto-automatic-advance-retard-assembly_4367.htm
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The AAU in the link above is intended to mount on the drive shaft of a magneto that is flange mounted behind the cylinders as shown in jseng fourth photo down.

The AAU has a 14 degree rotation between the sprocket and the central hub which drives the magneto shaft. This amounts to 28 crankshaft degrees. Centrifugal bob weights with spring return provides the action to rotate the hub relative to the spocket.

If your Mercury originally was fitted with a magneto, then this is all you need to fit a JH mag flange mounted as shown above and have automatic timing advance.

Slick
 
NorLuck said:
Nope, Mercury by definition has ignition instead of magneto. So would need something.. Maybe that part? Maybe a different sized chain? Other things? I'm not sure.
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I'm pretty sure the mercury crankcase is the same as a dommie ?
So if you really want a magneto just fit a Lucas one in place of your dizzy
With an AAU or manual advance
 
baz said:
I'm pretty sure the mercury crankcase is the same as a dommie ?
So if you really want a magneto just fit a Lucas one in place of your dizzy
With an AAU or manual advance
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Yes if it has the normal points unit then you can just swap it out for a mag. Probably easiest to use a manual adbance retard.
 
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If you go for a Joe Hunt behind the cylinders, the retard lever shown earlier doesn’t fit.
Hence you’d need the AAU, or not worry about it (as Ashley hasn’t for 40 odd years)!
 
Fast Eddie said:
If you go for a Joe Hunt behind the cylinders, the retard lever shown earlier doesn’t fit.
Hence you’d need the AAU, or not worry about it (as Ashley hasn’t for 40 odd years)!
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A mate of mine builds some very fast Tritons
He never uses an AAU or manual advance on any of his pre unit motors
 
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